Chapter 6 Microscopic Examination of Urine

Question 1

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

Answer 1

A

Question 2

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

Answer 2

D

Question 3

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

Answer 3

C

Question 4

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

Answer 4

C

Question 5

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

Answer 5

A

Question 6

Initial screening of the urine sediment is performed using
an objective power of:
A. 4×
B. 10×
C. 40×
D. 100×

Answer 6

B

Question 7

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

Answer 7

C

Question 8

Which of the following are reported as number per lpf?
A. RBCs
B. WBCs
C. Crystals
D. Casts

Answer 8

D

Question 9

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

Answer 9

C

Question 10

Nuclear detail can be enhanced by:
A. Prussian blue
B. Toluidine blue
C. Acetic acid
D. Both B and C

Answer 10

D

Question 11

Which of the following lipids is/are stained by Sudan III?
A. Cholesterol
B. Neutral fats
C. Triglycerides
D. Both B and C

Answer 11

D

Question 12

Which of the following lipids is/are capable of polarizing
light?
A. Cholesterol
B. Neutral fats
C. Triglycerides
D. Both A and B

Answer 12

A

Question 13

The purpose of the Hansel stain is to identify:
A. Neutrophils
B. Renal tubular cells
C. Eosinophils
D. Monocytes

Answer 13

C

Question 14

Crenated RBCs are seen in urine that is:
A. Hyposthenuric
B. Hypersthenuric
C. Highly acidic
D. Highly alkaline

Answer 14

B

Question 15

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

Answer 15

C

Question 16

A finding of dysmorphic RBCs is indicative of:
A. Glomerular bleeding
B. Renal calculi
C. Traumatic injury
D. Coagulation disorders

Answer 16

A

Question 17

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

Answer 17

D

Question 18

Mononuclear leukocytes are sometimes mistaken for:
A. Yeast cells
B. Squamous epithelial cells
C. Pollen grains
D. Renal tubular cells

Answer 18

D

Question 19

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

Answer 19

B

Question 20

Transitional epithelial cells are sloughed from the:
A. Collecting duct
B. Vagina
C. Bladder
D. Proximal convoluted tubule

Answer 20

C

Question 21

The largest cells in the urine sediment are:
A. Squamous epithelial cells
B. Urothelial epithelial cells
C. Cuboidal epithelial cells
D. Columnar epithelial cells

Answer 21

A

Question 22

A clinically significant squamous epithelial cell is the:
A. Cuboidal cell
B. Clue cell
C. Caudate cell
D. Columnar cell

Answer 22

B

Question 23

Forms of transitional epithelial cells include all of the
following except:
A. Spherical
B. Caudate
C. Convoluted
D. Polyhedral

Answer 23

C

Question 24

Increased transitional cells are indicative of:
A. Catheterization
B. Malignancy
C. Pyelonephritis
D. Both A and B

Answer 24

D

Question 25

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

Answer 25

D

Question 26

Following an episode of hemoglobinuria, RTE cells may
contain:
A. Bilirubin
B. Hemosiderin granules
C. Porphobilinogen
D. Myoglobin

Answer 26

B

Question 27

The predecessor of the oval fat body is the:
A. Histiocyte
B. Urothelial cell
C. Monocyte
D. Renal tubular cell

Answer 27

D

Question 28

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

Answer 28

A

Question 29

The finding of yeast cells in the urine is commonly associated
with:
A. Cystitis
B. Diabetes mellitus
C. Pyelonephritis
D. Liver disorders

Answer 29

B

Question 30

The primary component of urinary mucus is:
A. Bence Jones protein
B. Microalbumin
C. Uromodulin
D. Orthostatic protein

Answer 30

C

Question 31

The majority of casts are formed in the:
A. Proximal convoluted tubules
B. Ascending loop of Henle
C. Distal convoluted tubules
D. Collecting ducts

Answer 31

C

Question 32

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

Answer 32

D

Question 33

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

Answer 33

D

Question 34

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

Answer 34

B

Question 35

WBC casts are primarily associated with:
A. Pyelonephritis
B. Cystitis
C. Glomerulonephritis
D. Viral infections

Answer 35

A

Question 36

The shape of the RTE cell associated with renal tubular
epithelial casts is primarily:
A. Elongated
B. Cuboidal
C. Round
D. Columnar

Answer 36

C

Question 37

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

Answer 37

A

Question 38

The presence of fatty casts is associated with:
A. Nephrotic syndrome
B. Crush injuries
C. Diabetes mellitus
D. All of the above

Answer 38

D

Question 39

Nonpathogenic granular casts contain:
A. Cellular lysosomes
B. Degenerated cells
C. Protein aggregates
D. Gram-positive cocci

Answer 39

A

Question 40

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

Answer 40

C

Question 41

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

Answer 41

D

Question 42

All of the following contribute to urinary crystals formation
except:
A. Protein concentration
B. pH
C. Solute concentration
D. Temperature

Answer 42

A

Question 43

The most valuable initial aid for identifying crystals in a
urine specimen is:
A. pH
B. Solubility
C. Staining
D. Polarized microscopy

Answer 43

A

Question 44

Crystals associated with severe liver disease include all of
the following except:
A. Bilirubin
B. Leucine
C. Cystine
D. Tyrosine

Answer 44

C

Question 45

All of the following crystals routinely polarize except:
A. Uric acid
B. Cholesterol
C. Radiographic dye
D. Cystine

Answer 45

D

Question 46

Casts and fibers can usually be differentiated using:
A. Solubility characteristics
B. Patient history
C. Polarized light
D. Fluorescent light

Answer 46

C

Question 47

Match the following crystals seen in acidic urine with their
description/identifying characteristics:
\_\_\_\_ Amorphous urates 
\_\_\_\_ Uric acid 
\_\_\_\_ Calcium oxalate monohydrate
\_\_\_\_ Calcium oxalate dihydrate

1. Envelopes
2. Thin needles
3. Yellow-brown, whetstone
4. Pink sediment
5. Ovoid

Answer 47

4, 3, 5, 1

Question 48

Match the following crystals seen in alkaline urine with
their description/identifying characteristics:
____ Triple phosphate
____ Amorphous phosphate
____ Calcium phosphate
____ Ammonium biurate
____ Calcium carbonate

1. Yellow granules
2. Thin prisms
3. “Coffin lids”
4. Dumbbell shape
5. White precipitate
6. Thorny apple

Answer 48

3 5 2 6 4

Question 49

Match the following abnormal crystals with their
description/identifying characteristics:
\_\_\_\_ Cystine 
\_\_\_\_ Tyrosine 
\_\_\_\_ Cholesterol 
\_\_\_\_ Leucine 
\_\_\_\_ Ampicillin 
\_\_\_\_ Radiographic dye
\_\_\_\_ Bilirubin 

1. Bundles following refrigeration
2. Highly alkaline pH
3. Bright yellow clumps
4. Hexagonal plates
5. Flat plates, high specific gravity
6. Concentric circles, radial striations
7. Notched corners
8. Fine needles seen in liver disease

Answer 49

4 8 7 6 1 5 3

Question 50

Match the following types of microscopy with their
descriptions:
\_\_\_\_ Bright-field 
\_\_\_\_ Phase 
\_\_\_\_ Polarized 
\_\_\_\_ Dark-field 
\_\_\_\_Fluorescent 
\_\_\_\_Interference 

1. Indirect light is reflected off the object
2. Objects split light into two beams
3. Low refractive index objects may be overlooked
4. Three-dimensional images
5. Forms halo of light around object
6. Detects electrons contrast emitted from objects
7. Detects specific wavelengths
   of light emitted from objects

Answer 50

3 5 2 1 7 4

Question 51

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?

Answer 51

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.

Question 52

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?

Answer 52

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.

Question 53

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.

Answer 53

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.

Question 54

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?

Answer 54

a. The patient is taking a pigmented medication, such as phenazopyridine.
b. Yes.
c. Ask what medications the patient is taking.
d. Ampicillin

Question 55

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?

Answer 55

a. Calcium oxalate
b. Monohydrate and dihydrate calcium oxalate
c. Oval: monohydrate; envelope: dihydrate
d. Monohydrate

Question 56

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?

Answer 56

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.

Question 57

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?

Answer 57

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.

Question 58

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

Answer 58

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.