Chapter 6 Microscopic Examination of Urine Flashcards
Macroscopic screening of urine specimens is used to:
A. Provide results as soon as possible
B. Predict the type of urinary casts present
C. Increase cost-effectiveness of urinalysis
D. Decrease the need for polarized microscopy
A
Variations in the microscopic analysis of urine include all of the following except: A. Preparation of the urine sediment B. Amount of sediment analyzed C. Method of reporting D. Identification of formed elements
D
All of the following can cause false-negative microscopic results except: A. Braking the centrifuge B. Failing to mix the specimen C. Dilute alkaline urine D. Using midstream clean-catch specimens
C
The two factors that determine relative centrifugal force are:
A. Radius of rotor head and rpm
B. Radius of rotor head and time of centrifugation
C. Diameter of rotor head and rpm
D. RPM and time of centrifugation
C
When using the glass slide and cover-slip method, which of
the following might be missed if the cover slip is overflowed?
A. Casts
B. RBCs
C. WBCs
D. Bacteria
A
Initial screening of the urine sediment is performed using an objective power of: A. 4× B. 10× C. 40× D. 100×
B
Which of the following should be used to reduce light intensity in bright-field microscopy? A. Centering screws B. Aperture diaphragm C. Rheostat D. Condenser aperture diaphragm
C
Which of the following are reported as number per lpf? A. RBCs B. WBCs C. Crystals D. Casts
D
The Sternheimer-Malbin stain is added to urine sediments
to do all of the following except:
A. Increase visibility of sediment constituents
B. Change the constituents’ refractive index
C. Decrease precipitation of crystals
D. Delineate constituent structures
C
Nuclear detail can be enhanced by: A. Prussian blue B. Toluidine blue C. Acetic acid D. Both B and C
D
Which of the following lipids is/are stained by Sudan III? A. Cholesterol B. Neutral fats C. Triglycerides D. Both B and C
D
Which of the following lipids is/are capable of polarizing light? A. Cholesterol B. Neutral fats C. Triglycerides D. Both A and B
A
The purpose of the Hansel stain is to identify: A. Neutrophils B. Renal tubular cells C. Eosinophils D. Monocytes
C
Crenated RBCs are seen in urine that is: A. Hyposthenuric B. Hypersthenuric C. Highly acidic D. Highly alkaline
B
Differentiation among RBCs, yeast, and oil droplets may
be accomplished by all of the following except:
A. Observation of budding in yeast cells
B. Increased refractility of oil droplets
C. Lysis of yeast cells by acetic acid
D. Lysis of RBCs by acetic acid
C
A finding of dysmorphic RBCs is indicative of: A. Glomerular bleeding B. Renal calculi C. Traumatic injury D. Coagulation disorders
A
Leukocytes that stain pale blue with Sternheimer-Malbin stain and exhibit brownian movement are: A. Indicative of pyelonephritis B. Basophils C. Mononuclear leukocytes D. Glitter cells
D
Mononuclear leukocytes are sometimes mistaken for: A. Yeast cells B. Squamous epithelial cells C. Pollen grains D. Renal tubular cells
D
When pyuria is detected in a urine sediment, the slide
should be carefully checked for the presence of:
A. RBCs
B. Bacteria
C. Hyaline casts
D. Mucus
B
Transitional epithelial cells are sloughed from the: A. Collecting duct B. Vagina C. Bladder D. Proximal convoluted tubule
C
The largest cells in the urine sediment are: A. Squamous epithelial cells B. Urothelial epithelial cells C. Cuboidal epithelial cells D. Columnar epithelial cells
A
A clinically significant squamous epithelial cell is the: A. Cuboidal cell B. Clue cell C. Caudate cell D. Columnar cell
B
Forms of transitional epithelial cells include all of the following except: A. Spherical B. Caudate C. Convoluted D. Polyhedral
C
Increased transitional cells are indicative of: A. Catheterization B. Malignancy C. Pyelonephritis D. Both A and B
D
A primary characteristic used to identify renal tubular epithelial cells is: A. Elongated structure B. Centrally located nucleus C. Spherical appearance D. Eccentrically located nucleus
D
Following an episode of hemoglobinuria, RTE cells may contain: A. Bilirubin B. Hemosiderin granules C. Porphobilinogen D. Myoglobin
B
The predecessor of the oval fat body is the: A. Histiocyte B. Urothelial cell C. Monocyte D. Renal tubular cell
D
A structure believed to be an oval fat body produced a
Maltese cross formation under polarized light but does not
stain with Sudan III. The structure:
A. Contains cholesterol
B. Is not an oval fat body
C. Contains neutral fats
D. Is contaminated with immersion oil
A
The finding of yeast cells in the urine is commonly associated with: A. Cystitis B. Diabetes mellitus C. Pyelonephritis D. Liver disorders
B
The primary component of urinary mucus is: A. Bence Jones protein B. Microalbumin C. Uromodulin D. Orthostatic protein
C
The majority of casts are formed in the: A. Proximal convoluted tubules B. Ascending loop of Henle C. Distal convoluted tubules D. Collecting ducts
C
Cylindruria refers to the presence of: A. Cylindrical renal tubular cells B. Mucus-resembling casts C. Hyaline and waxy casts D. All types of casts
D
A person submitting a urine specimen following a strenuous
exercise routine can normally have all of the following
in the sediment except:
A. Hyaline casts
B. Granular casts
C. RBC casts
D. WBC casts
D
Prior to identifying an RBC cast, all of the following
should be observed except:
A. Free-floating RBCs
B. Intact RBCs in the cast
C. Presence of a cast matrix
D. A positive reagent strip blood reaction
B
WBC casts are primarily associated with: A. Pyelonephritis B. Cystitis C. Glomerulonephritis D. Viral infections
A
The shape of the RTE cell associated with renal tubular epithelial casts is primarily: A. Elongated B. Cuboidal C. Round D. Columnar
C
When observing RTE casts, the cells are primarily:
A. Embedded in a clear matrix
B. Embedded in a granular matrix
C. Attached to the surface of a matrix
D. Stained by components of the urine filtrate
A
The presence of fatty casts is associated with: A. Nephrotic syndrome B. Crush injuries C. Diabetes mellitus D. All of the above
D
Nonpathogenic granular casts contain: A. Cellular lysosomes B. Degenerated cells C. Protein aggregates D. Gram-positive cocci
A
All of the following are true about waxy casts except they: A. Represent extreme urine stasis B. May have a brittle consistency C. Require staining to be visualized D. Contain degenerated granules
C
Observation of broad casts represents: A. Destruction of tubular walls B. Dehydration and high fever C. Formation in the collecting ducts D. Both A and C
D
All of the following contribute to urinary crystals formation except: A. Protein concentration B. pH C. Solute concentration D. Temperature
A
The most valuable initial aid for identifying crystals in a urine specimen is: A. pH B. Solubility C. Staining D. Polarized microscopy
A
Crystals associated with severe liver disease include all of the following except: A. Bilirubin B. Leucine C. Cystine D. Tyrosine
C
All of the following crystals routinely polarize except: A. Uric acid B. Cholesterol C. Radiographic dye D. Cystine
D
Casts and fibers can usually be differentiated using: A. Solubility characteristics B. Patient history C. Polarized light D. Fluorescent light
C
Match the following crystals seen in acidic urine with their description/identifying characteristics: \_\_\_\_ Amorphous urates \_\_\_\_ Uric acid \_\_\_\_ Calcium oxalate monohydrate \_\_\_\_ Calcium oxalate dihydrate
- Envelopes
- Thin needles
- Yellow-brown, whetstone
- Pink sediment
- Ovoid
4, 3, 5, 1
Match the following crystals seen in alkaline urine with
their description/identifying characteristics:
____ Triple phosphate
____ Amorphous phosphate
____ Calcium phosphate
____ Ammonium biurate
____ Calcium carbonate
- Yellow granules
- Thin prisms
- “Coffin lids”
- Dumbbell shape
- White precipitate
- Thorny apple
3 5 2 6 4
Match the following abnormal crystals with their description/identifying characteristics: \_\_\_\_ Cystine \_\_\_\_ Tyrosine \_\_\_\_ Cholesterol \_\_\_\_ Leucine \_\_\_\_ Ampicillin \_\_\_\_ Radiographic dye \_\_\_\_ Bilirubin
- Bundles following refrigeration
- Highly alkaline pH
- Bright yellow clumps
- Hexagonal plates
- Flat plates, high specific gravity
- Concentric circles, radial striations
- Notched corners
- Fine needles seen in liver disease
4 8 7 6 1 5 3
Match the following types of microscopy with their descriptions: \_\_\_\_ Bright-field \_\_\_\_ Phase \_\_\_\_ Polarized \_\_\_\_ Dark-field \_\_\_\_Fluorescent \_\_\_\_Interference
- Indirect light is reflected off the object
- Objects split light into two beams
- Low refractive index objects may be overlooked
- Three-dimensional images
- Forms halo of light around object
- Detects electrons contrast emitted from objects
- Detects specific wavelengths
of light emitted from objects
3 5 2 1 7 4
An 85-year-old woman with diabetes and a broken hip has been confined to bed for the past 3 months. Results of an ancillary blood glucose test are 250 mg/dL, and her physician orders additional blood tests and a routine urinalysis. The urinalysis report is as follows:
COLOR: Pale yellow KETONES: Negative CLARITY: Hazy BLOOD: Moderate SP. GRAVITY: 1.020 BILIRUBIN: Negative pH: 5.5 UROBILINOGEN: Normal PROTEIN: Trace NITRITE: Negative GLUCOSE: 100 mg/dL LEUKOCYTES: 2+
Microscopic:
20 to 25 WBCs/hpf
Many yeast cells and hyphae
a. Why are yeast infections common in patients with diabetes mellitus?
b. With a blood glucose level of 250 mg/dL, should glucose be present in the urine? Why or why not?
c. Is there a discrepancy between the negative nitrite and the positive leukocyte esterase results? Explain your answer.
d. What is the major discrepancy between the chemical and microscopic results?
e. Considering the patient’s history, what is the most probable cause for the discrepancy?
a. Yeast grows best at a low pH with an increased concentration of glucose.
b. Yes, this exceeds the renal threshold.
c. No, yeast is not capable of reducing nitrate to nitrite.
d. Moderate blood with no RBCs.
e. Myoglobin is the cause of the positive chemical test result for blood. The patient has been bed-ridden for an extended period of time, causing muscle destruction.
A medical technology student training in a newly renovated STAT laboratory is having difficulty performing a microscopic urinalysis. Reagent strip testing indicates the presence of moderate blood and leukocytes, but the student is also observing some large unusual objects resembling crystals and possible casts. The student is also having difficulty keeping all of the constituents in focus at the same time.
a. Why is the student having difficulty focusing?
b. What is a possible cause of the unusual microscopic constituents?
c. Should the student be concerned about the unusual microscopic constituents? Explain your answer.
d. What microscopy technique could be used to aid in differentiating a cast and an artifact?
a. The large objects are in a different plane from that of the urinary constituents.
b. Contamination by artifacts.
c. No, because they are in a different plane.
d. Polarizing microscopy.
A prisoner sentenced to 10 years for selling illegal drugs develops jaundice, lethargy, and hepatomegaly. A test for hepatitis B surface antigen is positive, and the patient is placed in the prison infirmary. When his condition appears to worsen and a low urinary output is observed, the patient is transferred to a local hospital.
a. Based on the urinalysis results, in what area of the nephron is damage occurring?
b. Is this consistent with the patient’s
primary diagnosis? Explain your answer.
c. What is causing the RTE cells to be bile stained?
d. Why is the urobilinogen level elevated?
e. State a disorder in which the urobilinogen level would be elevated, but the bilirubin result would be negative.
a. Renal tubules.
b. Yes, viral infections can cause tubular damage.
c. RTE cells absorb the bilirubin-containing urinary filtrate.
d. Liver damage inhibits processing of reabsorbed urobilinogen.
e. Hemolytic anemia.
A 30-year-old woman being treated for a UTI brings a urine specimen to the Employee Health Clinic at 4:00 p.m.
The nurse on duty tells her that the specimen will be refrigerated and tested by the technologist the next morning.
The technologist has difficulty interpreting the color of the reagent strip tests and reports only the following results:
COLOR: Amber
CLARITY: Slightly cloudy
Microscopic: 3 to 5 RBCs/hpf 8 to 10 WBCs/hpf Moderate bacteria Moderate colorless crystals appearing in bundles
a. What could have caused the technologist to have difficulty interpreting the reagent strip results?
b. Could this specimen produce a yellow foam when shaken?
c. What could the technologist do to aid in the identification of the crystals?
d. What is the probable identification of the colorless crystals?
a. The patient is taking a pigmented medication, such as phenazopyridine.
b. Yes.
c. Ask what medications the patient is taking.
d. Ampicillin
A 2-year-old left unattended in the garage for 5 minutes is suspected of ingesting antifreeze (ethylene glycol). The urinalysis has a pH of 6.0 and is negative on the chemical examination. Two distinct forms of crystals are observed in the microscopic examination.
a. What type of crystals would you expect to be present?
b. What is the other form of this crystal?
c. Describe the two forms.
d. Which form would you expect to be predominant?
a. Calcium oxalate
b. Monohydrate and dihydrate calcium oxalate
c. Oval: monohydrate; envelope: dihydrate
d. Monohydrate
A female patient comes to the outpatient clinic with symptoms of UTI. She brings a urine specimen with her. Results of the routine analysis performed on this specimen are as follows:
COLOR: Yellow KETONES: Negative CLARITY: Hazy BLOOD: Small SP. GRAVITY: 1.015 BILIRUBIN: Negative pH: 9.0 UROBILINOGEN: Normal PROTEIN: Negative NITRITE: Negative GLUCOSE: Negative LEUKOCYTE: 2+
Microscopic: 1 to 3 RBCs/hpf Heavy bacteria 8 to 10 WBCs/hpf Moderate squamous epithelial cells
a. What discrepancies are present between the chemical and microscopic test results?
b. State a reason for the discrepancies.
c. Identify a chemical result in the urinalysis that confirms your reason for the discrepancies.
d. What course of action should the laboratory take to obtain accurate results for this patient?
a. Microscopic results do not match the chemical tests for blood, nitrite, and leukocyte esterase.
b. The specimen has been unpreserved at room temperature for too long, the cells have disintegrated, and the bacteria have converted the nitrite to nitrogen.
c. The pH.
d. Ask the clinic personnel to instruct the patient to collect a midstream clean-catch specimen and have the specimen delivered immediately to the laboratory.
A high school student is taken to the emergency room with a broken leg that occurred during a football game. The urinalysis results are as follows:
COLOR: Dark yellow KETONES: Negative CLARITY: Hazy BLOOD: Moderate SP. GRAVITY: 1.030 BILIRUBIN: Negative pH: 5.5 UROBILINOGEN: Normal PROTEIN: 2+ NITRITE: Negative GLUCOSE: Negative LEUKOCYTE: Negative
Microscopic: 0 to 3 WBCs/hpf 0 to 4 hyaline casts/lpf 0 to 3 granular casts/lpf Few squamous epithelial cells
a. Are these results of clinical significance?
b. Explain the discrepancy between the chemical and microscopic blood results.
c. What is the probable cause of the granular casts?
a. No, because they are associated with strenuous exercise.
b. The positive blood reaction is from hemoglobinuria or myoglobinuria resulting from participating in a contact sport. The protein is orthostatic.
c. Increased excretion of RTE cell lysosomes in the presence of dehydration.
As supervisor of the urinalysis section, you are reviewing results. State why or why not each of the following results would concern you.
a. The presence of waxy casts and a negative protein in urine from a 6–month-old girl
b. Increased transitional epithelial cells in a specimen obtained following cystoscopy
c. Tyrosine crystals in a specimen with a negative bilirubin test result
d. Cystine crystals in a specimen from a patient diagnosed with gout
e. Cholesterol crystals in urine with a specific gravity greater than 1.040
f. Trichomonas vaginalis in a male urine specimen
g. Amorphous urates and calcium carbonate crystals in a specimen with a pH of 7.0
a. Yes, the waxy casts are probably an artifact such as a diaper fiber. Waxy casts are not associated with negative urine protein.
b. No, this is normal following an invasive procedure.
c. Yes, tyrosine crystals are seen in severe liver disease; therefore, the bilirubin should be positive. The crystals may be an artifact or from a medication.
d. Yes, uric acid crystals may be mistaken for cystine crystals.
e. Yes, radiographic dye crystals associated with a high specific gravity resemble cholesterol crystals.
f. No, Trichomonas is carried asymptomatically by men.
g. No, calcium carbonate crystals are found in alkaline urine; therefore, clumps of amorphous phosphates may be present.
