Chemical Examination of Urine Flashcards
1
Q
Provide, simple, rapid means for performing medically significant analysis of urine
A
Reagent strips
2
Q
Reagent strips consist of _____ absorbent pads attached to a plastic strip
A
Chemical-impregnated
3
Q
Specimen required for chemical testing of urine
A
A fresh, well-mixed, uncentrifuged specimen
4
Q
10 parameters for chemical examination of urine
A
pH
Protein
Glucose
Ketones
Blood
Bilirubin
Urobilinogen
Nitrite
Leukocytes
Specific gravity
5
Q
11th parameter for chemical examination of urine
A
Ascorbic acid or Vitamin C
6
Q
Two major types of reagent strip are manufactured under
A
Multistix & Chemstrip
7
Q
Dipping time of reagent strips
A
No longer than 1 second
8
Q
Major regulators of the acid–base content in the body
A
Kidneys
9
Q
Importance of pH determination
A
Identification of urinary crystals
Determination of unsatisfactory specimens
10
Q
Normal random urine pH
A
4.5-8.0
11
Q
First morning urine pH
A
5.0-6.0
12
Q
Freshly voided urine pH
A
Not >8.5 in normal or abnormal conditions
13
Q
pH of improperly preserved specimen
A
> 9 or >8.5
14
Q
Presence of _____ in urine container can cause alkalization of urine
A
Detergent
15
Q
Home remedy for minor bladder infections
A
Cranberry juice or pills
16
Q
Principle of reagent strip reaction for pH
A
Double Indicator System
17
Q
Reading time of reagent strip reaction for pH
A
60 seconds
18
Q
Reagents for pH testing
A
Methyl Red
Bromthymol Blue
19
Q
Density of a solution compared with density of similar volume of distilled water at a similar temperature
A
Specific gravity
20
Q
S.G. is influenced by
A
Number and size of particles on a solution
21
Q
What does the reagent strip S.G. test measure?
A
Only ionic solutes
22
Q
Normal random S.G.
A
1.002-1.035
23
Q
Radiographic Contrast dye S.G.:
A
> 1.040
24
Q
Not a urine S.G
A
<1.002
25
Principle of reagent strip reaction for S.G.
Change in the pKa (dissociation constant) of a polyelectrolyte
26
Reading time of reagent strip reaction for S.G.
45 seconds
27
Reagents for S.G. testing
Multistix: Poly (methyl vinyl ether/ maleic anhydride) bromthymol blue
Chemstrip: Ethylene glycol diaminoethyl ether tetraacetic acid, bromthymol blue
28
Parameter that is most indicative of renal disease
Protein
29
Normal urine protein
<10 mg/dL or 100 mg/24 hours (Strasinger)
<150mg/24 hours (Henry’s)
30
Major protein found in normal urine
Albumin
31
Protein produces a yellow foam in urine. True or False?
False; white foam
32
Other Proteins normally found in urine
Serum and tubular microglobulins
Tamm-Horsfall protein (Uromodulin)
Protein derived from prostatic and vaginal secretion
33
Result that indicates clinical proteinuria
≥30mg/dL or ≥300mg/L
34
Three categories of proteinuria
Prerenal
Renal
Postrenal
35
Proteinuria caused by conditions that affect the plasma prior to it reaching the kidney
Prerenal proteinuria/Overflow proteinuria
36
A monoclonal immunoglobulin light chains (kappa and lambda) found in cases of Multiple myeloma
Bence Jones protein
37
Bence Jones protein in heat reactivity test
Coagulates/Precipitates at 40-60C and dissolves at 100C
38
Confirmatory Test for Bence Jones protein
Serum electrophoresis
39
Proteinuria associated with true renal disease may be the result of either glomerular or tubular damage
Renal proteinuria/True renal disease
40
Amount of protein following glomerular damage
Slightly above normal to 4 g/day
41
The presence of albumin in urine above the normal level but below the detectable range of conventional urine dipstick methods
Microalbuminuria
42
Diabetic Nephropathy is also known as
Kimmelstiel-Wilson’s disease
43
Indicator of Kimmelstiel-Wilson’s disease
Microalbuminuria
44
Normal Albumin Excretion Rate (AER)
0-20 µg/min
45
AER corresponding to microalbuminuria
0-300 mg of albumin is excreted in 24 hours or the AER is 20-200 µg/min
46
Immunochemical assays for microalbuminuria
Micral-Test
ImmunoDip
47
Principle of Micral-Test
Enzyme immunoassay
48
Reagents for Micral-Test
Gold-labeled antibody
B-galactosidase
Chlorophenol red galactoside
49
Dipping time of strips in Micral-Test
5 seconds
50
Reading time of Micral-Test
1 minute
51
(+) Micral-Test
Red
52
(-) Micral-Test
White
53
Principle of ImmunoDip
Immunochromographic technique
54
Reagents for ImmunoDip
Antibody-coated blue latex particles
55
Dipping time of strips in ImmunoDip
3 minutes
56
(+) ImmunoDip
Darker top band; 2 -8
57
Borderline ImmunoDip
Equal band colors; 1.2-1.8
58
(-) ImmunoDip
Darker bottom band; <1.2
59
Normal creatinine value
10-300 mg/dL
60
Abnormal A:C Ratio
30-300 mg/g or 3.4-33.9 mg/mmol
61
Principle of A:C ratio
Sensitive albumin tests related to creatine concentration to correct for patient hydration
62
Reagent of albumin strip
dye bis (3',3"-diiodo-4',4"-dihydroxy-5',5" dinitrophenyl)-3,4,5,6-tetrabromo sulphonphthalein (DIDNTB)
63
Principle of creatinine strip test
Pseudoperoxidase activity of copper-creatinine complexes
64
Reagent of creatinine strip
Copper sulfate (CuSO4), 3,3',5,5'-tetramethylbenzidine (TMB),
Diisopropyl benzene dihydroperoxide (DBDH)
65
Occurs following periods spent in a vertical posture and disappears when a horizontal position is assumed
Orthostatic / Cadet / Postural proteinuria
66
Disease where normally filtered albumin can no longer be reabsorbed
Tubular proteinuria
67
Principle of reagent strip reaction for protein
Protein (Sorensen’s) error of indicator
68
Reagents for protein strip testing
Multistix: Tetrabromphenol blue
Chemstrip: 3’,3’’,5’,5’’-tetrachlorophenol 3,4,5,6-tetrabromosulfophthalein
69
Reading time of reagent strip reaction for protein
60 seconds
70
A cold precipitation test that reacts equally with all forms of protein
Sulfosalicylic acid precipitation test
71
(+) SSA & (+) RGT STRP
Presence of ALBUMIN
72
(+) SSA & (-) RGT STRP
Presence of proteins OTHER THAN ALBUMIN
73
Microscopically, what is the SSA pattern if proteins cause a positive reaction?
Amorphous
74
Microscopically, what is the SSA pattern if drugs and radiographic contrast dye cause a positive reaction?
Crystalline
75
Most frequently performed chemical analysis on urine (due to detection and monitoring of DM)
Glucose test
76
Renal threshold for glucose
160-180 mg/dL
77
Specimen used for diabetes monitoring
2-hour postprandial
78
Glucose and insulin can cross the placenta. True or False?
False; glucose crosses the placenta whereas insulin does not
79
Effect of GDM to the baby
Large baby (macrosomia) at risk for obesity and later type 2 diabetes
80
Effect of GDM to the mother
Prone to developing type 2 diabetes mellitus in later years
81
Hyperglycemia – Associated urine glucose
Increased blood glucose, Increased Urine glucose
82
Renal – Associated urine glucose
Normal blood glucose, Increased Urine glucose
83
Principle of reagent strip reaction for glucose
Double sequential enzyme reaction
84
Reading time of reagent strip reaction for glucose
30 seconds
85
Reagents for glucose strip testing
Multistix: glucose oxidase, peroxidase, Potassium iodide (blue to green to brown)
Chemstrip: glucose oxidase, peroxidase, tetramethylbenzidine (yellow to green)
86
Principle of Copper Reduction Test (Clinitest/Benedict's Test)
Copper Reduction
87
Component of the Tablet (Copper Reduction Test) and their function
Copper sulfate: main reacting agent
Sodium carbonate: eliminates interfering O2 (room air)
Sodium citrate /citric acid: for heat production
Sodium hydroxide: for heat production
88
(+) glucose oxidase (+) clinitest
Presence of glucose
89
(-) glucose oxidase (+) clinitest
Presence of non-glucose reducing substance
90
(1+) glucose oxidase (-) clinitest
Small amount of glucose
91
(4+) glucose oxidase (-) clinitest
False-positive reagent strip
False negative Clinitest
Defective Clinitest tablets (outdated)
92
Result from increased fat metabolism. They are formed from beta oxidation of fats
Ketones
93
Most valuable in the management and monitoring of insulin-dependent (type 1) diabetes mellitus
Testing for urinary ketones
94
Ketone Renal Threshold
70 mg/dL
95
Ketone Bodies
78% Beta Hydroxybutyric acid
20% Acetoacetic acid (AAA) / Diacetic acid
2 % Acetone
96
Early indicator of insufficient insulin dosage in type 1 diabetes
Ketonuria
97
Principle of reagent strip reaction for ketones
Legal’s Test (Sodium Nitroprusside)
98
Reading time of reagent strip reaction for ketones
40 seconds
99
Reagents for ketone strip testing
Sodium nitroprusside (nitroferricyanide),
Glycine (Chemstrip)
100
Components of the acetest tablet
Sodium nitroprusside
Glycine
Disodium phosphate
Lactose
101
Reading time of acetest
30 seconds
102
The finding of a positive reagent strip test result for blood indicates the presence of
Red blood cells
Hemoglobin
Myoglobin
103
Clarity of urine with hematuria
Cloudy red urine
104
Clarity of urine with hemoglobinuria
Clear red urine
105
Clarity of urine with myoglobinuria
Clear red urine
106
Amount of blood that is clinically significant
>5 cells/µL of urine
107
Why is it that chemical tests for hemoglobin provide the most accurate means for determining the presence of blood?
Because microscopic examination of the urinary sediment shows intact red blood cells, but free hemoglobin produced either by hemolytic disorders or lysis of red blood cells is not detected
108
The heme portion of myoglobin is toxic to the renal tubules, and high concentrations can cause acute renal failure. True or False?
True
109
The massive hemoglobinuria seen in hemolytic transfusion reactions also is associated with
Acute renal failure
110
Appearance of plasma when hemoglobin is present
Red/ pink plasma
111
Appearance of plasma when myoglobin is present
Pale yellow plasma
112
Precipitation test used to differentiate hemoglobin from myoglobin
Blondheim’s precipitation test (ammonium sulfate)
113
Blondheim’s precipitation test result of hemoglobin
Precipitated by ammonium sulfate
Produce a clear supernatant that is negative for blood reagent strip
114
Blondheim’s precipitation test result of myoglobin
Not precipitated by ammonium sulfate
Produce a red supernatant that is positive for blood reagent strip
115
Principle of reagent strip reaction for blood
Pseudoperoxidase activity of Hemoglobin
116
Reading time of reagent strip reaction for blood
60 seconds
117
Reagents for blood strip testing
Multistix: diisopropylbenzene dihydroperoxide and 3,3’,5,5’-tetramethylbenzidine
Chemstrip: dimethyldihydroperoxyhexane and tetramethylbenzidine
118
Pattern of of pads when hemoglobin/myoglobin is detected
Uniform
119
Pattern of of pads when RBC is detected
Speckled
120
A highly pigmented yellow compound, is a degradation product of hemoglobin
Bilirubin
121
The appearance of bilirubin in the urine indicates
Early indication of liver disease
122
Why does jaundice due to increased destruction of red blood cells does not produce bilirubinuria?
Because the serum bilirubin is present in the unconjugated form and the kidneys cannot excrete it
123
Jaundice associated with hemolytic disorders results from the increased amount of circulating unconjugated bilirubin. True or False?
True
124
Form of bilirubin that is water soluble and can be seen in urine
B2 or conjugated bilirubin
125
Bilirubin produces an amber urine with white foam. True or False?
False; yellow foam
126
Amount of bilirubin normal adult urine
0.02 mg/dL
127
Principle of reagent strip reaction for bilirubin
Diazo Reaction
128
Reading time of reagent strip reaction for bilirubin
30 seconds
129
Reagents for bilirubin strip testing
Multistix: 2,4-dichloroaniline diazonium salt
Chemstrip: 2,6-dichlorobenze diazonium salt/tetrafluoroborate
130
A confirmatory test for bilirubin
Ictotest
131
Positive reaction
of Ictotest
Blue to purple color
132
Negative reaction of Ictotest
Colors other than blue or purple
133
How to remove interferences in Ictotest?
Add water
134
Reading time of Ictotest
30 seconds
135
A bile pigment that results from hemoglobin degradation
Urobilinogen
136
Amount of urobilinogen normally found in urine
<1 mg/dL or Ehrlich unit
137
>1 mg/dL of urobilinogen indicates
Liver disease and hemolytic disorders
138
Absence of urobilinogen in the urine and feces indicates
Bile duct obstruction
139
Stool color when there is a lack of urobilin
Pale
140
Principle of reagent strip reaction for urobilinogen
Ehrlich‘s reaction
141
Reading time of reagent strip reaction for urobilinogen
60 seconds
142
Reagents for urobilinogen strip testing
Multistix: p-dimethylaminobenzaldehyde
Chemstrip: 4-methoxybenzene diazonium tetrafluroborate
143
What would be the result of urobilinogen measurements if the reagent strip is performed at a higher temperature?
Falsely increased
144
What would be the result of urobilinogen measurements after following a meal?
Normally highest after meal
145
Used to differentiate urobilinogen, porphobilinogen, and other Ehrlich reactive compounds
Watson-Schwartz Test
146
Review Watson-Schwartz Test
REVIEWHIN MO SA NOTES
147
Rapid screening and monitoring test for urine porphobilinogen (>2mg/dL)
Hoesch Test (Inverse Ehrlich Reaction)
148
Provides a rapid screening test for the presence of UTI and bacteriuria
Nitrite
149
The nitrite test also can be used to:
Evaluate the success of antibiotic therapy
Periodically screen persons with recurrent infections, patients with diabetes
Pregnant women
150
Nitrite test is intended to replace the urine culture as the primary test for diagnosing and monitoring bacterial infection. True or False?
False; not intended
151
Specimens used for nitrite test
1st morning or 4 hours urine
152
The chemical basis of the nitrite test
The ability of certain bacteria to reduce nitrate, a normal constituent of urine, to nitrite, which does not normally appear in the urine
153
Principle of reagent strip reaction for nitrite
Greiss reaction
154
Reading time of reagent strip reaction for nitrite
60 seconds
155
Reagents for nitrite strip testing
Multistix: p-arsanilic acid, tehtrahydrobenzoquinolin-3-ol
Chemstrip: sulfanilamide, hydroxytetrahydro benzoquinoline
156
Positive result of nitrite strip testing
Uniform/Homogenous pink
157
Pink spots/edge result of nitrite strip testing is considered
Negative
158
Positive nitrite corresponds to
>100,000 organisms/mL
159
Significance of leukocyte testing
UTI/inflammation
Screening of urine culture specimen
Bacterial and non-bacterial infection
160
LE test detects esterase found in:
Granulocytic WBCs (Neutrophil, Eosinophil, Basophil)
Monocytes
Trichomonas
Chlamydia
Yeast
Histiocytes
161
Esterase negative constituents
Lymphocytes
Erythrocytes
Bacteria
Renal tissue cells
162
Infections involving trichomonads, mycoses (yeast), chlamydia, mycoplasmas, viruses, or tuberculosis cause
Leukocyturia or pyuria without bacteriuria
163
Screening urine specimens using LE test should be correlated with
Nitrite chemical reactions
164
Principle of reagent strip reaction for leukocyte
Leukocyte Esterase
165
Reading time of reagent strip reaction for leukocyte
120 seconds
166
Reagents for lekocyte strip testing
Multistix: Diazonium salt, derivatized pyrrole amino acid ester
Chemstrip: Diazonium salt, Indoxylcarbonic acid ester
167
11th parameter
Ascorbic acid
168
Ascorbic acid causes False Negative result to
BBLNG (Blood, Bilirubin, Leukocyte, Nitrite, Glucose)
169
Ascorbic acid causes False Positive result to
Clinitest
170
Ascorbic acid level that causes a negative reaction to Bilirubin and Nitrite
≥25 mg/dL
171
Ascorbic acid level that causes a negative reaction to glucose
≥50 mg/dL
172
Reading time of Stix
60 seconds
173
Reading time of C-stix
10 seconds
174
Positive result of Stix
Blue color
175
Positive result of C-stix
Blue color
