Microscopic Examination of Urine | from Strasinger (6th ed.) Flashcards
1
Q
What is the 3rd part of routine UA (after physical and chemical examination)?
A
Microscopic examination (of urinary sediment)
2
Q
What is the purpose of microscopic examination of the urinary sediment?
A
To detect and to identify insoluble materials present in the urine
3
Q
What contributes formed elements to the urine?
A
1) Blood
2) Kidney
3) Lower genitourinary tract
4) External contamination
4
Q
What are the formed elements (w/c are contributed by blood, kidney, lower GUT, and external contamination) in the urine?
A
1) RBCs
2) WBCs
3) Epithelial cells
4) Casts
5) Bacteria
6) Yeast
7) Parasites
8) Mucus
9) Spermatozoa
10) Crystals
11) Artifacts
5
Q
True or False
All of the formed elements in the urine are clinically significant and others are considered abnormal
A
False, because some of the formed elements in the urine are of no clinical significance and others are considered normal
6
Q
Some of the formed elements are of no clinical significance and others are considered normal unless what?
A
Unless they are present in increased amts
7
Q
What must be included in the examination of the urinary sediment?
A
It must include both identification and quantitation of the elements present
8
Q
Microscopic analysis is subject to several procedural variations including what methods?
A
Including the methods by w/c:
1) The sediment is prepared
2) The volume of sediment actually examined
3) The methods used to obtain visualization
4) The equipment used to obtain visualization
5) The manner in w/c the results are reported
9
Q
True or False
Protocols have been developed to increase the standardization and cost-effectiveness of microscopic UA
A
True
10
Q
What is done by many labs to enhance the cost-effectiveness of UA?
A
Many labs have developed protocols
11
Q
What are the protocols developed by many labs (to enhance the cost-effectiveness of UA)?
A
Microscopic examination of the urine sediment is performed only on sxs meeting specified criteria
12
Q
True or False
Abnormalities in the physical and chemical portions of the UA play a primary role in the decision to perform a microscopic analysis, thus the use of the term “macroscopic screening”
A
True
13
Q
What are the parameters that are considered significant (w/c vary among labs)?
A
It usually include:
1) Color
2) Clarity
3) Blood
4) Protein
5) Nitrite
6) LE
7) Glucose (possibly)
14
Q
True or False
Lab-designed criteria can also be programmed into automated instruments
A
True
15
Q
True or False
Percentages of abnormal sxs that would go undetected using parameters differ significantly among studies
A
True
16
Q
True or False
It is okay to not consider pt population when developing protocols for macroscopic screening
A
False, because pt population must also be considered when developing protocols for macroscopic screening
17
Q
Who are the individuals / population that must also be considered when developing protocols for macroscopic screening?
A
1) Pregnant women
2) Pediatric
3) Geriatric
4) Diabetic
5) Immunocompromised
6) Renal pts
18
Q
What is the meaning of CLSI?
A
Clinical and Laboratory Standards Institute
19
Q
What does CLSI recommend w/ regards to when should microscopic examination be performed?
A
It recommends that microscopic examination be performed when:
1) Requested by a physician
2) A lab specified pt population is being tested
3) Any abnormal physical or chemical result is obtained
20
Q
When should sxs be examined?
A
Sxs should be examined while:
1) Fresh
2) Or adequately preserved
21
Q
What are the primary formed elements that disintegrate rapidly (particularly in dilute alkaline urine)?
A
1) RBCs
2) WBCs
3) Hyaline casts
22
Q
Refrigeration of sxs may cause what?
A
It may cause precipitation of:
1) Amorphous urates
2) Amorphous phosphates
3) Other nonpathologic crystals
23
Q
What is the action of amorphous urates and phosphates and other nonpathologic crystals (w/c are present when the sx is refrigerated)?
A
These can obscure other elements in the urine sediment
24
Q
What may be the action of warming the sx to 37 DC (prior to centrifuging)?
A
It may dissolve some of the crystals (other nonpathologic crystals)
25
What is the method of urine collection that minimizes external contamination of the sediment?
Midstream clean-catch
26
As w/ physical and chemical analyses, what type of sx can cause false-(-) readings?
Dilute random sxs
27
What must be done prior to decanting a portion (of sx) into the centrifuge tube?
Care must be taken to thoroughly mix the sx
28
What is the usual std amt of urine (this is also the volume of urine w/c is centrifuged in a conical tube)?
Between 10 and 15 mL
29
What is the aid of using 10 - 15 mL of urine (and centrifuging it)?
It provides an adequate volume from w/c to obtain a representative sx of the elements present in the sx
30
What is the volume of urine that is frequently used?
12 mL
31
What are the reasons for why is 12 mL volume of urine frequently used?
1) Because multiparameter rgnt strips are easily immersed in this volume
2) Because capped centrifuge tubes are often calibrated to this volume
32
When is obtaining a 12 mL sx not possible?
For pediatric pts
33
What should be done if obtaining 12 mL sx is not possible?
The volume of sx used should be noted on the report form
34
What is the aid of noting the volume used (specifically if obtaining 12 mL sx is not possible) in the report form?
This allows the physician to correct the results
35
What is done by some labs when obtaining 12 mL urine is not possible?
Some labs choose to make the correction prior to reporting
36
Provide an ex of the application of correction being done (if obtaining 12 mL urine is not possible)
If 6 mL of urine is centrifuged, the results are multiplied by 2
37
True or False
It is okay even if the speed of the centrifuge and length of time the sx is centrifuged are not consistent
False, because the speed of the centrifuge and length of time the sx is centrifuged should be consistent
38
What is the meaning of RCF?
Relative centrifugal force
39
What is the meaning of RPM?
Revolutions per minute
40
What is the action of centrifugation for 5 mins at a RCF of 400?
It produces an optimum amt of sediment w/ the least chance of damaging the elements
41
What should be used to correct for differences in the diameter of centrifuge heads?
RCF rather than RPM should be used
42
Where is the RPM value shown?
On the centrifuge tachometer
43
What should be used to convert RPM value to RCF?
Use nomograms (w/c are available in many lab manuals) or by using the formula:
RCF = 1.118 x 10^-5 x radius in centimeters x PRM^2
44
True or False
It is okay to not routinely perform centrifuge calibration
False, because centrifuge calibration should be routinely performed
45
What can be used to slow the centrifuge?
Braking mechanism
46
The use of braking mechanism to slow the centrifuge causes what?
It causes disruption of the sediment prior to decantation
47
Based on the effect caused by the braking mechanism to slow the centrifuge, should braking mechanism be used / done?
No
48
What should be done to prevent biohazard aerosols?
All sxs must be centrifuged in capped tubes
49
What is/are the significance of the given screening test (in macroscopic screening and microscopic correlations)?
Given screening test: Color
Blood
50
What is/are the significance of the given screening test (in macroscopic screening and microscopic correlations)?
Given screening test: Clarity
1) Hematuria vs. hgburia / myoglobinuria
| 2) Confirm pathologic or nonpathologic cause of turbidity
51
What is/are the significance of the given screening test (in macroscopic screening and microscopic correlations)?
Given screening test: Blood
1) RBCs
| 2) RBC casts
52
What is/are the significance of the given screening test (in macroscopic screening and microscopic correlations)?
Given screening test: Protein
1) Casts
| 2) Cells
53
What is/are the significance of the given screening test (in macroscopic screening and microscopic correlations)?
Given screening test: Nitrite
1) Bacteria
| 2) WBCs
54
What is/are the significance of the given screening test (in macroscopic screening and microscopic correlations)?
Given screening test: LE
1) WBCs
2) WBC casts
3) Bacteria
55
What is/are the significance of the given screening test (in macroscopic screening and microscopic correlations)?
Given screening test: Glucose
Yeast
56
What should remain in the tube after decantation?
Uniform amt of:
1) Urine
2) Sediment
57
What are the volumes that are frequently used (in terms of sediment preparation)?
1) 0.5 mL
| 2) 1.0 mL
58
What is the computation for sediment preparation?
Volume of urine centrifuged divided by the sediment volume = conc. factor
59
What is the conc. factor (via the use of computation) if the volume of the sediment is 0.5 mL?
24
60
What is the conc. factor (via the use of computation) if the volume of the sediment is 1.0 mL?
12
61
The sediment conc. factor relates to what?
To the probability of detecting elements present in low quantities
62
When is sediment conc. factor used?
It is used when quantitating the # of elements present per milliliter
63
What should be done (in terms of sediment preparation) to maintain a uniform sediment conc. factor?
The urine should be aspirated off rather than poured off
Aspiration > pouring
64
When can pouring of urine (in terms of sediment preparation) be done instead of aspiration?
If specified by the commercial system in use
65
True or False
All systems provide pipettes for the purpose of aspirating urine (rather than pouring it off | in terms of sediment preparation)
False, because some systems provide pipettes for the purpose of aspirating urine (rather than pouring it off | in terms of sediment preparation)
66
What are the other uses of pipettes (w/c are provided by some systems for aspirating urine | in terms of sediment preparation)?
1) These are also used for sediment resuspension
| 2) Also, these are used for transferring sxs to the slide
67
What must be done to the sediment (when it is already prepared)?
It must be thoroughly resuspended
68
How to thoroughly resuspend the sediment (after preparation)?
Via gentle agitation
69
What are the ways on how to thoroughly resuspend the sediment (after preparation)?
1) Via the use of a commercial-system pipette
| 2) Or by repeatedly tapping the tip of the tube (via the use of finger)
70
Can vigorous agitation be done to thoroughly resuspend the sediment (after preparation)?
No, it should be avoided
71
Why should vigorous agitation be avoided when thoroughly resuspending the sediment?
Because it may disrupt some cellular elements
72
Why is thorough suspension (of the sediment) essential?
To provide equal distribution of elements in the microscopic examination fields
73
True or False
It is okay to not be consistent on the volume of sediment (for each sx) placed on the microscope slide
False, because the volume of sediment placed on the microscope slide should be consistent for each sx
74
When using the conventional glass-slide method, what is the recommended volume of sx (/ sediment) and what should be done to this volume of sediment?
20 uL (0.02 mL) w/c should be covered by a 22 x 22 mm glass cover slip
75
What may be the result of allowing the sx (/ sediment) to flow outside of the coverslip (if the conventional glass-slide method is used)?
It may result in loss of heavier elements (such as casts)
76
What is the difference between the application of conventional glass-slide method and commercial systems (when it comes to the volume of the sediment to be examined)?
Commercial systems control the volume of sediment examined
77
How do commercial systems control the volume of sediment examined?
By providing slides w/ chambers w/c are capable of containing a specified volume
78
What should be done when commercial systems are used (in terms of the volume of sediment examined)?
Care must be taken to ensure the chambers are completely filled
79
What are the info that the product literature supply?
1) Chamber volume
2) Size of the viewing area
3) Approx # of low-power viewing areas
4) Approx # of high-power viewing areas
This are all based on the area of the field of view using a std microscope
80
The information (supplied by the product literature) together w/ the sediment conc. factor are necessary to what?
To quantitate cellular elements per milliliter of urine
81
What is the conventional method of examining the urine sediments?
1) Place a drop of centrifuged urine on a glass slide
2) Add a cover slip
3) Examine the sediment microscopically
82
The conventional method of examining the urine sediments has been substantially improved through what?
Through the use of commercial slide systems
83
What does the CLSI recommend (in terms of examination of urine sediments)?
It recommends the use of commercial slide systems together w/ the standardization of all phases of the methodology, including the conventional method
84
What are the systems that are currently available (in connection w/ examination of urine sediments)?
1) KOVA
2) Urisystem
3) Count-10
4) Quick-Prep Urinalysis System
5) CenSlide 2000 Urinalysis System
6) R/S Workstations 1000, 2000, 2003
85
What are the variety of options that are provided by systems (in terms of examination of urine sediments)?
1) Capped, calibrated centrifuge tubes
2) Decanting pipettes to control sediment volume
3) Slides that control the amt of sediment examined
4) Produce a consistent monolayer of sediment for examination
5) Provide calibrated grids for more consistent quantitation
86
The Cen-Slide and R/S Workstations do not require what?
It do not require manual loading of the centrifuged sx onto a slide and are considered closed systems that minimize exposure to the sx
87
Cen-Slide provides a what?
It provides a specially designed tube that permits direct reading of the urine sediment
88
The R/S Workstations consist of what?
It consist of a glass flow cell into w/c urine sediment is pumped, microscopically examined, and then flushed from the system
89
Microscopic examination (of the sediment) should be performed in what manner?
It should be performed in a consistent manner
90
What is the minimum # of fields (both low and high power) that should be observed when examining the sediment?
10
91
What is the magnification in low power field?
10x
92
What is the magnification in high power field?
40x
93
What is the method of examining the sediment?
1) The slide is 1st examined under low power
| 2) When elements (such as casts) that require identification are encountered, the setting is changed to high power
94
What are the reasons for why is the slide 1st examined under low power?
1) To detect casts
| 2) To ascertain the general composition of the sediment
95
What is the characteristic of casts (when conventional glass-slide method is used | during examination of sediment)?
They have a tendency to locate near the edges of the cover slip
96
Due to the characteristic of casts (when conventional glass-slide method is used | during examination of sediment), what is recommended to be done?
Low-power scanning of the cover-perimeter is recommended
97
Does the characteristic of casts (when conventional glass-slide method is used | during examination of sediment) occur when using standardized commercial systems?
No
98
What is the characteristic of many sediment constituents when the sediment is examined unstained?
They have a refractive index similar to urine
99
Due to the characteristic of many sediment constituents (when the sediment is examined unstained), what is essential to be done?
It is essential to examine sediments under reduced light when using bright-field microscopy
100
True or False
Initial focusing can be difficult w/ a fluid sx
True
101
True or False
Care must be taken to ensure that the examination is being performed in the correct plane
True
102
What is the urinary sediment that will often be present to provide a point of reference?
Epithelial cell
103
True or False
Focusing on artifacts should be avoided
True
104
What are the reasons why should focusing on artifacts be avoided?
1) Because they are often larger than the regular sediment elements
2) Because it can cause the microscopist to examine objects in the wrong plane
105
Continuous focusing w/ the fine adjustment aids in what?
It aids in obtaining a complete representation of the sediment constituents
106
True or False
The terminology and methods of reporting may differ slightly among labs but must be consistent within a particular lab system
True
107
How are casts routinely reported?
These are reported as the average # per low-power field (lpf) following examination of 10 fields
108
How are RBCs and WBCs routinely reported?
These are reported as the average # per 10 high-power fields (hpf)
109
What is the manner of frequent reporting of epithelial cells, crystals, and other elements?
Semiquantitatively
110
How are epithelial cells, crystals, and other elements frequently reported (semiquantitatively)?
1) Rare
2) Few
3) Moderate
4) Many
This should follow lab format as to lpf or hpf use
111
How is the other manner of reporting epithelial cells, crystals, and other elements reported?
1) 1+
2) 2+
3) 3+
4) 4+
This should follow lab format as to lpf or hpf use
112
What must labs also do in terms of reporting epithelial cells, crystals, and other elements?
Labs must also determine their particular reference values based on the sediment conc. factor in use
113
Provide an ex of where labs determine the particular reference values of sediments based on the sediment conc.
For Urisystem, w/ a conc. factor of 30, states a reference value for WBCs of 0 - 8/hpf as opposed to the conventional value of 0 - 5/hpf used w/ a conc. factor of 12
114
Converting the ave # of elements per lpf or hpf to the # per milliliter provides what?
It provides standardization among the various techniques in use
115
What are the steps for converting the ave # of elements per lpf or hpf to the # per milliliter?
1) Calculating the area of an lpf / hpf for the microscope in use using the manufacturer-supplied field of view diameter and the formula: πr^2 = area
2) Calculating the maximum # of lpfs or hpfs in the viewing area
3) Calculating the # of hpfs per milliliter of urine tested using the conc. factor and the volume of sediment examined
4) Calculating the # of formed elements per milliliter of urine by multiplying the # of hpfs per milliliter by the ave # of formed elements per field
116
True or False
In converting the ave # of elements per lpf or hpf to the # per milliliter, provided the same microscope and volume of sediment examined are used, the number of lpfs and hpfs per mL of urine remains the same, thereby simplifying the calculation
True
117
True or False
Labs should evaluate the advantages and disadvantages of adding an additional calculation step to the microscopic examination
True
118
What does CLSI state in terms of reporting (in microscopic examination)?
It states that all decisions w/ regard to reporting of the microscopic should be based on the needs of the individual lab
119
True or False
Procedures (in terms of reporting [in microscopic examination]) should be completely documented and followed by all personnel
True
120
What should be done to the microscopic results?
These should be correlated w/ the physical and chemical findings
121
What is the aid of correlating microscopic results w/ the physical and chemical findings?
To ensure the accuracy of the report
122
What should be done to sxs if the microscopic results does not correlate w/ the physical and chemical findings?
The sxs must be rechecked for both technical and clerical errors
123
True or False
The amt of formed elements or chemicals must also be considered, as must the possibility of interference w/ chemical tests and the age of the sx (in terms of correlating microscopic results)
True
124
Answer the ff questions w/ regards to the given microscopic element:
1) What is/are the correlation/s for physical findings?
2) What is/are the correlation/s for chemical findings?
3) What is/are the exception/s?
Given microscopic element: RBCs
1) Turbidity
1. 1) Red color
2) + Blood
2. 1) + Protein
3) Number
3. 1) Hemolysis
125
Answer the ff questions w/ regards to the given microscopic element:
1) What is/are the correlation/s for physical findings?
2) What is/are the correlation/s for chemical findings?
3) What is/are the exception/s?
Given microscopic element: WBCs
1) Turbidity
2) + Protein
2.1) + Nitrite
2.2) + LE
3) Number
3,1) Lysis
126
Answer the ff questions w/ regards to the given microscopic element:
1) What is/are the correlation/s for physical findings?
2) What is/are the correlation/s for chemical findings?
3) What is/are the exception/s?
Given microscopic element: Epithelial cells
1) Turbidity
| 3) Number
127
Answer the ff questions w/ regards to the given microscopic element:
1) What is/are the correlation/s for physical findings?
2) What is/are the correlation/s for chemical findings?
3) What is/are the exception/s?
Given microscopic element: Casts
2) + Protein
| 3) Number
128
Answer the ff questions w/ regards to the given microscopic element:
1) What is/are the correlation/s for physical findings?
2) What is/are the correlation/s for chemical findings?
3) What is/are the exception/s?
Given microscopic element: Bacteria
```
1) Turbidity
2 Increased / high pH
2.1) + Nitrite
2.2) + Leukocytes
3) Number and type
```
129
Answer the ff questions w/ regards to the given microscopic element:
1) What is/are the correlation/s for physical findings?
2) What is/are the correlation/s for chemical findings?
3) What is/are the exception/s?
Given microscopic element: Crystals
1) Turbidity
1. 1) Color
2) pH
2. 1) Bilirubin
3) Number and type
130
True or False
Many factors can influence the appearance of the urinary sediment
True
131
What are the factors that can influence the appearance of the urinary sediment?
1) Cells (in various stages of development and degeneration)
2) Casts (in various stages of development and degeneration)
3) Distortion of cells and crystals by the chemical content of the sx
4) Presence of inclusions in cells and casts
5) Contamination by artifacts
132
True or False
Since many factors can influence the appearance of the urinary sediment, identification can sometimes be difficult even for experienced lab personnel
True
133
How to enhance identification?
It can be enhanced through the use of:
1) Sediment stains
2) Different types of microscopy
134
What is the actions / purposes of staining?
1) It increases the overall visibility of sediment elements being examined using bright-field microscopy by changing their refractive index
2) It also imparts identifying characteristics to cellular structures such as:
a. Nuclei
b. Cytoplasm
c. Inclusions
135
Do hyaline casts have a refractive index very similar to that of urine?
Yes
136
What is the most frequently used stain in UA?
Sternheimer-Malbin stain
137
What are the components that comprise Sternheimer-Malbin stain?
1) Crystal violet
| 2) Safranin O
138
True or False
Sternheimer-Malbin stain is available commercially under a variety of names
True
139
Sternheimer-Malbin stain are under what names (since it is available commercially)?
1) Sedi-Stain
| 2) KOVA stain
140
What does commercial brands contain?
Stabilizing chemicals
141
What is the action of stabilizing chemicals (w/c are contained in commercial brands)?
These prevent the precipitation that occurred w/ the original stain
142
What are the sediments that absorb the dye (/ Sternheimer-Malbin stain) well?
1) WBCs
2) Epithelial cells
3) Casts
143
What is the effect of Sternheimer-Malbin stain to WBCs, epithelial cells, and casts?
A clearer delineation of structure and contrasting colors of the nucleus and cytoplasm are provided
144
What is 0.5% solution of toluidine blue?
It is a metachromatic stain
145
What is the action of 0.5% solution of toluidine blue?
It provides enhancement of nuclear detail
146
What are the uses of 0.5% solution of toluidine blue?
1) It can be useful in the differentiation between WBCs and renal tubular epithelial cells
2) It is also used in the examination of cells from other body fluids
147
What is the action of 2% acetic acid to the sediment?
It enhances the nuclear detail
148
Can addition of 2% acetic acid (to enhance the nuclear detail) be done for initial sediment analysis? Why or why not?
No, because RBCs are lysed by the acetic acid
149
The passage of lipids across the glomerular membrane results in what?
It results in the appearance of free fat droplets and lipid-containing cells and casts in the urinary sediment
150
What are the lipids that can pass across the glomerular membrane?
1) Triglycerides
2) Neutral fats
3) Cholesterol
151
What are the exs of lipid stains?
1) Oil Red O
| 2) Sudan III
152
What can be used to confirm the presence of lipids (such as TAG, neutral fats, and chole)?
1) Oil Red O
2) Sudan III
3) Polarizing microscopy
153
What is the action of TAG and neutral fats in the presence of lipid stains?
They stain orange-red
154
What is the action of chole in the presence of lipid stains?
It does not stain (but it is capable of polarization)
155
What are the characteristics of TAG, neutral fats, and chole?
1) They can pass across the glomerular membrane
| 2) They are usually present concurrently in the sediment
156
Since TAG, neutral fats, and chole are usually present concurrently in the sediment, what are permitted to be used for their confirmation?
The use of either staining or polarization for their confirmation is permitted
157
Where is Gram stain primarily used?
In the microbiology section (for the differentiation between gram-[+] and gram-[-] bacteria)
158
What is the color of gram-(+) bacteria (via the use of Gram stain)?
Blue
159
What is the color of gram-(-) bacteria (via the use of Gram stain)?
Red
160
What is the role of Gram stain in routine UA?
Its role is limited to the identification of bacterial casts
161
What is the problem in terms of the identification of bacterial casts?
Bacterial casts can easily be confused w/ granular casts
162
What must be used when performing Gram stain?
A dried, heat-fixed preparation of the urine sediment
163
Polynuclear WBCs seen in the urinary sediment are almost always what type of WBC?
Neutrophils
164
What is the characteristic of neutrophils (as seen in the urinary sediment)?
These are associated w/ microbial infection
165
What type of WBCs are present in the sediment in cases of a drug-induced allergic rxn producing inflammation of the renal interstitium?
Eosinophils
166
What is the preferred stain for urinary eosinophils?
Hansel stain
167
What are the components comprised in Hansel stain?
1) Methylene blue
| 2) Eosin Y
168
What is the other stain that can also be used for urinary eosinophils?
Wright's stain
169
Where is staining performed?
On a:
1) Dried smear (of the centrifuged sx)
2) Or cytocentrifuged preparation (of the sediment)
170
What may be seen after episodes of hgburia?
Yellow-brown granules
171
Where may yellow-brown granules be seen (after episodes of hgburia)?
1) In renal tubular epithelial cells
2) In casts
3) Free-floating (in the urine sediment)
172
What is the term called to the yellow-brown granules w/c may be seen in renal tubular epithelial cells, casts, or free-floating in the urine sediment (w/c may be present after episodes of hgburia)?
Hemosiderin
173
What is the stain used to confirm that the yellow-brown granules (w/c may be present after episodes of hgburia) are hemosiderin?
Prussian blue stain (for iron)
174
What is the action of Prussian blue stain (for iron) if hemosiderin granules are present?
It stains the hemosiderin granules a blue color
175
Answer the ff questions w/ regards to the given stain:
1) What is/are the action/s?
2) What is/are the fxn/s?
Given stain: Sternheimer-Malbin
1) Delineates structure; contrasting colors of the nucleus and cytoplasm
2) Identifies WBCs, epithelial cells, and casts
176
Answer the ff questions w/ regards to the given stain:
1) What is/are the action/s?
2) What is/are the fxn/s?
Given stain: Toluidine blue
1) Enhances nuclear detail
| 2) Differentiates WBCs and renal tubular epithelial (RTE) cells
177
Answer the ff questions w/ regards to the given stain:
1) What is/are the action/s?
2) What is/are the fxn/s?
Given stain: 2% acetic acid
1) Lyses RBCs; enhances nuclei of WBCs
| 2) Distinguishes RBCs from WBCs, yeast, oil droplets, and crystals
178
Answer the ff questions w/ regards to the given stain:
1) What is/are the action/s?
2) What is/are the fxn/s?
Given stain: Lipid stains (Oil Red O and Sudan III)
1) Stain TAG and neutral fats orange-red; do not stain chole
2) Identify free fat droplets and lipid-containing cells and casts
179
Answer the ff questions w/ regards to the given stain:
1) What is/are the action/s?
2) What is/are the fxn/s?
Given stain: Gram stain
1) Differentiates gram-(+) and gram-(-) bacteria
| 2) Identifies bacterial casts
180
Answer the ff questions w/ regards to the given stain:
1) What is/are the action/s?
2) What is/are the fxn/s?
Given stain: Hansel stain
1) Methylene blue and eosin Y contains eosinophilic granules
| 2) Identifies urinary eosinophils
181
Answer the ff questions w/ regards to the given stain:
1) What is/are the action/s?
2) What is/are the fxn/s?
Given stain: Prussian blue stain
1) Stains structures containing iron
| 2) Identifies yellow-brown granules of hemosiderin in cells and casts
182
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: RBCs
1) Neutral - pink to purple; acid - pink (unstained); alkaline - purple
183
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the nuclei of stained elements?
2) What is/are the usual distinguishing color/s of the cytoplasm of stained elements?
3) What is/are the comment/s?
Given element in urinary sediment: WBCs (dark-staining cells)
1) Purple
| 2) Purple granules
184
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the nuclei of stained elements?
2) What is/are the usual distinguishing color/s of the cytoplasm of stained elements?
3) What is/are the comment/s?
Given element in urinary sediment: Glitter cells (Sternheimer-Malbin positive cells)
1) Colorless / light blue
2) Pale blue / gray
3) Some glitter cells exhibit brownian movement
185
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the nuclei of stained elements?
2) What is/are the usual distinguishing color/s of the cytoplasm of stained elements?
3) What is/are the comment/s?
Given element in urinary sediment: RTE cells
1) Dark shade of blue-purple
| 2) Light shade of blue-purple
186
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the nuclei of stained elements?
2) What is/are the usual distinguishing color/s of the cytoplasm of stained elements?
3) What is/are the comment/s?
Given element in urinary sediment: Bladder tubular epithelial cells
1) Blue-purple
| 2) Light purple
187
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the nuclei of stained elements?
2) What is/are the usual distinguishing color/s of the cytoplasm of stained elements?
3) What is/are the comment/s?
Given element in urinary sediment: Squamous epithelial cells
1) Dark shade of orange-purple
| 2) Light purple / blue
188
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Hyaline casts
1) Pale pink / pale purple
| 2) Very uniform color; slightly darker than mucous threads
189
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Coarse granular inclusion casts
1) Dark purple granules in purple matrix
190
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Finely granular inclusion casts
1) Fine dark purple granules in pale pink / pale purple matrix
191
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Waxy casts
1) Pale pink / pale purple
| 2) Darker than hyaline casts, but of a pale even color; distinct broken ends
192
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Fat inclusion casts
1) Fat globules unstained in a pink matrix
| 2) Rare; presence is confirmed if examination under polarized light indicates double refraction
193
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Red cell inclusion casts
1) Pink to orange-red
| 2) Intact cells can be seen in matrix
194
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Blood (hgb) casts
1) Orange-red
| 2) No intact cells
195
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Bacteria
1) Motile: do not stain; nonmotile: stain purple
| 2) Motile organisms are not impaired
196
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Trichomonas vaginalis
1) Light blue-green
| 2) Motility is unimpaired in fresh sxs when recommended volumes of stain are used; immobile organisms also identifiable
197
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Mucus
1) Pale pink / pale blue
198
Answer the ff questions w/ regards to the given element in urinary sediment:
1) What is/are the usual distinguishing color/s of the inclusions and matrix of stained elements?
2) What is/are the comment/s?
Given element in urinary sediment: Background
1) Pale pink / pale blue
199
Is cytodiagnostic urine testing part of the routine examination of the urine sediment?
No
200
In cytodiagnostic urine testing, what is done to prepare permanent slides?
Cytocentrifugation
201
What is the aid of the preparation of permanent slides using cytocentrifugation, followed by staining w/ Papanicolaou stain?
It provides an additional method for detecting and monitoring renal disease
202
True or False
Cytodiagnostic urine testing is frequently performed independently of routine UA
True
203
Cytodiagnostic urine testing is frequently performed independently of routine UA for detection of what?
For detection of malignancies of the lower urinary tract
204
What is the type of sx recommended for testing in cytodiagnostic urine testing?
First morning sx
205
What lab performs cytodiagnostic urine testing?
Cytology lab
206
What are the aids of cytodiagnostic urine testing?
1) For detection of malignancies of the lower urinary tract
2) Provides more definitive information about renal tubular changes associated w/ transplant rejection
3) Provides more definitive information about renal tubular changes associated w/ infections
a. Viral
b. Fungal
c. Parasitic
4) Provides more definitive information about renal tubular changes associated w/ cellular inclusions
5) Provides more definitive information about renal tubular changes associated w/ pathologic casts
6) Provides more definitive information about renal tubular changes associated w/ inflammatory conditions
207
What should the UA lab do to sxs w/ unusual cellular findings?
These sxs should be referred to the pathologist for further examination
208
When is microscopic examination of urine best performed?
When the laboratorian is knowledgeable about:
1) Types of microscopes available
2) The primary characteristics (of the microscopes)
3) The proper use and maintenance of these microscopes
209
What is the most common type of microscopy performed in the UA lab?
Bright-field microscopy
210
What are the other types of microscopy that are useful for examining the urine sediment?
1) Phase contrast
2) Polarizing
3) Dark field
4) Fluorescence
5) Interference contrast
211
The type of microscopy used depends on what factors?
1) Sx type
2) Refractive index of the object
3) Ability to image unstained living cells
212
All microscopes are designed to what?
To magnify small objs to such a degree that the details of their structure can be analyzed
213
How does all microscopes magnify small objects (to such a degree that the details of their structure can be analyzed)?
Basically, they do this by employing a variety of lenses and light sources
214
What are the essential components that are contained by all types of microscopes?
```
1) Lens system
Primary components:
a. Oculars
b. Objectives
c. Coarse adjustment knob
d. Fine adjustment knob
2) Illumination system
a. Light source
b. Condenser
c. Field diaphragm
d. Iris diaphragm
3) Body
a. Base
b. Body tube
c. Nosepiece
```
215
Where are the objs to be examined (via the use of microscope) placed?
These are placed on a platform (w/c is referred to as the mechanical stage)
216
What is the type of microscope that is primarily used in the UA lab?
Compound bright-field microscope
217
What are the parts of the compound bright-field microscope?
1) Two-lens system
a. First lens system (located in the objective and is adjusted to be near the sx)
b. Second lens system (the ocular lens | located in the eyepiece)
2) Light source
218
Where is the path of light (/ where does it pass through) in compound bright-field microscope?
It passes through the sx up to the eyepiece
219
Where are the oculars or eyepieces of the microscope located?
At the top of the body tube
220
True or False
Clinical lab microscopes are binocular
True
221
What is the aid of clinical lab microscopes being binocular?
It allows the examination to be performed using both eyes to provide more complete visualization
222
What can be done (to clinical lab microscopes) for optimal viewing conditions?
The oculars can be adjusted horizontally to adapt to differences in interpupillary distance between operators
223
What is the purpose of a diopter adjustment knob on the oculars?
It can be rotated to compensate for variations in vision between the operators' eyes
224
The oculars are designed to what?
To further magnify the obj that has been enhanced by the objectives for viewing
225
Lab microscopes normally contain what?
Oculars (w/c are capable of increasing the magnification 10 times [10x])
226
The field of view is determined by what?
Eyepiece
227
The field of view w/c is determined by the eyepiece is what?
It is the diameter of the circle of view (when looking through the oculars)
228
The field of view varies w/ what?
It varies w/ the:
1) Field number engraved on the eyepiece
2) Magnification of the objective
229
True or False
The higher the magnification, the smaller the field of view will be
True
230
In UA microscopy, the sediment constituents are reported as what?
As the number per microscopic field (number per hpf or lpf)
231
Where are the objectives contained / located?
These are contained in the revolving nosepiece (w/c is located above the mechanical stage)
232
What is the action done to the objectives?
These are adjusted to be near the sx and perform the initial magnification of the object on the mechanical stage
233
What happens to the image (after performing the initial magnification of the object on the mechanical stage | after adjusting the objectives to be near the sx)?
This then passes to the oculars for further resolution
234
What is resolution?
1) It is the ability to visualize fine details
| 2) It is the ability of the lens to distinguish 2 small objs that are a sp. distance apart
235
When is resolving power best?
It is best when the distance between the 2 objs is small
236
Resolving power is dependent on what?
It is dependent on the:
1) Wavelength of light
2) Numerical aperture of the lens
237
True or False
The longer the wavelength of light, the greater the resolving power of the microscope will be
False, because the shorter the wavelength of light, the greater the resolving power of the microscope will be
238
What are the objectives (and their corresponding magnifications) that are routinely used in the clinical lab?
1) Low power, dry: 10x
2) High power, dry: 40x
3) Oil immersion: 100x
239
What are the objectives used for examination of urine sediment?
1) 10x
| 2) 40x
240
How to obtain / compute for the final magnification of an object?
Objective magnification x ocular magnification
241
What is the total magnification / final magnification if a 10x ocular and a 10x objective is used and what is this observation called?
100x (w/c is called the lpf observation)
242
What is the total magnification / final magnification if a 10x ocular and a 40x objective is used and what is this observation called?
400x (w/c is called the hpf observations)
243
What is inscribed in the objectives (in the microscope)?
Objectives are inscribed w/ the info that describes:
1) Their characteristics
2) The type of objective (plan used for bright field, ph for phase contrast)
3) Their magnification
4) Their numerical aperture
5) The microscope tube length
6) The thickness of cover-slip to be used
244
The numerical aperture number represents what?
It represents the:
1) Refractive index of the material between the slide and the outer lens (air / oil)
2) Angle of the light passing through the material
245
True or False
The higher the numerical aperture, the better the light-gathering capability of the lens will be, thus yielding greater resolving power
True
246
True or False
The length of the objectives attached to the nosepiece varies w/ magnification (length increases from 10x - 100x magnification), thereby changing the distance between the lens and the slide when they are rotated
True
247
True or False
The higher the numerical aperture, the closer the lens is to the obj
True
248
Most microscopes are designed to be what?
Parfocal
249
What is the meaning of the microscope being parfocal?
It indicates that they require only minimum adjustment when switching among objectives
250
What are used to control the distance between the slide and the objective?
1) Coarse-focusing knobs
| 2) Fine-focusing knobs
251
Where are the coarse and fine-focusing knobs located?
These are located on the body tube
252
What are the actions of the coarse knob?
1) Initial focusing
| 2) Moves the mechanical stage noticeably up and down (until the obj comes into view)
253
What is the next that is used after using coarse knob?
Fine-focusing knob
254
What is the action of fine-focusing knob (after using the coarse knob)?
It sharpens the image
255
What should only be used for adjustment when changing magnifications (when using a parfocal microscope)?
Fine knob
256
What provides the illumination for the modern microscope?
Light source
257
Where is the light source located?
In the base of the microscope
258
The light source (in modern microscope) is equipped w/ what?
Rheostat
259
What is the purpose of the rheostat (w/c is equipped in the light source of the modern microscope)?
It regulates the intensity of the light
260
What may also be placed on the light source (in modern microscopes)?
Filters
261
What is the purpose of filters (that may also be placed on the light source [on compound microscope])?
To vary the illumination and wavelengths of the emitted light
262
What is contained in the light source (of a compound microscope)?
A field diaphragm
263
What is the purpose of a field diaphragm (w/c is contained in the light source [of a compound microscope])?
It controls the diameter of the light beam reaching the slide and is adjusted for optimal illumination
264
Where is the condenser located?
Below the stage
265
What are the purposes of the condenser?
1) It focuses the light on the sx
| 2) It controls the light for uniform illumination
266
What is the normal position of the condenser?
It is almost completely up w/ the front lens of the condenser near the slide but not touching it
267
What is the purpose of condenser adjustment (focus) knob?
It moves the condenser up and down to focus light on the obj
268
Where is aperture diaphragm present?
In the condenser
269
What is the purpose of the aperture diaphragm in the condenser?
It controls the amt of light and the angle of light rays that pass to the sx and lens
270
The amt of light and the angle of light rays that pass to the sx and lens affects what?
1) Resolution
2) Contrast
3) Depth
Of the field of image
271
How to achieve the maximum resolution?
By adjusting the aperture diaphragm to 75% of the numerical aperture of the objective
272
Should the aperture diaphragm be used to reduce light intensity? Why or why not?
No, because it decreases resolution
273
What is used for the adjustment (whereas the aperture diaphragm should not be used to reduce light intensity because it decreases resolution)?
Microscope lamp rheostat
274
What are the 2 adjustments to the condenser?
1) Centering
| 2) Köhler illumination
275
*What is the purpose of centering Köhler illumination?
To provide optimal viewing of the illuminated field
276
When should centering and Köhler illumination be performed?
Whenever an objective is changed
277
What is the procedure of how to center the condenser and obtain Köhler illumination?
1) Place a slide on the stage and focus the obj using the low-power objective w/ the condenser raised
2) Close the field diaphragm
3) Lower the condenser until the edges of the field diaphragm are sharply focused
4) Center the image of the field diaphragm w/ the condenser centering screws
5) Open the field diaphragm until its image is at the edge of the field
6) Remove an eyepiece and look down through the eyepiece tube
7) Adjust the aperture diaphragm until approx 75% of the field is visible
8) Replace the eyepiece
278
What are parts (of the microscope) that should be used for additional focusing of the obj?/
1) Adjustment knobs
| 2) Rheostat (on the light source)
279
How to ensure good optical performance (of the microscope)?
Via doing routine preventive maintenance procedures on the microscope
280
What should be done to the microscope when not in use and what is its purpose?
It should always be covered when not in use to protect it from dust
281
What should be done if any optical surface (of the microscope) becomes coated w/ dust?
It should be carefully removed w/ a camel-hair brush
282
What should be done to optical surfaces (of the microscope)?
These should be cleaned w/ lens paper
283
What should be done to any contaminated lens (in the microscope)?
These should be cleaned w/ a commercial lens cleaner
284
What are the actions that must be done to the oil immersion lens (of the microscope) after each use?
1) It must be wiped free of oil
| 2) It must be cleaned
285
What is the effect of fingerprints and oil smears?
These impair the sharpness of an image
286
What is recommended to be done (/ how often should it be done)? to the microscope?
The microscope should have an annual professional cleaning
287
True or False
Light sources (of the microscope) are replaced as necessary
True
288
What is the fxn of the given UA microscopic technique?
Given UA microscopic technique: Bright-field microscopy
Used for routine UA
289
What is the fxn of the given UA microscopic technique?
Given UA microscopic technique: Phase-contrast microscopy
Enhances visualization of elements w/ low refractive indices such as:
1) Hyaline casts
2) Mixed cellular casts
3) Mucous threads
4) Trichomonas
290
What is the fxn of the given UA microscopic technique?
Given UA microscopic technique: Polarizing microscopy
Aids in identification of chole in oval fat bodies, fatty casts, and crystals
291
What is the fxn of the given UA microscopic technique?
Given UA microscopic technique: Dark-field microscopy
Aids in identification of Treponema pallidum
292
What is the fxn of the given UA microscopic technique?
Given UA microscopic technique: Fluorescence microscopy
Allows visualization of naturally fluorescent microorganisms or those stained by a fluorescent dye including labeled Ags and Abs
293
What is the fxn of the given UA microscopic technique?
Given UA microscopic technique: Interference-contrast
Produces a three-dimensional microscopy image and layer-by-layer imaging of a sx
294
What are the parts of the binocular microscope?
1) Interpupillary distance control
2) Ocular
3) Body
4) Condenser focus knob
5) Course adjustment knob
6) Fine adjustment knob
7) Mechanical stage adjustment knobs
8) Nosepiece
9) Objective
10) Condenser aperture diaphragm control ring
11) Condenser
12) Centering screw
13) Field diaphragm control ring
14) Rheostat
295
What are the things that should be done to take care of the microscope?
1) Carry microscope w/ 2 hands (supporting the base w/ 1 hand)
2) Always hold the microscope in a vertical position
3) Clean optical surfaces only w/ a good quality lens tissue and commercial lens cleaner
4) Do not use the 10x and 40x objectives w/ oil
5) Clean the oil immersion lens after use
6) Always remove slides w/ the low-power objective raised
7) Store the microscope w/ the low-power objective in position and the stage centered
296
What are the different types of microscopy?
1) Bright-Field microscopy
2) Phase-contrast microscopy
3) Polarizing microscopy
4) Interference-contrast microscopy
5) Dark-field microscopy
6) Fluorescence microscopy
297
What is the principle of bright-field microscopy?
Objs appear dark against a light bg
298
What type of microscopy is most frequently used in the clinical lab?
Bright-field microscopy
299
What does bright-field microscopy (/ technique) employ?
It is a basic microscope w/ a light source (w/c emits light in the visible wavelength range)
300
Can the use of bright-field microscopy present problems in the the examination of urine sediments? If yes, when? If no, why?
Yes, when the amt of light reaching the sx is not properly controlled
301
What is the effect of the problem that can arise (in terms of examination of the urine sediments) if bright-field microscopy is used?
Sediment constituents w/ a low refractive index will be overlooked when subjected to light of high intensity
302
Due to the effect that can arise (in terms of examination of the urine sediments) if bright-field microscopy is used, what is the resolution that must be done to assess this problem?
Sediments must be examined using decreased light
303
How to properly control the light (in connection to the resolution to the problem that can arise in terms of examination of urine sediments [if bright-field microscopy is used])?
Via adjusting the rheostat on the light source, not by lowering the condenser
304
What is the aid of staining of the sediment (in bright-field microscopy | in terms of examination of urine sediments)?
Staining of the sediment also increases the visualization of the urine sediments / elements
305
What is phase difference (/ what is the principle of phase difference)?
As light rays pass through an obj, they are slowed in comparison to the rays passing through air (media), thereby decreasing the intensity of the light and producing contrast
306
What are the factors that affect phase difference?
1) Thickness of the obj
2) Refractive index
3) Other light-absorbance properties
307
When is the best contrast obtained (in phase-contrast microscopy) and what type of microscopy provides this contrast?
It is obtained when the light that does not pass through the sx is shifted 1 quarter of a wavelength and compared w/ the phase difference of the sx
This is provided by phase-contrast microscopy
308
How is phase-contrast microscopy accomplished?
It is accomplished by adaptation of a bright-field microscope w/ a phase contrast objective lens and a matching condenser
Bright-field microscope (adapted) + phase contrast objective lens + matching condenser
309
What are placed in the condenser and the objective (in phase-contrast microscopy)?
Two phase rings (that appear as "targets")
310
Where is one phase ring placed (in phase-contrast microscopy)?
In the condenser or below it
311
What is the action of 1 phase ring (w/c is placed in the condenser or below it)?
It permits light to only pass through the central clear circular area
312
Where is a second phase-shifting ring (w/ a central circular area that retards light by 1 quarter wavelength) placed (in phase-contrast microscopy)?
In the objective
313
True or False
Phase rings must match (in phase-contrast microscopy)
True
314
Since phase rings must match (in phase-contrast microscopy), what should be done?
It is impt to check that the objective and condenser mode are the same
315
True or False
The diameter of the rings varies w/ the magnification (in phase-contrast microscopy)
True
316
When is the image (in phase-contrast microscopy) have the best contrast?
When the bg is darkest
317
What must be done to have maximum contrast (in phase-contrast microscopy)?
Phase-contrast rings must be adjusted
318
True or False
The 2 rings are adjusted to make them concentric (in phase-contrast microscopy)
True
319
What is the method of adjustment steps (of the phase-contrast rings | to have a maximum contrast | in phase-contrast microscopy)?
1) Focus the microscope in bright-field w/ a sx slide
2) Select a low-power phase condenser ring
3) Select the corresponding ring objective
4) Remove an ocular, insert the adjustment telescope, and look through the telescope
5) Observe the dark and light rings (annuli)
6) W/ the adjusting screw on the telescope, center the light annulus (condenser) over the dark annulus (objective)
7) Replace the ocular
320
*What is the principle of phase-contrast microscopy?
Light passes to the sx through the clear circle in the phase ring in the condenser, forming a halo of light around the sx. The diffracted light then enters the central circle of the phase-shifting ring, and all other light is moved 1 quarter of a wavelength out of phase. The variations of contrast in the sx image due to the various refractive indexes in the obj are observed as the light rays merge together, enhancing visualization and detail
321
What is the advantage of using phase-contrast microscopy?
It is particularly advantageous for identifying:
1) Low refractive hyaline casts
2) Or mixed cellular casts
3) Mucous threads
322
The use of polarized light (in polarizing microscopy) aids in the identification of what components / urine sediments?
1) Crystals
| 2) Lipids
323
What are the characteristics of crystals and lipids?
1) Both substances have the ability to rotate the path of the unidirectional polarized light beam to produce:
a. Characteristic colors in crystals
b. Maltese cross formation in lipids
2) These are birefringent
324
What is birefringent?
It is a property indicating that the element can refract light in 2 dimensions at 90 degrees to each other
325
What produces light rays of many different waves (in polarizing microscopy)?
The halogen quartz lamp (in the microscope)
326
What is the characteristic of each wave (since the light rays [produced by the halogen quartz lamp in the microscope] have many different waves)?
Each has a distinct direction and a vibration perpendicular to its direction
327
True or False
In polarizing microscopy, normal or unpolarized light vibrates in equal intensity in all directions
True
328
What is the characteristic of polarized light (in polarizing microscopy)?
It vibrates in the same plane / direction
329
What happens as the light passes through a birefringent substance (in polarizing microscopy)?
It splits into 2 beams (1 beam rotated 90 degrees to the other)
330
Provide an ex of isotropic substances
Blood cells
331
What is the characteristic of blood cells?
*They do not have the refractive property (/ birefringence) and the light passes through unchanged
332
What is the principle of positive birefringence?
A substance that rotates the plane of polarized light 90 degrees in a clockwise direction
333
What is the principle of negative birefringence?
A substance that rotates the plane in a counterclockwise direction
334
How to obtain the polarized light (in polarizing microscopy)?
By using 2 polarizing filters
335
What is the principle of action of the 2 polarizing filters (in polarizing microscopy)?
The light emerging from 1 filter vibrates in 1 plane, and a 2nd filter placed at a 90-degree angle blocks all incoming light, except that rotated by the birefringent substance
336
True or False
The 2 polarizing filters are in opposite directions called a "crossed configuration" (in polarizing microscopy)
True
337
True or False
Between cross-polarizing filters, birefringent crystals are not visible in characteristic patterns
False, because between cross-polarizing filters, birefringent crystals are visible in characteristic patterns
338
True or False
Bright-field microscopes can be adapted for polarizing microscopy
True
339
True or False
2 polarizing filters must be installed in a cross configuration (in polarizing microscopy)
True
340
What is the 1st filter (w/c must be installed in a cross configuration | in polarizing microscopy)?
The polarizing filter
341
Where is the polarizing filter placed (in polarizing microscopy)?
In the condenser filter holder
342
What is the 2nd filter (w/c must be installed in a cross configuration | in polarizing microscopy)?
The analyzer
343
Where is the analyzer placed (in polarizing microscopy)?
In the head between the objectives and the ocular
344
What is the action done to the polarizing filter and what is its purpose?
It is rotated to allow light vibrating in 1 direction only to reach the obj
345
After rotating the polarizing filter, what are the things that will happen if the obj does not have birefringent properties (in polarizing microscopy)?
1) No light will reach the analyzer filter
| 2) The obj will appear black
346
*After rotating the polarizing filter, what will happen (in polarizing microscopy)?
Refracted rays from a birefringent obj will reach the analyzer, causing the obj to appear white or colored against the black bg
347
What is the additional filter that can be added to the microscope (in polarizing microscopy)?
A red compensated polarizing filter
348
What is the action of the red compensating polarizing filter (in polarizing microscopy)?
It divides the light entering the microscope into slow and fast vibrations
349
What is the aid of aligning the crystals w/ the slow vibration (via the use of the red compensated polarizing filter | in polarizing microscopy)?
Crystals can be more easily identified
350
What is the color that crystals produce (if they are aligned w/ the slow vibration [via the use of the red compensated polarizing filter] | in polarizing microscopy)?
Blue / yellow
351
What are the uses of polarizing microscopy in UA?
1) To confirm the identification of:
a. Fat droplets
b. Oval fat bodies
c. Fatty casts
2) To distinguish birefringent uric acid crystals from cystine crystals (by their polarizing characteristics)
3) To distinguish monohydrate calcium oxalate crystals from nonpolarizing RBCs (by their polarizing characteristics)
4) To distinguish calcium phosphate crystals from nonpolarizing bacteria (by their polarizing characteristics)
352
What is the characteristic of fat droplets, oval fat bodies, and fatty casts (in UA)?
These produce a characteristic Maltese cross pattern
353
What is the principle of interference-contrast microscopy?
It provides a three-dimensional image showing very fine structural detail by splitting the light ray so that the beams pass through different areas of the sx. The light interference produced by the varied depths of the sx is compared, and a three-dimensional image is visualized
354
What is the advantage of interference-contrast microscopy?
An obj appears bright against a dark bg but w/out the diffraction halo associated w/ phase-contrast microscopy
355
What are required to perform interference-contrast microscopy?
More extensive modifications to the bright-field microscope
356
True or False
Since more extensive modifications to the bright-field microscope are required to perform interference-contrast microscopy, hence, interference-contrast microscopy is not routinely used in the UA lab
True
357
What are the 2 types of interference-contrast microscopy that are available?
1) Modulation contrast (Hoffman)
| 2) Differential-interference contrast (Nomarski)
358
Can bright-field microscopes be adapted for both methods (of both types of interference-contrast microscopy)?
Yes
359
What are the components present in the modulation-contrast microscope?
1) A split aperture
2) A polarizer
3) An amplitude filter
360
Where is the split aperture placed (in the modulation-contrast microscope | in interference-contrast microscopy)?
Below the condenser
361
Where is the polarizer placed (in the modulation-contrast microscope | in interference-contrast microscopy)?
Below the split aperture
362
Where is the amplitude filter placed (in the modulation-contrast microscope | in interference-contrast microscopy)?
In back of each objective
363
True or False
The modulator (in interference-contrast microscopy) has 4 zones of light transmission
False, because the modulator (in interference-contrast microscopy) has 3 zones of light transmission
364
What are the 3 zones of light transmission (in interference-contrast microscopy)?
1) A dark zone
2) A gray zone
3) A clear zone
365
The dark zone transmits how many percentage of light?
1%
366
The gray zone transmits how many percentage of light?
15%
367
The clear zone transmits how many percentage of light?
100%
368
What is the action of polarized light rays (in phase-contrast microscopy)?
It pass through a split aperture to the various areas of the sx and to the modulator where they are converted into the variations of light intensity to produce a three-dimensional image
369
True or False
The differential interference-contrast microscope uses prisms
True
370
What is placed between the light source and condenser (in interference-contrast microscopy)?
A polarizing filter to output plane-polarized light
371
What is the action of two-layered Nomarski-modified Wollaston prism (in interference-contrast microscopy)?
It separates the individual rays of light into ray pairs is required
372
Where is the lower Wollaston prism built into the microscope (in interference-contrast microscopy)?
Into the condenser of the microscope
373
Where is the upper prism placed and what is its action (in interference-contrast microscopy)?
Between the objective and the eyepiece and recombines the rays
374
True or False
Above the top Wollaston prism, another polarizing filter is placed that causes wave interference to occur and produce the three-dimensional image (in interference-contrast microscopy)
True
375
*True or False
These two types of microscopy provide layer-by-layer imaging of a sx and enhanced detail for sxs w/ either a low or high refractive index
True
376
What is dark-field microscopy?
It is a technique used in the clinical lab to enhance visualization of sxs that cannot be easily viewed w/ a bright-field microscope
377
At what type of sxs is dark-field microscopy often used?
Unstained sxs
378
What is the particular organism (to be identified) where dark-field microscopy is often used?
Spirochete Treponema pallidum
379
Is a bright-field microscope easily adapted for dark-field microscopy? If yes, how? If no, why?
Yes, by replacing the condenser w/ a dark-field condenser that contains an opaque disk
380
What is the action of the disk (specifically the opaque disk that is contained in a dark-field condenser)?
It blocks the light from directly entering the objective, and the field of view is black
381
What is the principle of dark-field microscopy?
As the light rays pass through the sx at oblique angles, the light scatters, diffracts, or reflects off the sx and is captured by the objective lens. The sx appears light against the black bg or dark-field
382
What is fluorescence microscopy?
It is a rapidly expanding technique used in the medical field today
383
What is the use of fluorescence microscopy?
It is used to detect bacteria and viruses within cells and tissues through a technique called immunofluorescence
384
What is fluorescence? (in fluorescence microscopy)?
It is the property by w/c some atoms absorb light at a particular wavelength and subsequently emit light of a longer wavelength, termed fluorescence lifetime
385
What is the practical application / principle of fluorescence microscopy in the lab?
It allows the visualization of naturally fluorescent substances / those that have been stained w/ a fluorochrome / fluorophore (fluorescent dyes) to produce an image. The sx is illuminated w/ a light of a sp. wavelength. Fluorescent substances absorb the energy and emit a longer wavelength of light that is visualized w/ the use of special filters, called the excitation filter and the emission filter. The excitation filter selects the excitation wavelength of light from a light source. The emission filter selects a sp. wavelength of emitted light from the sx to become visible. The filters are chosen to match the excitation and emission wavelengths of the fluorophore used to label the sx. A dichroic mirror reflects the excitation light to the sx and transmits the emitted light to the emission filter, w/c is collected w/ the objective and imaged by the detector. The fluorescent substance can be observed in the fluorescent microscope as a bright obj against a dark bg w/ high contrast when ultraviolet light source is used
386
What are the 2 special filters that are used (to visualize the light [present in a longer wavelength] emitted by the fluorescent substances)?
1) Excitation filter
| 2) Emission filter
387
What is the fxn of excitation filter (in fluorescence microscopy)?
It selects the excitation wavelength of light from a light source
388
What is the fxn of emission filter (in fluorescence microscopy)?
It selects a sp. wavelength of emitted light from the sx to become visible
389
What are the fxns of a dichroic mirror (in fluorescence microscopy)?
1) It reflects the excitation light to the sx
| 2) It transmits the emitted light to the emission filter
390
True or False
Powerful light sources are required (in fluorescence microscopy)
True
391
What are the powerful light sources (w/c are required in fluorescence microscopy)?
Either:
1) Mercury lamp
2) Or xenon arc lamp
392
True or False
A normal urine sediment may not contain a variety of formed elements
False, because a normal urine sediment may contain a variety of formed elements
393
True or False
Even the appearance of small #s of the usually pathologically significant RBCs, WBCs, and casts can be normal
True
394
True or False
Since even the appearance of small #s of the usually pathologically significant RBCs, WBCs, and casts can be normal, likewise, many routine urine sxs contain nothing more than a rare epithelial cell or mucous strand
True
395
What are the factors that can easily distort cellular elements (w/c makes identification more difficult)?
1) Widely varying concs.
2) pH
3) Presence of metabolites (in the urine)
396
True or False
Actual normal numerical values (of urine sediments) are clearly defined
False, because actual normal numerical values (of urine sediments) are not clearly defined
397
What is the purpose of urine sediment preparation methods (since actual normal numerical values are not clearly defined [in urine sediments])?
These determine the actual conc. of the sediment, and, therefore, the # of elements that may be present in a microscopic field
398
What are the commonly listed values (of urine sediments | in terms of reporting)?
1) 0 - 2 RBCs/hpf
2) 0 - 3 RBCs/hpf
3) 0 - 5 WBCs/hpf
4) 0 - 8 WBCs/hpf
5) 0 - 2 hyaline casts/lpf
399
Such commonly listed values (in terms of reporting) must be taken in context w/ other factors such as what?
Such as:
1) Recent stress
2) Recent exercise
3) Menstrual contamination
4) Presence of other urine sediment constituents
400
*What are the urine sediment constituents that can be seen via microscopic observation of urine?
1) RBCs
2) WBCs
a. Neutrophils
b. Eosinophils
c. Mononuclear cells
i. Lymphocytes
ii. Monocytes
iii. Macrophages
iv. Histiocytes
3) Epithelial cells
a. Squamous epithelial cells
b. Transitional epithelial (urothelial) cells
c. Renal tubular epithelial (RTE) cells
d. Oval fat bodies
Miscellaneous structures:
4) Bacteria
5) Yeast
6) Parasites
7) Spermatozoa
8) Mucus
9) Casts
a. Hyaline casts
b. RBC casts
c. WBC casts
d. Bacterial casts
e. Epithelial cell casts
f. Fatty casts
g. Mixed cellular casts
h. Granular casts
i. Waxy casts
j. Broad casts
```
Urinary crystals
Normal crystals seen in acidic urine:
10) Uric acid crystals
11) Amorphous urates
12) Calcium oxalate crystals
a. Dihydrate calcium oxalate crystals
b. Monohydrate calcium oxalate crystals
Normal crystals seen in alkaline urine:
13) Amorphous phosphates
14) Calcium phosphate crystals
15) Triple phosphate crystals
16) Ammonium biurate crystals
17) Calcium carbonate crystals
Abnormal urine crystals:
18) Cystine crystals
19) Cholesterol crystals
20) Radiographic dye crystals
Crystals associated w/ liver disorders (abnormal urine crystals):
21) Tyrosine crystals
22) Leucine crystals
23) Bilirubin crystals
24) Sulfonamide crystals / sulfonamides
25) Ampicillin crystals
```
Urinary sediment artifacts
26) Starch
27) Oil droplets
28) Air bubbles
29) Pollen grains
30) Fibers
31) Fecal contamination
401
What are the characteristics of RBCs (as urine sediment)?
1) Smooth
2) Non-nucleated
3) Biconcave disks
4) Measuring approx 7 mm (in diameter)
402
What is the objective that must be used to identify RBCs?
High-power (40x) objective (x400 magnification)
403
How are RBCs routinely reported?
Average number seen in 10 hpfs
404
What are the characteristics of RBCs in concentrated (hypersthenuric) urine?
1) These shrink (due to loss of H2O)
| 2) These may appear crenated or irregularly shaped
405
What are the characteristics of RBCs in dilute (hyposthenuria) urine?
1) These absorb H2O
2) These swell
3) These lyse rapidly (releasing their hgb and leaving only the cell membrane)
406
What are ghost cells (/ what are its characteristic)?
1) These are large empty cells
| 2) These can be easily missed (if sxs are not examined under reduced light)
407
Among all of the urine sediments, what are the sediment that are the most difficult for students to recognize?
RBCs
408
Why are RBCs the sediment that are the most difficult to be recognized for students?
1) Because RBCs' lack of characteristic structures
2) Because RBCs' lack of variations in size
3) Because RBCs' have close resemblance to other urine sediment constituents
409
*RBCs are frequently confused w/ what sediments?
1) Yeast cells
2) Oil droplets
3) Air bubbles
410
As a point of differentiation (w/ RBCs), what is the characteristic of yeast cells?
They usually exhibit budding
411
As a point of differentiation (w/ RBCs), what are the characteristics of oil droplets and air bubbles?
1) Both of these are highly refractile (when the fine adjustment is focused up and down)
2) They may also appear in a different plane than other sediment constituents
412
What is the characteristic of crenated RBCs?
They have rough appearance
413
The characteristic of crenated RBCs may resemble what?
It may resemble the granules seen in WBCs, but they are much smaller than WBCs
414
If the identification of RBCs continue to be doubtful, what should / can be done and what is the effect of this action?
Adding acetic acid to a portion of the sediment will lyse the RBCs, leaving the yeast, oil droplets, and WBCs intact
415
Aside from adding acetic acid to a portion of the sediment (w/c should / can be done if identification of RBCs continue to be doubtful), what may also be used w/c may also be hepful?
Supravital staining
416
True or False
Studies have focused on the morphology of urinary RBCs as an aid in determining the site of renal bleeding
True
417
What are dysmorphic RBCs (/ what are its characteristics)?
These are RBCs that:
1) Vary in size
2) Have cellular protrusions
3) Or are fragmented
4) Have been associated primarily w/ glomerular bleeding%
5) Have also been demonstrated after strenuous exercise (indicating a glomerular origin of this phenomenon)
418
Should the # and appearance of dysmorphic cells must also be considered? Why or why not?
Yes, because abnormal urine conc. affects RBC appearance, and small #s of dysmorphic cells are found w/ nonglomerular hematuria
419
What are the characteristics of dysmorphic RBCs (w/c are most closely associated w/ glomerular bleeding)?
1) These appears to be acanthocyte
2) W/ multiple protrusions
3) These may be difficult to be observed (under bright-field microscopy)
420
Further analysis of sediments containing dysmorphic RBCs using Wright's stained preparations shows the cells to be what?
Shows the cells to be hypochromic and better delineates the presence of cellular blebs and protrusions
421
What are the clinical significance of RBCs in the urine?
1) These are associated w/ damage to the glomerular membrane
2) These are associated w/ vascular injury within the GUT
422
As a part of clinical significance of RBCs in the urine, the number of RBCs present is indicative of what?
It is indicative of the extent of the damage or injury
423
As a part of clinical significance (of RBCs), what is the aid of pt histories?
These often mention the presence of macroscopic vs. microscopic hematuria
424
What are the characteristics of urine if macroscopic hematuria is present?
1) Urine appears cloudy
| 2) Urine has a red to brown color
425
True or False
Microscopic analysis (of RBCs) may be reported in terms of > 100/hpf or as specified by the lab protocol
True
426
Macroscopic hematuria is frequently associated w/ what (as part of clinical significance of RBCs)?
Advanced glomerular damage
427
Macroscopic hematuria is frequently associated w/ advanced glomerular damage (as part of clinical significance of RBCs), but it is also seen in what condition / disorder?
It is also seen w/ damage to the vascular integrity of the urinary tract caused by:
1) Trauma
2) Acute infection or inflammation
3) Coagulation disorders
428
The observation of microscopic hematuria can be critical to what (as part of clinical significance of RBCs)?
It can be critical to:
1) Early dx of glomerular disorders
2) Early dx of malignancy of the urinary tract
3) Confirm the presence of renal calculi
429
Aside from RBCs as being present in the urine sediment w/c may be seen following strenuous exercise, what are the other sediment constituents that may also be seen in the urine sediment?
1) Hyaline casts
2) Granular casts
3) RBC casts
430
True or False
The presence of hyaline, granular, and RBC casts in the urine sediment (following strenuous exercise) is abnormal and pathologic
False, because the presence of hyaline, granular, and RBC casts in the urine sediment (following strenuous exercise) is abnormal and nonpathologic
431
Does the presence of hyaline, granular, and RBC casts in the urine sediment (following strenuous exercise) disappear? If yes, when? If no, why?
Yes, after rest
432
As part of clinical significance of RBCs, what must also be considered in female pts?
Possibility of menstrual contamination
433
Is the presence / absence of RBCs in the urine sediment can always be correlated w/ sx color / a (+) chemical test result for blood?
No, because the presence / absence of RBCs in the urine sediment cannot always be correlated w/ sx color / a (+) chemical test result for blood?
434
Why is hgb present in the urine sediment (as part of clinical significance of RBCs)?
Because hgb has been filtered by the glomerulus
435
What are the indicators that hgb is present in the urine (/ hgburia | as a part of clinical significance of RBCs)?
1) Presence of red urine
| 2) Presence of (+) chemical test result for blood (in the absence of microscopic hematuria)
436
True or False
Like in the principle of hgburia (specifically the indicators of presence of hgburia), a sx appearing microscopically normal may contain a small but pathologically significant # of RBCs when examined microscopically
True
437
Answer the ff questions w/ regards to the given urinary sediment constituent:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given urinary sediment constituent: RBCs
1) a. Non-nucleated biconcave disks
b. Crenated (in hypertonic urine)
c. Ghost cells (in hypotonic urine)
d. Dysmorphic (w/ glomerular membrane damage)
2) a. Yeast cells
b. Oil droplets
c. Air bubbles
3) Average number per 10 hpfs
4) a. Color
b. Rgnt strip blood rxn
438
What are the characteristics of WBCs (as a urinary sediment constituent)?
1) These are larger than RBCs
| 2) These measure an average of about 12 mm (in diameter)
439
What is the predominant WBC found in the urine sediment?
Neutrophil
440
True or False
Neutrophils are much easier to identify than RBCs
True
441
Why are neutrophils much easier to identify than RBCs?
Because they contain:
1) Granules
2) Multilobed nuclei
442
What is the objective used to identify neutrophils?
High-power objective (/ high-power microscopy)
443
How are WBCs reported (/ what is the manner of reporting of WBCs)?
Average number seen in 10 hpfs (like in the manner of reporting for RBCs)
444
What are the characteristics of neutrophils (in dilute alkaline urine)?
1) These lyse rapidly
| 2) These begin to lose nuclear detail
445
What are the characteristics of neutrophils (in hypotonic urine)?
1) These absorb H2O
| 2) These then swell
446
What are glitter cells (/ what is the principle of glitter cells)?
The brownian movement of the granules of neutrophils within these larger cells (neutrophils) produces a sparkling appearance w/c are referred to as glitter cells
447
What is the characteristic of glitter cells when these are stained w/ Sternheimer-Malbin stain?
These large cells stain light blue (as opposed to the violet color usually seen w/ neutrophils)
448
Are glitter cells pathologically significant?
No
449
The presence of urinary eosinophils is primarily associated w/ what condition / disorder?
Drug-induced interstitial nephritis
450
At what conditions / disorders small #s of eosinophils may be seen?
1) UTI
| 2) Renal transplant rejection
451
What is required to be done for performing a urinary eosinophil test?
Evaluation of a concentrated, stained urine sediment
452
How may the urine sediment be concentrated?
Via:
1) Routine centrifugation (alone)
2) Or cytocentrifugation
453
What is the preferred eosinophil stain?
Hansel
454
Aside from Hansel stain, what is the other stain that can also be used as an eosinophil stain?
Wright's stain
455
True or False
The percentage of eosinophils in 100 - 500 cells is determined
True
456
Are eosinophils normally seen in the urine?
No
457
Since eosinophils are not normally seen in the urine, is the finding of > 1% eosinophils considered significant?
Yes
458
What are the mononuclear cells (in the urine sediment)?
1) Lymphocytes
2) Monocytes
3) Macrophages
4) Histiocytes
459
What are the characteristics of the mononuclear cells?
1) These may be present in small #s
| 2) These are usually not identified (in the wet preparation urine microscopic analysis)
460
What is the characteristic of lymphocytes?
These are the smallest WBCs
461
Due to the characteristic of lymphocytes, they may resemble as what urinary sediment constituent?
RBCs
462
When are increased #s of mononuclear cells may be seen (/ what is the condition / disorder where increased #s of mononuclear cells may be seen)?
In early stages of renal transplant rejection
463
What are the characteristics of monocytes, macrophages, and histiocytes?
1) Large cells
2) May appear vacuolated
3) Or contain inclusions
464
What should be done to sxs containing an increased amt of mononuclear cells that cannot be identified as epithelial cells?
These should be referred for cytodiagnostic urine testing
465
What is the primary concern in the identification of WBCs?
Differentiation of mononuclear cells and disintegrating neutrophils from round RTE cells
466
To assess the primary concern in the identification of WBCs, what are the characteristics of RTE cells?
1) These are usually larger than WBCs
| 2) These have an eccentrically located nucleus
467
What is the characteristic of WBCs in the process of ameboid motion?
These may be difficult to distinguish from epithelial cells
468
Why are WBCs in the process of ameboid motion may be difficult to distinguish from epithelial cells?
Because of their irregular shape
469
What are the things that can be done to enhance the nuclear detail (of WBCs | if necessary | since WBCs [in the process of ameboid action] may be difficult to distinguish from epithelial cells)?
1) Supravital staining
| 2) Addition of acetic acid
470
How many (usually) leukocytes/hpf are found in normal urine?
Fewer than 5 leukocytes/hpf
471
True or False
Higher #s of leukocytes may be present in urine from males
False, because higher #s of leukocytes may be present in urine from females
472
What are the characteristics of leukocytes?
1) They may enter the urine through glomerular or capillary trauma (like RBCs)
2) They are also capable of ameboid migration through the tissues to the sites of infection / inflammation
473
What is pyuria?
It is a condition whereas there is an increase in urinary WBCs
474
Pyuria indicates what?
It indicates the presence of infection or inflammation in the GU system
475
What are the frequent causes of pyuria?
Bacterial infections such as:
1) Pyelonephritis
2) Cystitis
3) Prostatitis
4) Urethritis
476
Since various bacterial infections are the frequent causes of pyuria, at what conditions / disorders is pyuria also present?
In nonbacterial disorders such as:
1) Glomerulonephritis
2) Lupus erythematosus
3) Interstitial nephritis
4) Tumors
477
True or False
Reporting the presence of bacteria in sxs containing leukocytes is not impt
False, because reporting the presence of bacteria in sxs containing leukocytes is impt
478
Answer the ff questions w/ regards to the given urinary sediment constituent:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given urinary sediment constituent: WBCs
1) a. Larger than RBCs
b. Granulated, multilobed neutrophils
c. Glitter cells (in hypotonic urine)
d. Mononuclear cells w/ abundant cytoplasm
2) Renal tubular epithelial cells
3) Average number per 10 hpfs
4) a. LE
b. Nitrite
c. SG
d. pH
479
Is it unusual to find epithelial cells in the urine? Why or why not?
No, it is not unusual to find epithelial cells in the urine, because they are derived from the linings of the genitourinary system
480
Epithelial cells in the urine represent what?
They represent normal sloughing of old cells (unless they are present in large #s or in abnormal forms)
481
What are the 3 types of epithelial cells that are seen in urine?
1) Squamous
2) Transitional (urothelial)
3) Renal tubular
482
The 3 types of epithelial cells seen in the urine are classified accdg to what?
They are classified accdg to their site of origin within the genitourinary system
483
What is the largest cells found in the urine sediment?
Squamous cells (/ squamous epithelial cells)
484
What are the characteristics of squamous epithelial cells?
They contain:
1) Abundant, irregular cytoplasm
2) A prominent nucleus (about the size of an RBC)
485
What are often the 1st structures observed when the urine sediment is examined under low-power magnification?
Squamous epithelial cells
486
True or False
Usually at least a few squamous epithelial cells are present in the urine sediment
True
487
What is the aid of presence of few squamous epithelial cells (usual) in the urine sediment?
It can serve as a good reference for focusing of the microscope
488
After examination of the appropriate number of fields, how are squamous epithelial cells commonly reported?
1) Rare
2) Few
3) Moderate
4) Many
489
How are squamous epithelial cells reported?
They are reported in terms of low-power or high-power magnification (based on lab protocol)
490
True or False
Difficulty identifying squamous cells is rare
True
491
Even if the difficulty of identifying squamous cells is rare, what are the characteristics of squamous cells that may make identifying squamous cells difficult?
1) They may appear folded, possibly resembling a cast
| 2) It will begin to disintegrate in urine that is not fresh
492
In urine sediments containing large amts of squamous cells, what may make it more difficult to enumerate smaller pathologic elements (such as RBC and WBCs)?
Clumps of cells (w/c should be carefully examined)
493
Where does squamous epithelial cells originate?
1) From the linings of the vagina
2) From the linings of female urethra
3) From the lower portion of the male urethra
494
What does squamous epithelial cells represent?
They represent normal cellular sloughing
495
Does squamous epithelial cells have pathologic significance?
No, they don't have pathologic significance
496
At what gender are increased amts of squamous epithelial cells more frequently seen in the urine?
Female pts
497
What is the procedure / type of sx that contain less squamous cell contaimation?
Sxs collected using midstream clean-catch technique
498
What is clue cell?
It is a variation of the squamous epithelial cell
499
Do clue cells have pathologic significance?
Yes
500
Clue cells are indicative of what condition / disorder?
Vaginal infection
501
What is the bacterium that causes vaginal infection (where clue cells are indicative of)?
Bacterium Gardnerella vaginalis
502
What is the characteristic of clue cells?
They appear as squamous epithelial cells covered w/ the Gardnerella coccobacillus
503
How to consider a squamous epithelial cell as a clue cell?
The bacteria should cover most of the cell surface and extend beyond the edges of the cell
504
Since the bacteria should cover most of the cell surface and extend beyond the edges of the cell (to be considered as a clue cell), what are the characteristics that this phenomena gives?
This gives the cell a granular, irregular appearance
505
How is routine testing for clue cells performed?
This is performed via examining a vaginal wet preparation for the presence of the characteristic cells
506
Since routine testing for clue cells is performed by examining a vaginal wet preparation, are small #s of clue cells may be present in the urinary sediment?
Yes
507
What should be observed / done by microscopists in terms of examination of clue cells?
Microscopists should remain alert for their presence , as UA may be the 1st test performed on the pt
508
What are the characteristics of transitional epithelial cells?
1) These are smaller than squamous cells
2) These appear in several forms including:
a. Spherical
b. Polyhedral
c. Caudate
509
The differences of the characteristics of transitional epithelial (urothelial) cells are caused by what (/ what is the principle of the differences of the characteristics)?
These are caused by the ability of transitional epithelial cells to absorb large amts of H2O. Cells in direct contact w/ the urine absorb H2O, becoming spherical in form and much larger than the polyhedral and caudate cells
510
True or False
All forms of transitional epithelial (urothelial) cells have distinct, eccentrically located nuclei
False, because all forms of transitional epithelial (urothelial) cells have distinct, centrically located nuclei
511
At what magnification (/ what objective is used) are transitional cells (/ transitional epithelial cells) identified and enumerated?
High-power magnification (/ hpf / hpo)
512
How are transitional epithelial cells usually reported?
They are usually reported as (like in reporting of squamous cells | following lab protocol):
1) Rare
2) Few
3) Moderate
4) Many
513
What is the characteristic of spherical forms of transitional epithelial cells?
These are sometimes difficult to distinguish from RTE cells
514
What are the characteristics (/ what can be done) of spherical forms of transitional epithelial cells that can aid w/ its differentiation from RTE cells?
1) Presence of centrally located rather than eccentrically placed nucleus
2) Supravital staining
515
Where do transitional epithelial cells originate?
They originate from:
1) Lining of renal pelvis
2) Lining of calyces
3) Lining of ureters
4) Lining of bladder
5) Upper portion of the male urethra
516
True or False
Transitional epithelial cells are usually present in small numbers in normal urine, representing normal cellular sloughing
True
517
At what condition / disorder are increased #s of transitional cells (seen in singly, in pairs, / in clumps [syncytia]) present?
These are present following invasive urologic procedures such as catheterization
518
Are increased #s of transitional cells (seen in singly, in pairs, / in clumps) w/c are present following invasive urologic procedures clinically significant?
No, these are of no clinical significance
519
An increased in transitional cells exhibiting abnormal morphology (such as vacuoles and irregular nuclei) may be indicative of what conditions / disorders?
1) Malignancy
| 2) / viral infection
520
What should be done when there is an increase in transitional cells exhibiting abnormal morphology?
The sx should be referred to the pathologist
521
What are the characteristics of RTE cells?
1) These vary in:
a. Size
b. Shape
2) These often resemble casts
522
RTE cells vary in size and shape depending on what?
Depending on the area of the renal tubules from w/c they originate
523
What are the characteristics of cells from the proximal convoluted tubule (PCT)?
1) These are larger than other RTE cells
2) They tend to have a rectangular shape (and are referred to as columnar or convoluted cells)
3) The cytoplasm is coarsely granular
524
*What should be done to RTE cells and why should this be done?
They should be closely examined for the presence of a nucleus, as a nucleus would not be present in a cast
525
What are the characteristics of a PCT (/ columnar proximal convoluted tubule cell)?
1) This have granules
2) This have attached fat globules
3) This have nucleus
4) This is a fine cell that has absorbed fat globules and could be easily mistaken for a granular or fatty cast
526
What are the characteristics of cells from distal convoluted tubule (DCT)?
1) These are smaller than those those from the PCT
2) These are round or oval
3) These can be mistaken for WBCs and spherical transitional epithelial cells
527
What aids in the differentiation between cells from DCT and cells from spherical transitional cells?
Observation of the eccentrically placed round nucleus
528
What is the characteristic of collecting duct RTE cells?
These are cuboidal (these are never round)
529
What are the characteristics that differentiates collecting duct RTE cells from spherical and polyhedral transitional cells?
1) These have eccentrically placed nucleus
| 2) These have presence of at least 1 straight edge
530
RTE cells are often present as a result of what condition / disorder?
Tissue destruction (necrosis)
531
Since RTE cells are often present as a result of tissue destruction (necrosis), what is the characteristic of RTE cells (w/c is correlated w/ the given condition / disorder)?
The nucleus is not easily visible in unstained sediment
532
What are renal fragments?
These are cells from the collecting duct that appear in grps of 3 or more
533
What is the characteristic of renal fragments?
These are frequently seen as large sheets of cells
534
True or False
PCT and DCT cells are seen in large sheets of cells
False, because PCT and DCT cells are not seen in large sheets of cells
535
What is the magnification (/ objective) used to identify and enumerate RTE cells?
High-power magnification (/ hpo / hpf)
536
How are RTE cells reported?
These may be reported as (depending on lab protocol):
1) Rare
2) Few
3) Moderate
4) Many
Or these can be reported as the actual # per hpf
537
Is classification of RTE cells as to site of origin considered a part of the routine sediment analysis?
No, because the classification of RTE cells as to site of origin is not considered a part of the routine sediment analysis
538
Classification of RTE cells as to site of origin often requires what?
Special staining techniques
539
The presence of more than 2 RTE cells/hpf indicates what condition / disorder?
Tubular injury
540
What should be done to sxs having more than 2 RTE cells/hpf?
These sxs should be referred for cytologic urine testing
541
Among all the types of epithelial cells, what type is the most clinically significant?
RTE cells
542
The presence of increased amts of RTE cells is indicative of what condition / disorder?
Necrosis of renal tubules (w/ the possibility of affecting overall renal fxn)
543
What are the conditions that produce tubular necrosis (as a part of clinical significance of RTE cells)?
1) Exposure to heavy metals
2) Drug-induced toxicity
3) Hgb toxicity
4) Myoglobin toxicity
5) Viral infections
a. Hepatitis B
6) Pyelonephritis
7) Allergic rxns
8) Malignant infiltrations
9) Salicylate poisoning
10) Acute allogenic transplant rejection
544
RTE cells may also be seen as 2ndary effects of what conditions / disorders (as a part of clinical significance of RTE cells)?
Glomerular disorders
545
Renal fragments are an indication of what condition / disorder (as a part of clinical significance of RTE cells)?
Severe tubular injury w/ basement membrane disruption
546
What cells are particularly noticeable in cases of salicylate poisoning (as a part of clinical significance of RTE cells)?
Single cuboidal cells
547
Because 1 of the fxns of RTE cells is reabsorption of the glomerular filtrate, it is not unusual for them to contain what?
It is not unusual for them to contain substances from the filtrate
548
RTE cells absorb bili present in the filtrate as the result of what condition / disorder (as a part of clinical significance of RTE cells)?
Liver damage
549
At what condition / disorder does RTE cells absorb bili present in the filtrate (as a part of clinical significance of RTE cells)?
Viral hepatitis (whereas these cells appear as deep yellow color)
550
What is the action of RTE cells in the hgb w/c is present in the filtrate (as a part of clinical significance of RTE cells)?
These absorbed hgb (w/c is present in the filtrate) and convert it to hemosiderin
551
Due to the action of RTE cells to hgb (present in the filtrate), what may be the characteristic of RTE cells following episodes of hgburia (transfusion rxns, paroxysmal nocturnal hemoglobinuria [PNH]), etc.)?
The RTE cells may contain the characteristic yellow-brown hemosiderin granules
552
The granules (specifically the yellow-brown hemosiderin granules contained in RTE cells) may also be seen where?
These may also be seen free-floating in the urine sediment
553
How is confirmation of the presence of hemosiderin performed?
Via staining the urine sediment w/ Prussian blue
554
What is the color stained by iron-containing hemosiderin granules (when confirmation for the presence of hemosiderin is done | as a part of clinical significance of RTE cells)?
These stain blue
555
Answer the ff questions w/ regards to the given epithelial cell:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given epithelial cell: Squamous cells
1) a. Largest cells in the sediment
b. Has abundant, irregular cytoplasm
c. Has a prominent nuclei
2) a. Rarely encountered
b. Folded cells may resemble casts
3) Per lpf
a. Rare
b. Few
c. Moderate
d. Many
4) Clarity
556
* Answer the ff questions w/ regards to the given epithelial cell:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given epithelial cell: Transitional cells
1) a. Spherical
b. Polyhedral
c. Caudate (w/ centrally located nucleus)
2) Spherical forms (resemble RTE cells)
3) Per hpf
a. Rare
b. Few
c. Moderate
d. Many
4) a. Clarity
b. Blood (if malignancy-associated)
557
* Answer the ff questions w/ regards to the given epithelial cell:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given epithelial cell: RTE cells
1) a. Rectangular
b. Columnar
c. Round
d. Oval
e. Cuboidal (w/ an eccentric nucleus possibly bilirubin-stained or hemosiderin-laiden)
2) a. Spherical transitional cells
b. Granular casts
3) Average number per 10 hpfs
4) a. LE and nitrite (pyelonephritis)
b. Color
c. Clarity
d. Protein
e. Bilirubin (hepatitis)
f. Blood
558
Answer the ff questions w/ regards to the given epithelial cell:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given epithelial cell: Oval fat bodies
1) Highly refractile RTE cells
2) Confirm w/:
a. Fat stains
b. Polarized microscopy
3) Average number per hpf
4) a. Clarity
b. Blood
c. Protein
d. Free fat droplets / fatty casts
559
What is the action of RTE cells?
These absorb lipids that are present in the glomerular filtrate
560
What are the characteristics of oval fat bodies?
Since RTE cells absorb lipids that are present in the glomerular filtrate, these then:
1) Appear refractile
2) The nucleus may be more difficult to observe
561
What are oval fat bodies?
These are lipid-containing RTE cells
562
Oval fat bodies are usually seen in conjunction w/ what?
Free-floating fat droplets
563
How is identification of oval fat bodies confirmed?
1) Via staining the urine sediment w/ fat stains such as:
a. Sudan III fat
b. Or Oil Red O
2) Via examining the sediment using polarized microscopy
564
What are the components whereas droplets (/ oval fat bodies) are composed of?
1) TAG
2) Neutral fats
3) Chole
565
What are the components that fat stains stain?
1) TAG
| 2) Neutral fats
566
What is the color produced when fat stains stain TAG and neutral fats?
Orange-red droplets
567
Examination of the urine sediment using polarized light results in what?
Appearance of characteristic Maltese cross formations (in droplets containing chole)
568
What should be done to urine sediments (-) for fat after staining?
These still should be checked using polarized light in case only chole is present
569
What should be done if urine sediments are (-) under polarized light?
Staining should be performed in these urine sediments
570
How are oval fat bodies reported?
Average number/hpf
571
True or False
Free-floating fat droplets also stain or polarize depending on their composition
True
572
When may free-floating fat droplets observed?
They may be observed floating on top of the sx
573
True or False
Care should be taken not to confuse the droplets w/ starch and crystal particles that also polarize
True
574
When must sxs contaminated by vaginal preparations and lubricants used in sx collection be considered?
When only free-floating fat droplets are present
575
Lipiduria is most frequently associated w/ what condition / disorder?
Damage to the glomerulus (w/c is caused by nephrotic syndrome)
576
Aside from damage to the glomerulus (w/c is the condition / disorder where lipiduria is most frequently associated), what are the other conditions / disorders where lipiduria is also seen?
1) Severe tubular necrosis
2) DM
3) Trauma cases (that cause release of bone marrow fat from the long bones)
577
True or False
In lipid-storage diseases, large fat-laiden histiocytes may also be present
True
578
How can large fat-laiden histiocytes be differentiated from oval fat bodies?
These can be differentiated from oval fat bodies by their large size
579
In cases of acute tubular necrosis, what are the cells (and its characteristics) that may be seen along w/ normal renal tubular cells and oval fat bodies?
RTE cells (containing large, nonlipid-filled vacuoles)
580
What are bubble cells?
These are RTE cells containing large, nonlipid-filled vacuoles
581
Why do bubble cells appear?
To represent injured cells in w/c the endoplasmic reticulum has dilated prior to cell death
582
Are bacteria normally present in urine?
No
583
Since bacteria are not normally present in urine, when are few bacteria usually present in urine sxs?
When sxs are collected under sterile conditions
584
Provide an ex of method for collecting urine sxs under sterile conditions
Catheterization
585
Since a few bacteria are usually present in urine sxs if these are collected under sterile conditions, what are the causes of presence of few bacteria in the sxs?
1) Vaginal contamination
2) Urethral contamination
3) External genitalia contamination
4) Collection-container contamination
586
What are the characteristics of contaminant bacteria (w/c are usually present if the sxs are collected under sterile conditions)?
1) These multiply rapidly
2) They may produce a (+) nitrite test result
3) They also frequently result in a pH above 8 (w/c indicates an unacceptable sx)
587
At what type of sx does contaminant bacteria multiply rapidly?
In sxs that remain at room temp for extended periods
588
Are contaminant bacteria clinically significant?
No, they are of no clinical significance
589
What are the forms of bacteria (whereas they can be present)?
They can be present in the form of:
1) Cocci (spherical)
2) / Bacilli (rods)
590
What is the characteristic of bacteria?
They have a small size
591
Since bacteria are small, what objective must be used when reporting bacteria?
High-power magnification (/ hpo / hpf)
592
How are bacteria reported?
They are reported as (/ hpf):
1) Few
2) Moderate
3) Many
593
How to consider bacteria as significant for UTI?
Bacteria should be accompanied by WBCs
594
True or False
All labs report bacteria only when observed in fresh sxs in conjunction w/ WBCs
False, because some labs report bacteria only when observed in fresh sxs in conjunction w/ WBCs
595
The presence of motile organisms in a drop of fresh urine collected under sterile conditions correlates well w/ what?
(+) urine culture
596
What is the use / aid of observing bacteria for motility?
It is also useful in differentiating them from similarly appearing amorphous phosphates and urates
597
The use of phase microscopy aids in what?
In the visualization of bacteria
598
What is the conditions / disorders indicated by the presence of bacteria?
Either:
1) Lower UTI
2) / Upper UTI
599
What should be done to sxs containing increased bacteria and leukocytes?
These are routinely followed up w/ a sx for quantitative urine culture
600
What is the family of bacteria that is most frequently associated w/ UTI?
Enterobacteriaceae
601
What are Enterobacteriaceae (/ what is its morphology)?
These are referred to as gram-(-) rods
602
Aside from Enterobacteriaceae as being most frequently associated w/ UTI, what are the other 2 families of bacteria that are also capable of causing UTI?
1) Staphylococcus
| 2) Enterococcus
603
What are Staphylococcus (/ what is its morphology)?
Cocci-shaped
604
Can the actual bacteria producing an UTI be identified w/ microscopic examination?
No
605
What are the characteristics of yeast?
1) Small
2) Refractile
3) Oval structures
4) May / may not contain a bud
5) Appear as branched, mycelial forms (in severe infections)
606
How are yeast cells reported?
These are reported as (/ hpf):
1) Rare
2) Few
3) Moderate
4) Many
607
True or False
Differentiation between yeast cells and RBCs is not difficult
False, because the differentiation between yeast cells and RBCs can sometimes be difficult
608
In terms of differentiation between yeast cells and RBCs (w/c can sometimes be difficult), what should be done (w/c is helpful)?
Careful observation for budding yeast cells
609
What is the sp. of yeast cells that are primarily seen in the urine of diabetic pts, immunocompromised pts, and women w/ vaginal moniliasis?
Candida albicans
610
What is the urine that provides an ideal medium for the growth of yeast?
Acidic, glucose-containing urine of pts w/ diabetes
611
True or False
A small amt of yeast entering a sx as a contaminant multiplies rapidly if the sx is not examined while fresh
True
612
How to say that it is a true yeast infection?
A true yeast infection should be accompanied by the presence of WBCs
613
What is the most frequent parasite encountered in the urine?
Trichomonas vaginalis
614
What are the characteristics of Trichomonas trophozoite?
1) Pear-shaped flagellate
| 2) Has undulating membrane
615
Where is the Trichomonas trophozoite easily identified?
In wet preparations (of the urine sediment)
616
How is the Trichomonas trophozoite easily identified in wet preparations of the urine sediment?
By its rapid darting movement in the microscopic field
617
How is Trichomonas usually reported?
It is usually reported as (/hpf):
1) Rare
2) Few
3) Moderate
4) Many
618
When Trichomonas is not moving, it is more difficult to identify and it may resemble what?
1) WBC
2) Transitional
3) / RTE cell
619
What should be done to enhance the visualization of flagella or undulating membrane (of T. vag)?
Phase microscopy
620
What is T. vag?
It is a sexually transmitted pathogen associated primarily w/ vaginal inflammation
621
True or False
The infection (due to T. vag) of the male urethra and prostate is symptomatic
False, because the infection (due to T. vag) of the male urethra and prostate is asymptomatic
622
True or False
Males are often symptomatic carriers (in terms of T. vag infection)
False, because males are often asymptomatic carriers (in terms of T. vag infection)
623
Does the ova of the bladder parasite Schistosoma haematobium appear in the urine?
Yes
624
Schistosoma haematobium is seldom seen in what country?
U.S.
625
Schistosoma haematobium has been associated w/ what condition / disorder in other countries?
CA
626
Fecal contamination of a urine sx can also result in the presence of what?
Presence of ova from intestinal parasites in the urine sediment
627
What is the most common contaminant (w/c is present due to fecal contamination of urine) in the urine?
Ova from pinworm Enterobius vermicularis
628
What are the characteristics of spermatozoa (that makes them easily identified in the urine sediment)?
1) Has oval, slightly tapered heads
| 2) Long, flagella-like tails
629
Is urine toxic to spermatozoa?
Yes
630
True or False
Since urine is toxic to spermatozoa, they rarely exhibit the motility observed when examining a semen sx
True
631
When are spermatozoa occasionally found?
These are occasionally found in the urine of both men and women ff:
1) Sexual intercourse
2) Masturbation
3) / Nocturnal emission
632
Is the presence of spermatozoa in urine sxs clinically significant?
They are rarely of clinical significance except in cases of:
1) Male infertility
2) / Retrograde ejaculation
633
What is retrograde ejaculation?
It is the condition where sperm is expelled into the bladder instead of the urethra
634
In the chemical examination, what may be seen when increased amts of semen are present?
A (+) rgnt strip for protein
635
True or False
Lab protocols vary w/ regard to reporting or not reporting the presence of spermatozoa in a urine sx
True
636
True or False
Labs not reporting the presence of spermatozoa cite the lack of clinical significance and possible legal consequences
True
637
True or False
Labs supporting the reporting of spermatozoa cite the possible clinical significance and the minimal possibility of legal consequences
True
638
What is mucus?
It is a protein material produced by the glands and epithelial cells of the lower genitourinary tract and the RTE cells
639
What is the major constituent of mucus (as shown by immunologic analysis)?
Uromodulin
640
What is uromodulin?
It is a glycoprotein excreted by the RTE cells of the DCTs and upper collecting ducts
641
What is required to be done when examining mucus (via the use of bright-field microscopy)?
Examine it under subdued light
642
True or False
Care must be taken not to confuse clumps of mucus w/ hyaline casts
True
643
How can the differentiation between mucus and hyaline casts be made?
It is usually made by observing the irregular appearance of the mucous threads
644
How are mucus threads reported?
These are reported as (/hpf):
1) Rare
2) Few
3) Moderate
4) Many
645
At what gender are mucus threads more frequently present?
Female (in urine sxs)
646
Is presence of mucus threads in either female / male urine clinically significant?
No, it has no clinical significance
647
Answer the ff questions w/ regards to the given miscellaneous structure:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given miscellaneous structure: Bacteria
1) a. Small spherical structure
b. Rod-shaped structure
2) a, Amorphous phosphates
b. Amorphous urates
3) /hpf
a. Few
b. Moderate
c. Many
- > presence of WBCs may be required
4) a. pH
b. Nitrite
c. LE
d. WBCs
648
Answer the ff questions w/ regards to the given miscellaneous structure:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given miscellaneous structure: Yeast
1) a. Small
b. Oval
c. Refractile structures (w/ buds and/or mycelia)
2) RBCs
3) /hpf
a. Rare
b. Few
c. Moderate
d. Many
- > presence of WBCs may be required
4) a. Glucose
b. LE
c. WBCs
649
Answer the ff questions w/ regards to the given miscellaneous structure:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given miscellaneous structure: Trichomonas
1) a. Pear-shaped
b. Motile
c. Flagellated
2) a. WBCs
b. RTE cells
3) /hpf
a. Rare
b. Few
c. Moderate
d. Many
4) a. LE
b. WBCs
650
Answer the ff questions w/ regards to the given miscellaneous structure:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given miscellaneous structure: Spermatozoa
1) a. Tapered oval head
b. Long, thin tail
2) None
3) Present (based on lab protocol)
4) Protein
651
Answer the ff questions w/ regards to the given miscellaneous structure:
1) What is/are the appearance/s?
2) What is/are the source/s of identification error?
3) What is the manner of reporting (/ how is reporting done)?
4) What are the other aspect/s where complete UA correlations can be done?
Given miscellaneous structure: Mucus
1) a. Single / clumped threads
b. Has low refractive index
2) Hyaline casts
3) /lpf
a. Rare
b. Few
c. Moderate
d. Many
4) None
652
What are the only elements found in the urinary sediment that are unique to the kidney?
Casts
653
Where are casts formed?
They are formed within the lumens of the DCTs and collecting ducts (providing a microscopic view of conditions within the nephron)
654
The shape of casts is representative of what?
Tubular lumen, w/ parallel sides and somewhat rounded ends, and they may contain additional elements present in the filtrate
655
What magnification / objective is used for the examination of the sediment for the detection of casts?
Lower power magnification (/ lpo / lpf)
656
What should be done (in terms of examination of casts) when the glass cover-slip method is used?
Low-power scanning should be performed along the edges of the cover slip
657
Does the cast matrix have a low refractive index?
Yes
658
Since the cast matrix have a low refractive index, what is essential to be done (in terms of examination of casts)?
Observation under subdued light
659
What is the characteristic of the cast matrix (w/c is similar to many other sediment constituents)?
It dissolves quickly in dilute, alkaline urine
660
What must be done once casts are detected (in terms of examination of casts)?
The casts must be further identified as to the composition using high-power magnification
661
How are casts reported?
Average number per 10 lpfs
662
What is the major constituent of casts?
Uromodulin
663
What are the other proteins present in the urinary filtrate?
1) Albumin
| 2) Immunoglobulins
664
Albumin and Igs are also incorporated where?
Into the cast matrix
665
True or False
Under normal conditions, uromodulin is excreted at a relatively constant rate
True
666
At what conditions does the rate of excretion (of uromodulin) appears to increase?
Under conditions of:
1) Stress
2) Exercise
667
What happens when conditions (such as stress and exercise) are present?
It may account for the transient appearance of hyaline casts
668
True or False
The protein gels more readily under conditions of urine-flow stasis, acidity, and the presence of Na and Ca
True
669
True or False
The extent of protein glycosylation is not impt (in relation w/ cast composition and formation)
False, because the extent of protein glycosylation is also impt (in relation w/ cast composition and formation)
670
At what types of urine is uromodulin protein found?
In both:
1) Normal urine
2) Abnormal urine
671
What is the major constituent of mucus?
Uromodulin
672
Is uromodulin detected by rgnt strip protein methods?
No
673
Since uromodulin is not detected by rgnt strip protein methods, the increased urinary protein frequently associated w/ the presence of casts is caused by what?
Underlying renal conditions
674
True or False
Scanning electron microscope (SEM) studies have provided a step-by-step analysis of the formation of the uromodulin protein matrix
True
675
What is the step-by-step analysis of the formation of the uromodulin protein matrix (as provided by SEM studies)?
1) Aggregation of uromodulin protein into individual protein fibrils attached to the RTE cells
2) Interweaving of protein fibrils to form a loose fibrillar network (urinary constituents may become enmeshed in the network at this time)
3) Further protein fibril interweaving to form a solid structure
4) Possible attachment of urinary constituents to the solid matrix
5) Detachment of protein fibrils from the epithelial cells
6) Excretion of the cast
676
True or False
As the cast forms, urinary flow within the tubule decreases as the lumen becomes blocked. The accompanying dehydration of the protein fibrils and internal tension may account for the wrinkled and convoluted appearance of older hyaline casts
True
677
The width of the cast depends on what?
Size of the tubule in w/c it is formed
678
Broad casts may result from what cases?
1) Tubular distension
2) / In the case of extreme urine stasis
3) From formation in the collecting ducts
679
Formation of casts at the junction of the ascending loop of Henle and the DCT may produce what?
Structures w/ a tapered end
680
What are cylindroids?
These are the structures (w/ a tapered end) that may be produced due to the formation of casts in the junction of the ascending loop of Henle and the DCT
681
Do cylindroids have the same clinical significance as casts?
No
682
What is cylinduria?
Presence of urinary casts
683
The appearance of a cast is also influenced by what factors?
1) By the materials present in the filtrate at the time of its formation
2) The length of time it remains in the tubule
684
What are the elements that are present in the tubular filtrate?
1) Cells
2) Bacteria
3) Granules
4) Pigments
5) Crystals
685
What may be the characteristics of any elements present in the tubular filtrate?
These may become embedded in / attached to the cast matrix
686
True or False
The types of casts found in the sediment represent different clinical conditions
True
687
What are the different types of casts?
1) Hyaline casts
2) RBC casts
3) WBC casts
4) Bacterial casts
5) Epithelial cell casts
6) Fatty casts
7) Mixed cellular casts
8) Granular casts
9) Waxy casts
10) Broad casts
688
What type of cast is the most frequently seen cast?
Hyaline type (/ hyaline cast)
689
What is the composition of hyaline casts?
These consists almost entirely of uromodulin
690
What values (in reporting) of hyaline casts is considered normal?
0 - 2 hyaline casts/lpf
691
*When is the finding (in reporting) of hyaline casts considered normal?
As in the finding of increased #s following:
1) Strenuous exercise
2) Dehydration
3) Heat exposure
4) Emotional stress
692
Pathologically, in what conditions / disorders are hyaline casts increased?
1) Acute glomerulonephritis
2) Pyelonephritis
3) Chronic renal disease
4) Congestive heart failure (CHF)
693
What are the characteristics of hyaline casts?
1) These appear colorless (in unstained sediments)
| 2) These have a refractive index similar to that of urine
694
True or False
Since hyaline casts have a refractive index similar to that of urine, they can be overlooked
True
695
When are hyaline casts overlooked (brought about by their characteristic)?
If sxs are not examined under subdued light
696
What is the color produced by Sternheimer-Malbin stain in hyaline casts?
Pink
697
How can increased visualization of hyaline casts be obtained?
Via phase microscopy
698
What is the description of the morphology of hyaline casts and what are its varying morphologies?
The morphology of hyaline casts is varied, consisting of:
1) Normal parallel sides and rounded cells
2) Cylindroid forms
3) Wrinkled / convoluted shapes
699
The morphology of hyaline casts being wrinkled or convoluted shapes indicate what?
Aging of the cast matrix
700
True or False
The presence of an occasional adhering cell / granule may not be observed (in examination of hyaline casts)
False, because the presence of an occasional adhering cell / granule may also be observed (in examination of hyaline casts)
701
Even if the presence of an occasional adhering cell / granule may also be observed (in examination of hyaline casts), does it change the classification of the cast?
No
702
The finding of RBCs in the urine indicates what?
It indicates the bleeding from an area within the GUT
703
What is the comparison between presence of RBCs and presence of RBC casts in the urine?
The presence of RBC casts is much more sp, showing bleeding within the nephron
If RBCs are present: indicative of bleeding from an area within the GUT
If RBC casts are present: indicative of bleeding within the nephron (much more sp. > presence of RBCs)
704
RBC casts are primarily associated w/ what condition / disorder?
Damage to the glomerulus (glomerulonephritis)
705
What is the action of glomerulonephritis (where RBC casts are primarily associated)?
It allows passage of the cells through the glomerular membrane
706
In association w/ glomerulonephritis, what can cause the formation of RBC casts?
Any damage to the nephron capillary structure
707
The RBC casts w/c are associated w/ glomerular damage are usually associated w/ what conditions / disorders?
1) Proteinuria
| 2) Dysmorphic erythrocytes
708
RBC casts have also been observed in whom?
In healthy individuals (following participation in strenuous contact sports)
709
What is the objective used to easily detect RBC casts?
Low power (/ lpo / lpf)
710
What is the characteristic of RBC casts w/c make them easily detected under low power?
They have an orange-red color
711
What are the characteristics of RBC casts?
1) They are more fragile than other casts
2) They may exists as fragments
3) / They have more irregular shape (as the result of tightly packed cells adhering to the protein matrix)
712
What magnification / objective should be used on determining that a cast matrix is present (of RBC casts) by a way of differentiating the structure (of RBC casts) from a clump of RBCs?
High-power magnification (/ hpo / hpf)
713
Because of the serious diagnostic implications of RBC casts, what must be done to the actual presence of RBCs?
The actual presence of RBCs must also be verified (to prevent the inaccurate reporting of nonexistent RBC casts)
714
True or False
It is highly improbable that RBC casts will be present in the absence of free standing RBCs and a (+) rgnt strip test for blood
True
715
What are the events that happen as an RBC cast ages?
1) Cell lysis begins
2) The cast develops a more homogenous appearance (but retains the characteristic orange-red color from the released hgb)
716
True or False
RBC casts may be distinguished as blood casts, indicating greater stasis of urine flow
True
717
True or False
Not all casts containing blood have the same clinical significance
False, because all casts containing blood have the same clinical significance
718
Since RBC casts may be distinguished as blood, however, all casts containing blood have the same clinical significance, is this (distinguishing) considered necessary?
No
719
*How are both types of casts (RBC casts and blood casts) reported?
Number of RBC casts/lpf
720
What are the casts that may be observed in the presence of massive hgburia / myoglobinuria (in connection w/ RBC casts)?
Homogenous orange-red / red-brown casts
721
Aside from homogenous orange-red / red-brown casts that may be observed in the presence of massive hgburia / myoglobinuria, what is the other casts that may also be present in this situation (in connection w/ RBC casts)?
Granular, dirty, brown casts (representing hgb degradation products such as methemoglobin)
722
The granular, dirty, brown casts are associated w/ what condition / disorder?
Acute tubular necrosis
723
What is the cause of acute tubular necrosis (w/c is associated w/ granular, dirty, brown casts)?
It is often caused by the toxic effects of massive hgburia that can lead to renal failure
724
The dirty, brown casts must be present in conjunction w/ other pathologic findings such as what?
1) RTE cells
| 2) (+) rgnt strip test for blood
725
The appearance of WBC casts in the urine signifies what conditions / disorders (in connection w/ WBC casts)?
1) Infection
| 2) / Inflammation within the nephron
726
WBC casts are most frequently associated w/ what condition / disorder?
Pyelonephritis
727
WBC casts are a primary marker for distinguishing what condition / disorder?
These are a primary marker for distinguishing pyelonephritis from cystitis
728
What is the location that pyelonephritis affect?
Upper UTI
729
What is the location that cystitis affect?
Lower UTI
730
Are WBC casts also present in nonbacterial inflammations (such as acute interstitial nephritis)?
Yes
731
Do WBC casts may accompany RBC casts in glomerulonephritis?
Yes
732
What is the magnification / objective where WBC casts are visible?
Low-power magnification (/ lpo / lpf)
733
What is the magnification / objective used to positively identify WBC casts?
High power (/ hpo / hpf)
734
WBC casts are most frequently composed of what?
Neutrophils
735
Since WBC casts are most frequently composed of neutrophils, what may be their characteristics?
They may appear granular (unless disintegration has occurred, multilobed nuclei will be present)
736
What may be necessary to demonstrate the characteristic nuclei of WBC casts?
Supravital staining
737
What is the aid of supravital staining (in connection w/ WBC casts)?
It is particularly helpful for differentiating WBC casts from RTE casts
738
True or False
Observation of free WBCs in the sediment is not essential
False, because observation of free WBCs in the sediment is also essential
739
What are the characteristics of bacteria (in connection w/ certain conditions / disorders)?
1) They are present in cases of pyelonephritis
| 2) But they are not present w/ acute interstitial nephritis
740
True or False
Eosinophil casts may be present in appropriately stained sxs (via the use of Hansel and Wright's stains | in connection w/ characteristics of bacteria in certain conditions / disorders)
True
741
What may be the characteristic of casts that are tightly packed w/ WBCs?
They may have irregular borders
742
What should be done to casts that are tightly packed w/ WBCs?
They should be carefully examined to determine that a cast matrix is present
743
Do WBCs frequently form clumps?
Yes
744
Do WBCs that form clumps have the same significance as casts?
Yes
745
Bacterial casts containing bacilli both within and bound to the protein matrix are seen in what condition / disorder?
Pyelonephritis
746
What may be the characteristic of bacterial casts seen in pyelonephritis?
They may be pure bacterial casts / mixed w/ WBCs
747
True or False
Identification of bacterial casts can be difficult
True
748
Why is the identification of bacterial casts can be difficult?
Because packed casts packed w/ bacteria can resemble granular casts
749
When should the presence of bacterial casts be considered?
When WBC casts and many free WBCs and bacteria are seen in the sediment
750
How is the confirmation of bacterial casts best made?
Via performing a Gram stain on the dried / cytocentrifuged sediment
751
Casts containing RTE cells represent what condition / disorder (in connection w/ epithelial cell casts)?
Presence of advanced tubular destruction (producing urinary stasis along w/ disruption of the tubular linings)
752
Similar to RTE cells, casts containing RTE cells are associated w/ what conditions / disorders (in connection w/ epithelial cell casts)?
1) Heavy metal toxicity
2) Chemical toxicity
3) / Drug-induced toxicity
4) Viral infections
5) Allograft rejection
753
True or False
Casts containing RTE cells also accompany RBC casts in cases of pyelonephritis (in connection w/ epithelial cell casts)
False, because casts containing RTE cells also accompany WBC casts in cases of pyelonephritis (in connection w/ epithelial cell casts)
754
True or False
The fibrils of uromodulin protein that make up the cast matrix remain attached to the RTE cells that produce them (in connection w/ epithelial cell casts)
True
755
True or False
Since the fibrils of uromodulin protein that make up the cast matrix remain attached to the RTE cells that produce them, the observation of an occasional tubular cell attached to a hyaline cast can be expected
True
756
What happens if tubular damage is present (in connection w/ epithelial cell casts)?
Some cells may be incorporated into the cast matrix (but the majority will be very noticeably attached to the cast surface)
757
Owing to the formation of casts in the DCT, what are the characteristics of the cells that are visible on the cast matrix?
These are cells that are:
1) Smaller
2) Round
3) Oval
4) Also these may be difficult to differentiate from WBCs (particularly if degeneration has occurred)
758
What can be done to enhance the nuclear detail (of the casts that are formed in the DCT) needed for identification (in connection w/ epithelial cell casts)?
1) Staining
| 2) Use of phase microscopy
759
True or False
Fragments of epithelial tissue may also be attached to the cast matrix (in connection w/ epithelial cell casts)
True
760
At what condition / disorder are bilirubin-stained RTE cells seen (in connection w/ epithelial cell casts)?
Hepatitis
761
Fatty casts are seen in conjunction w/ what?
1) Oval fat bodies
2) Free fat droplets
In disorders causing lipiduria
762
Fatty casts are most frequently associated w/ what condition / disorder?
Nephrotic syndrome
763
Aside from nephrotic syndrome (where fatty casts are most frequently associated), fatty casts are also seen in what conditions / disorders?
1) Toxic tubular necrosis
2) DM
3) Crush injuries
764
What is the characteristic of fatty casts?
These are highly refractile (under bright-field microscopy)
765
What is the characteristic of the cast matrix of fatty casts?
1) It may contain few / many fat droplets
| 2) It may also contain intact oval fat bodies (w/c may be attached to the matrix)
766
What should be used for confirmation of fatty casts?
1) Using polarized microscopy
2) Using fat stains
a. Sudan III
b. Oil Red O
767
What does chole demonstrate under polarized light (in connection w/ fatty casts)?
Characteristic Maltese cross formations
768
What is the rxn of TAG and neutral fats w/ fat stains (in connection w/ fatty casts)?
These stain orange
769
What is the characteristic of fats (in connection w/ fatty casts)?
These do not stain w/ Sternheimer-Malbin stains
770
True or False
Considering that a variety of cells may be present in the urinary filtrate, observing casts containing multiple cell types is not uncommon (in connection w/ mixed cellular casts)
True
771
What are the mixed cellular casts are most frequently encountered in glomerulonephritis?
1) RBC casts
| 2) WBC casts
772
What are the mixed cellular casts are most frequently encountered in pyelonephritis?
1) WBC casts
2) & RTE cell casts
3) / WBC casts
4) & Bacterial casts
773
True or False
The presence of mixed elements in a cast does not make identification difficult (in connection w/ mixed cellular casts)
False, because the presence of mixed elements in a cast may make identification more difficult (in connection w/ mixed cellular casts)
774
What aids in the identification of mixed elements (in connection w/ mixed cellular casts)?
1) Staining
| 2) / Phase microscopy
775
What is the phenomenon that should also present when mixed casts are present?
There should also be homogenous casts of at least 1 of the cell types
776
What is the aid of homogenous casts of at least 1 of the cell types (in connection w/ mixed cellular casts)?
They will be the primary diagnostic marker
777
Provide an ex of the situation whereas when mixed casts are present, there should also be homogenous casts of at least 1 of the cell types
In glomerulonephritis, the predominant casts will be RBC, and in pyelonephritis, the predominant casts will be WBC
778
True or False
Bacteria are often incorporated into WBC casts and provide little additional diagnostic significance (in connection w/ mixed cellular casts)
True
779
True or False
It is okay not to follow lab protocol in the reporting of mixed cellular casts
False, because lab protocol should be followed in reporting of mixed cellular casts
780
Where are coarsely and finely granular casts seen?
In the urinary sediment
781
Are coarsely and finely granular casts pathologically significant (in connection w/ granular casts)?
These may be of pathologic / nonpathologic significance
782
True or False
It is considered necessary to distinguish between coarsely and finely granular casts (in connection w/ granular casts)
False, because it is not considered necessary to distinguish between coarsely and finely granular casts (in connection w/ granular casts)
783
What is the origin of the granules (of granular casts) in nonpathologic conditions?
From the lysosomes excreted by RTE cells during normal metabolism
784
True or False
It is unusual to see hyaline casts containing 1 / 2 of these granules (granules of granular casts [of nonpathologic conditions] | in connection w/ granular casts)
False, because it is not unusual to see hyaline casts containing 1 / 2 of these granules (granules of granular casts [of nonpathologic conditions] | in connection w/ granular casts)
785
Increased cellular metabolism occurring during periods of strenuous exercise accounts for what (in connection w/ granular casts)?
It accounts for the transient increase of granular casts that accompany the increased hyaline casts
786
In disease states, the granules (of granular casts) may represent what?
These may represent disintegration of cellular casts and tubule cells / protein aggregates filtered by the glomerulus
787
What do SEM studies have confirmed (in connection w/ granular casts)?
These confirmed that granular casts seen in conjunction w/ WBC casts containing WBC granules of varying sizes
788
True or False
Urinary stasis allowing the casts to remain in the tubules must be present for granules to result from disintegration of cellular casts (in connection w/ granular casts)
True
789
What is the characteristic of granular casts w/c occur as a result of cellular disintegration?
These may contain an occasional recognizable cell
790
At what magnification are granular casts easily visualized?
Low-power microscopy (/ lpo / lpf)
791
What magnification / objective should be used when performing the final identification of determining the presence of a cast matrix (of granular casts)?
High power (/ hpo / hpf)
792
What are the artifacts that must be differentiated w/ granular casts?
1) Clumps of small crystals
| 2) Fecal debris
793
What is the characteristic of artifacts (that must be differentiated w/ granular casts)?
These may occur in shapes resembling casts
794
True or False
Columnar RTE cells may also resemble granular casts
True
795
What may be required to be done (in terms of differentiation of columnar RTE cells w/ granular casts)?
Staining for nuclear detail
796
What are the events that happen to granular casts when they remain in the tubules for extended periods?
1) The granules further disintegrate
2) The cast matrix develops a waxy appearance
3) The structure becomes more rigid
4) The ends of the casts may appear jagged / broken
5) The diameter becomes broader
797
Waxy casts are representative of what condition / disorder?
Extreme urine stasis (indicating chronic renal failure)
798
True or False
Waxy casts are usually seen in conjunction w/ other types of casts associated w/ the condition that has caused the renal failure
True
799
True or False
The brittle, highly refractive cast matrix from w/c these casts derive their name is believed to be caused by degeneration of the hyaline cast matrix and any cellular elements / granules contained in the matrix
True
800
What is more easily visualized, waxy casts or hyaline casts and why?
Waxy casts, because of their higher refractive index
801
What is the characteristic of waxy casts as a result of the brittle consistency of the cast matrix?
They often appear fragmented w/ jagged ends and have notches in their sides
802
What is the rxn of waxy casts w/ supravital stains?
These stain a homogenous, dark pink
803
Broad casts are often referred to as what?
Renal failure casts
804
Broad casts like waxy casts represent what (in connection w/ broad casts)?
Extreme urine stasis
805
As a mold of the DCTs, the presence of broad casts indicates what (in connection w/ broad casts)?
Destruction (widening) of the tubular walls
806
True or False
When the flow of urine to the larger collecting ducts becomes severely compromised, casts form in this area and appear broad (in connection w/ broad casts)
True
807
True or False
All casts may or may not occur in the broad form (in connection w/ broad casts)
False, because all casts may occur in the broad form
808
Since all types of casts may occur in the broad form, considering the accompanying urinary stasis, what is the most commonly seen broad casts (in connection w/ broad casts)?
1) Granular casts
| 2) Waxy casts
809
Presence of bile-stained broad, waxy casts are seen as the result of what condition / disorder (in connection w/ broad casts)?
Tubular necrosis
810
What is the cause of tubular necrosis (whereas bile-stained broad, waxy casts are seen in this condition / disorder | in connection w/ broad casts)?
Viral hepatitis
811
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: Hyaline cast
1) a. Colorless
b. Homogenous matrix
2) a. Mucus
b. Fibers
c. Hair
d. Increased lighting
3) Average number/lpf
4) a. Protein
b. Blood (exercise)
c. Color (exercise)
5) a. Glomerulonephritis
b. Pyelonephritis
c. Chronic renal disease
d. CHF
e. Stress
f. Exercise
812
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: RBC cast
1) a. Orange-red color
b. Cast matrix containing RBCs
2) RBC clumps
3) Average number/lpf
4) a. RBCs
b. Blood
c. Protein
5) a. Glomerulonephritis
b. Strenuous exercise
813
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: WBC cast
1) Cast matrix containing WBCs
2) WBC clumps
3) Average number/lpf
4) a. WBCs
b. Protein
c. LE
5) a. Pyelonephritis
b. Acute interstitial nephritis
814
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: Bacterial cast
1) Bacilli bound to protein matrix
2) Granular casts
3) Average number/lpf
4) a. WBC casts (pyelonephritis)
b. WBCs
c. LE
d. Nitrite
e. Protein
f. Bacteria
5) Pyelonephritis
815
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: Epithelial cell
1) RTE cells attached to protein matrix
2) WBC cast
3) Average number/lpf
4) a. Protein
b. RTE cells
5) Renal tubular damage
816
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: Granular cast
1) Coarse and fine granules in a cast matrix
2) a. Clumps of small crystals
b. Columnar RTE cells
3) Average number/lpf
4) a. Protein
b. Cellular casts
c. RBCs
d. WBCs
5) a. Glomerulonephritis
b. Pyelonephritis
c. Stress
d. Exercise
817
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: Waxy cast
1) a. Highly refractile
b. W/ jagged ends and notches
2) a. Fibers
b. Fecal material
3) Protein
4) a. Cellular casts
b. Granular casts
c. WBCs
d. RBCs
5) a. Stasis of urine flow
b. Chronic renal failure
818
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: Fatty cast
1) Fat droplets and oval fat bodies (attached to protein matrix)
2) Fecal debris
3) Average number/lpf
4) a. Protein
b. Free fat droplets
c. Oval fat bodies
5) a. Nephrotic syndrome
b. Toxic tubular necrosis
c. DM
d. Crush injuries
819
Answer the ff questions w/ regards to the given urine cast:
1) What is/are the appearance/s?
2) What is/are the source/s of error?
3) What is the manner of reporting?
4) What is/are the test/s of UA where it can be correlated?
5) What is/are the clinical significance?
Given urine cast: Broad cast
1) Wider than normal cast matrix
2) a. Fecal material
b. Fibers
3) Average number/lpf
4) a. Protein
b. WBCs
c. RBCs
d. Granular casts
e. Waxy casts
5) a. Extreme urine stasis
b. Renal failure
820
What are the characteristics of crystals that are frequently found in the urine?
1) These are rarely of clinical significance
| 2) They may appear as true geometrically formed structures / as amorphous material
821
What is the primary reason for the detection of urinary crystals?
To detect the presence of the relatively few abnormal types that may represent such disorders
822
What can be the disorders that may be represented by relatively few abnormal types of crystals?
1) Liver disease
2) Inborn errors of metabolism
3) Renal damage (w/c is caused by crystallization of medications compounds within the tubules)
823
How are crystals usually reported?
These are usually reported as (/hpf):
1) Rare
2) Few
3) Moderate
4) Many
824
How are abnormal crystals reported?
These may be averaged and reported/lpf
825
How are crystals formed?
These are formed by the precipitation of urine solutes
826
What are the urine solutes that precipitate w/c causes the formation of crystals?
1) Inorganic salts
2) Organic compounds
3) Medications (iatrogenic compounds)
827
Precipitation is subject to changes in what?
1) Temp
2) Solute conc.
3) pH
Whereas these factors affect solubility
828
What is the characteristic of solutes?
They precipitate more readily at low temps
829
Due to the characteristic of solutes, in what type of sxs does majority of crystal formation take place?
Majority of crystal formation takes place in:
1) Sxs that have remained at room temp
2) Sxs that have been refrigerated prior to testing
830
What is the characteristic of refrigerated sxs?
They are extremely abundant in crystals
831
Since refrigerated sxs are extremely abundant in refrigerated sxs, what is its effect to microscopic examination and why?
These often present problems because they obscure clinically significant sediment constituents
832
True or False
As the conc. of urinary solutes increases, their ability to remain in solution increases, resulting in crystal formation
False, because as the conc. of urinary solutes increases, their ability to remain in solution decreases, resulting in crystal formation
833
The presence of crystals in freshly voided urine is most frequently associated w/ what type of sxs?
W/ concentrated (high SG) sxs
834
What is the factor that is a valuable aid in the identification of crystals and why?
pH of the sx, because this determines the type of chemicals precipitated
835
In general, at what pH does organic and iatrogenic compounds crystallize more easily?
In acidic pH
836
In general, at what pH does inorganic salts less soluble?
In neutral and alkaline solutions
837
At what pH does calcium oxalate precipitate (w/c is an exception to the general characteristics of organic, iatrogenic compounds, and inorganic salts)?
In both acidic and neutral urine
838
What is the characteristic of the most commonly seen crystals?
They have very characteristic shapes and colors
839
Even if the most commonly seen crystals have very characteristic shapes and colors, what can occur and what is its effect?
Variations do occur and can present identification problems, particularly when they resemble abnormal crystals
840
How are crystals classified?
They are classified as:
1) Normal
2) Abnormal
3) To their appearance
a. In acidic urine
b. / in alkaline urine
841
At what pH does all abnormal crystals found?
In acidic urine
842
Aside from pH (as an aid in crystal identification), what are the other additional things that can aid in crystal identification?
1) Use of polarized microscopy
| 2) Solubility characteristics of the crystals
843
The geometric shape of a crystal determines what?
The birefringence of the crystal
844
Are crystals able to polarize light?
Yes
845
True or False
Although the size of a particular crystal may vary (slower crystallization produces larger crystals), the basic structure remains the same. Therefore, polarization characteristics for a particular crystal are constant for identification purposes
True
846
Since changes in temp and pH contribute to crystal formation, what happens if these changes are reversed?
It can cause crystals to dissolve
847
Can the solubility characteristics of crystals used to aid in identification (of crystals)?
Yes
848
How does amorphous urates frequently formed?
They are frequently formed in refrigerated sxs
849
What is the effect of the formation of amorphous urates?
It obscure sediments
850
How can amorphous urates dissolve?
They may dissolve if the sx is warmed
851
How does amorphous phosphates dissolve?
They require acetic acid to dissolve
852
Is the use of acetic acid to dissolve amorphous phosphates practical? Why or why not?
No, because formed elements (such as RBCs) will also be destroyed
853
What should be done when solubility characteristics are needed for identification (of crystals)?
The sediment should be aliquoted to prevent destruction of other elements
854
What are the most common crystals seen in acidic urine?
Urates, consisting of:
1) Amorphous urates
2) Uric acid
3) Acid urates
4) Sodium urates
855
What is the characteristic of most urate crystals?
Most urate crystals appear yellow to reddish brown
856
What is the characteristic of most urate crystals?
They are the only normal crystals found in acidic urine that appear colored
857
What are the characteristics of amorphous urates (microscopically)?
1) They appear as yellow-brown granules
2) They may occur in clumps (resembling granular casts)
3) They are attached to other sediment structures
858
At what type of sx are amorphous urates frequently encountered?
In sxs that have been refrigerated
859
What is the action of amorphous urates in refrigerated sxs?
They produce a very characteristic pink sediment
860
What is the cause of the pink color of the sediment?
It is caused by the accumulation of the pigment (uroerythrin) on the surface of the granules
861
At what pH are amorphous urates found?
In acidic urine (w/ a pH of > 5.5)
862
At what pH does uric acid crystals appear?
These can appear when the pH is lower
863
What are the characteristics of uric acid crystals?
1) These are seen in variety of shapes including:
a. Rhombic
b. Four-sided plates (whetstones)
c. Wedges
d. Rosettes
2) They usually appear yellow-brown
3) But they may also be colorless and have a six-sided shape (similar to cystine crystals)
4) They are highly birefringent (under polarized light)
864
What is the characteristic of uric acid crystals that aids in distinguishing them from cystine crystals?
They are highly birefringent (under polarized light)
865
Increased amts of uric acid crystals in fresh urine are associated w/ what conditions / disorders?
1) Increased lvls of purines
2) Increased lvls of nucleic acids
3) Seen in pts w/ leukemia (who are receiving chemotherapy)
4) Seen in pts w/ Lesch-Nyhan syndrome
5) Seen sometimes in pts w/ gout
866
What are the characteristics of acid urates and sodium urates?
1) They are rarely encountered
2) They are seen in less acidic urine (like amorphous urates)
3) They are frequently seen in conjunction w/ amorphous urates
4) They have little clinical significance
867
What are the characteristics of acid urates?
1) They appear as larger granules
| 2) They may have spicules (similar to the ammonium biurate crystals seen in alkaline urine)
868
What are the characteristics of sodium urate crystals?
1) They are needle-shaped
2) These are seen in synovial fluid (during episodes of gout)
3) These may also appear in the urine
869
What are the characteristics of calcium oxalate crystals?
1) They are frequently seen in acidic urine
2) But they can be found in urine w/ other pH:
a. Neutral urine
b. Alkaline urine (rarely)
3) Has 2 forms:
a. Dihydrate calcium oxalate
b. Monohydrate calcium oxalate
870
What are the characteristics of dihydrate calcium oxalate?
1) These are the most common form
2) These are easily recognized because:
a. These are colorless
b. Appears as octahedral envelope
c. / these appears as 2 pyramids joined at their bases
871
What are the characteristics of monohydrate calcium oxalate?
1) These are less characteristic
2) These are less frequently seen
3) These are oval
4) / these can be dumbbell shaped
872
What is the characteristic of both dihydrate and monohydrate calcium oxalate?
These are both birefringent (under polarized light)
873
What is the aid of the characteristic of both dihydrate and monohydrate calcium oxalate being birefringent under polarized light?
This may be helpful to distinguish the monohydrate CaOx from nonpolarizing RBCs
874
True or False
CaOx crystals are always seen in clumps attached to mucous strands and may resemble casts
False, because CaOx crystals are sometimes seen in clumps attached to mucous strands and may resemble casts
875
The finding of clumps of CaOx crystals in fresh urine may be related to what conditions / disorders?
1) To the formation of renal calculi (because majority of renal calculi are composed of CaOx)
2) They are also associated w/ foods high in oxalic acid such as:
a. Tomatoes
b. Asparagus
3) They are associated in ascorbic acid (because oxalic acid is an end product of ascorbic acid metabolism)
876
What is the primary pathologic significance of CaOx crystals?
The very noticeable presence of the monohydrate form in cases of ethylene glycol (antifreeze) poisoning
877
To whom are monohydrate CaOx most frequently seen?
In:
1) Pets
2) Children
878
Why are the monohydrate CaOx most frequently seen in children and pets?
Because antifreeze tastes sweet and uncovered containers left in the garage can be tempting (massive amt of crystals are frequently produced in these cases)
879
What are the normal crystals seen in alkaline urine?
1) Phosphates (w/c represents the majority of crystals in alkaline urine) such as:
a. Amorphous phosphate
b. Triple phosphate
c. Calcium phosphate
2) Other crystals associated w/ alkaline urine:
a. Calcium carbonate
b. Ammonium biurate
880
What are the characteristics of amorphous phosphates?
1) They are granular in appearance (similar to amorphous urates)
2) They cause a white ppt that does not dissolve on warming (when amorphous urates are present in large quantities)
881
How can amorphous phosphates be differentiated from amorphous urates (/ what are the factors that can aid in differentiation between amorphous phosphates and amorphous urates)?
By:
1) Color of sediment
2) Urine pH
882
What is the other term for triple phosphate crystals?
Ammonium magnesium phosphate crystals
883
What are the characteristics of triple phosphate crystals?
1) They are commonly seen in alkaline urine
2) They are easily identified by their prism shape that frequently resembles a "coffin lid" (in their routine form)
3) These may develop a feathery appearance (as they disintegrate)
4) These are birefringent (under polarized light)
5) They have no clinical significance (however, they are often seen in highly alkaline urine associated w/ the presence of urea-splitting bacteria)
884
What are the characteristics of calcium phosphate crystals?
1) They are not frequently encountered
2) They may appear:
a. Colorless, flat rectangular plates
b. / thin prisms (often in rosette formations)
3) These dissolve in dilute acetic acid (while sulfonamides do not)
4) They have no clinical significance (although calcium phosphate is a common constituent of renal calculi)
885
When the urine pH is in the neutral range, the rosette forms (of calcium phosphate) may be confused w/ what crystal?
Sulfonamide crystals
886
What are the characteristics of calcium carbonate crystals?
1) These are small
2) These are colorless
3) These have shapes:
a. Dumbbell
b. / spherical
4) They may occur in clumps that resemble amorphous material
5) These are birefringent (w/c differentiates them from bacteria)
6) These have no clinical significance
887
Since calcium carbonate crystals may occur in clumps that resemble amorphous material, how can they be distinguished?
By the formation of gas after the addition of acetic acid
888
What are the characteristics of ammonium biurate crystals?
1) They exhibit the characteristic yellow-brown color (of the urate crystals) seen in acidic urine
2) They are frequently described as "thorny apples" (because of their appearance as spicule-covered spheres)
3) Except for their occurrence in alkaline urine, they resemble other urates (in that they dissolve at 60 DC and convert to uric acid crystals when glacial acetic acid is added)
4) These are almost always encountered in old sxs
5) These may be associated w/ the presence of ammonia (w/c is produced by urea-splitting bacteria)
889
At what pHs are abnormal urine crystals found?
1) Acidic urine
| 2) Neutral urine (rarely)
890
True or False
All abnormal crystals have very characteristic shapes
False, because most abnormal crystals have very characteristic shapes
891
Even if most abnormal crystals have very characteristic shapes, how can their identity be confirmed?
By pt info including:
1) Disorders
2) Medications
892
Iatrogenic crystals can be caused by what?
By a variety of compounds (particularly when they are administered in high concs.)
893
When are abnormal crystals of clinical significance?
When they ppt in the renal tubules
894
What are the most commonly encountered iatrogenic crystals?
1) Cystine crystals
2) Cholesterol crystals
3) Radiographic dye crystals
4) Crystals associated w/ liver disorders:
a. Tyrosine
b. Leucine
c. Bilirubin
895
What are the characteristics of cystine crystals?
1) They are found in the urine of persons who inherit a metabolic disorder that prevents reabsorption of cystine by the renal tubules (cystinuria)
2) They appear as:
a. Colorless, hexagonal plates
b. May be thick / thin
3) May be seen in the presence of ammonia (specifically the disintegrating forms)
4) They may be difficult to differentiate from colorless uric acid crystals
896
What is the characteristic of persons w/ cystinuria?
They have a tendency to form renal calculi (particularly at an early age)
897
How are cystine crystals differentiated from uric acid crystals?
Uric acid crystals are very birefringent under polarized microscopy, whereas only thick cystine crystals have polarizing capability
898
How is positive confirmation of cystine crystals made?
It is made by using the cyanide-nitroprusside test
899
What are the characteristics of cholesterol crystals?
1) These are rarely seen (unless sxs have been refrigerated)
2) They have a most characteristic appearance (when observed) resembling a rectangular plate w/ a notch in 1 or more corners
3) They are associated w/ disorders producing lipiduria such as:
a. Nephrotic syndrome
4) They are seen in conjunction w/:
a. Fatty casts
b. Oval fat bodies
5) They are highly birefringent (w/ polarized light)
900
Why are cholesterol crystals rare seen unless sxs have been refrigerated?
Because the lipids remain in droplet form
901
What are the characteristics of crystals of radiographic contrast media (/ radiographic dye crystals)?
1) They have a very similar appearance to chole crystals
| 2) They are also highly birefringent
902
How is the differentiation of radiographic dye crystals best made?
By comparison of the:
1) Other UA results
2) Pt history
903
Chole crystals should be accompanied by what?
By:
1) Lipid elements
2) Heavy proteinuria
904
What is the status of the SG of a sx containing radiographic contrast media when measured by refractometer?
It is markedly elevated
905
What are the crystals (that may be found in the urine sediment) that are rarely seen in cases of severe liver disorders)?
1) Tyrosine crystals
2) Leucine crystals
3) Bilirubin crystals
906
What are the characteristics of tyrosine crystals?
1) They appear as fine colorless to yellow needles
2) They frequently form:
a. Clumps
b. / rosettes
3) They are usually seen in conjunction w/ leucine crystals (in sxs w/ [+] chemical test results for bili)
4) They may also be encountered in inherited disorders of amino acid metabolism
907
What are the characteristics of leucine crystals?
1) They are yellow-brown spheres
2) They demonstrate:
a. Concentric circles
b. Radial striations
3) They are seen less frequently than tyrosine crystals
4) They should be accompanied by tyrosine crystals (when leucine crystals are present)
908
What are the characteristics of bili crystals?
1) They are present in hepatic disorders producing large amts of bili in the urine
2) They appear as clumped needles / granules
3) They have a characteristic yellow color of bili
4) When present, a (+) chemical test result for bili would be expected
5) These may be found incorporated into the matrix of casts in cases of disorders that produce renal tubular damage such as:
a. Viral hepatitis
909
True or False
Prior to the development of more soluble sulfonamides, the finding of sulfonamide crystals in the urine of pts being treated for UTIs was common
True
910
What was and still the primary cause of sulfonamide crystallization?
Inadequate pt hydration
911
The appearance of sulfonamide crystals in fresh urine suggest what condition / disorder?
Suggest the possibility of tubular damage (if crystals are forming in the nephron)
912
True or False
There are no sulfonamide medications currently available on the market
False, because a variety of sulfonamide medications are currently available in the market
913
Since a variety of sulfonamide medications are currently on the market, what can be expected?
One can expect to encounter a variety of crystal shapes and colors (of sulfonamide crystals)
914
What are the shapes (of sulfonamide crystals) that are most frequently encountered?
1) Needles
2) Rhombics
3) Whetstones
4) Sheaves of wheat
5) Rosettes (w/ colors ranging from colorless to yellow-brown)
915
What should be done that aids in the identification confirmation of sulfonamide crystals?
A check of the pt's medication history
916
True or False
Precipitation of antibiotics is not frequently encountered except for the rare observation of ampicillin crystals following massive doses of this penicillin compound w/out adequate hydration
True
917
What is the characteristic of ampicillin crystals?
They appear as colorless needles (that tend to form bundles following refrigeration)
918
What can be done to aid the identification of ampicillin crystals?
Knowledge of pt's history
919
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: Uric acid
1) Acid
| 2) Yellow-brown (rosettes, wedges)
920
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: Amorphous urates
1) Acid
| 2) Brick dust / yellow brown
921
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: CaOx
1) Acid / neutral (alkaline)
| 2) Colorless (envelopes, oval, dumbbell)
922
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: Amorphous phosphates
1) Alkaline / neutral
| 2) White to colorless
923
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: Calcium phosphate
1) Alkaline / neutral
| 2) Colorless
924
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: Triple phosphate
1) Alkaline
| 2) Colorless ("coffin lids")
925
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: Ammonium biurate
1) Alkaline
| 2) Yellow-brown ("thorny apples")
926
Answer the ff questions w/ regards to the given normal urinary crystal:
1) At what pH/s does it occur?
2) What is its color?
Given normal urinary crystal: Calcium carbonate
1) Alkaline
| 2) Colorless (dumbbells)
927
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Cystine
1) Acid
2) Colorless (hexagonal plates)
3) Inherited cystinuria
928
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Cholesterol
1) Acid
2) Colorless (notched plates)
3) Nephrotic syndrome
929
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Leucine
1) Acid / neutral
2) Yellow (concentric circles)
3) Liver disease
930
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Tyrosine
1) Acid / neutral
2) Colorless to yellow (needles)
3) Liver disease
931
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Bili
1) Acid
2) Yellow
3) Liver disease
932
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Sulfonamides
1) Acid / neutral
2) Varied
3) Infection treatment
933
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Radiographic dye
1) Acid
2) Colorless (flat plates)
3) Radiographic procedure
934
Answer the ff questions w/ regards to the given abnormal urinary crystal:
1) At what pH/s does it occur?
2) What is its color / form?
3) What is/are its associated disorder/s?
Given normal urinary crystal: Ampicillin
1) Acid / neutral
2) Colorless (needles)
3) Infection treatment
935
True or False
Contaminants of all types can be found in urine, particularly sxs collected under improper conditions or in dirty containers
True
936
What are the most frequently encountered artifacts?
1) Starch
2) Oil droplets
3) Air bubbles
4) Pollen grains
5) Fibers
6) Fecal contamination
937
True or False
Because artifacts frequently resemble pathologic elements (such as RBCs and casts), artifacts can present a major problem to students
True
938
What are the characteristics of urinary sediment artifacts?
1) They are often very highly refractile
| 2) / they occur in a different microscopic plane (than true sediment constituents)
939
Is the reporting of artifacts necessary?
No
940
When can starch granule contamination may occur?
When starch is the powder used in powdered gloves
941
What are the characteristics of granules (/ starch granules)?
1) They are highly refractile spheres
2) They usually have a dimpled center
3) They resemble fat droplets when polarized (producing a Maltese cross formation)
4) They may also occasionally be confused w/ RBCs
942
How can the differentiation between starch and pathologic elements be made?
1) By considering other UA results including chemical tests for:
a. Blood
b. / protein
2) Presence of:
a. Oval fat bodies
b. / fatty casts
943
What are the characteristics of oil droplets and air bubbles?
1) They are highly refractile
| 2) They may resemble RBCs to inexperienced lab personnel
944
Presence of oil droplets may result from what?
1) From contamination by:
a. Immersion oil
b. / lotions
c. / creams
2) They may be seen w/ fecal contamination
945
When do air bubbles occur?
When the sx is placed under a cover slip
946
True or False
The presence of artifacts (such as oil droplets and air bubbles) should be considered in the context of other UA results
True
947
What are pollen grains?
These are seasonal contaminants
948
What are the characteristics of pollen grains?
1) They appear as spheres w/:
a. A cell wall
b. Occasional concentric circles
2) They have a large size (w/c may cause them to be out of focus w/ true sediment constituents)
949
What are the characteristics of hair and fibers from clothing and diapers?
1) They may initially be mistaken for casts
| 2) But they are usually much longer and more refractile (than casts)
950
What should be done to frequently differentiate between fibers and casts?
Examination under polarized light
951
In terms of differentiation between fibers and casts, what is the characteristic of fibers?
They often polarize
952
In terms of differentiation between fibers and casts, what is the characteristic of casts?
They do not polarize (other than fatty casts)
953
What are the events / conditions that may produce fecal sx contamination?
1) Improperly collected sxs
| 2) / presence of a fistula between the intestinal and urinary tracts (rarely)
954
What are the characteristics of fecal artifacts?
They may appear as:
a. Plant
b. Meat fibers
c. / as brown amorphous material (in a variety of sizes and shapes)
