Clinical microscopy practice exam categorized by difficulty
Test your knowledge with our Clinical Microscopy Practice Exam categorized by difficulty. Each item comes with a clear explanation to help you understand the correct answer and strengthen your exam skills. Perfect for ASCP MLS and MLT exam prep!
1. Which of the following is a normal finding in a urine sample?
A. Protein
B. Glucose
C. Red blood cells
D. Urea
✅ Answer: D. Urea
Explanation:
Urea is a normal component of urine and is a waste product of protein metabolism. It is excreted in the urine. The presence of protein, glucose, or red blood cells would typically indicate an abnormality.
2. Which test is most commonly used to assess kidney function in a urinalysis?
A. Specific gravity
B. Protein content
C. Microscopic examination
D. Glucose content
✅ Answer: A. Specific gravity
Explanation:
The specific gravity test measures the concentration of solutes in the urine, which helps assess the kidney’s ability to concentrate urine and indicates hydration status or renal function.
3. What is the normal range for urinary pH?
A. 4.0–5.0
B. 5.0–6.5
C. 6.0–7.5
D. 7.0–8.5
✅ Answer: B. 5.0–6.5
Explanation:
The normal urinary pH typically ranges from 5.0 to 6.5, which is slightly acidic. Urinary pH can vary based on diet, hydration, and renal function.
4. Casts that is most commonly associated with acute tubular necrosis?
A. Hyaline casts
B. Red blood cell casts
C. Granular casts
D. Waxy casts
✅ Answer: C. Granular casts
Explanation:
Granular casts are often seen in acute tubular necrosis (ATN) and indicate renal tubular damage. They result from the degeneration of cells and protein within the renal tubules.
5. Which of the following would be considered a pathological finding in urine sediment?
A. Squamous epithelial cells
B. Calcium oxalate crystals
C. WBCs greater than 5 per high power field
D. Uric acid crystals
✅ Answer: C. WBCs greater than 5 per high power field
Explanation:
An increased number of white blood cells (WBCs) in urine sediment is abnormal and suggests infection or inflammation in the urinary tract.
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6. It is a condition commonly associated with a positive urine dipstick result for glucose.
A. Diabetes mellitus
B. Dehydration
C. Hypertension
D. Nephrotic syndrome
✅ Answer: A. Diabetes mellitus
Explanation:
Diabetes mellitus is commonly associated with glycosuria, the presence of glucose in the urine, due to high blood glucose levels that exceed the renal threshold for glucose reabsorption.
7. What type of crystal is commonly associated with uric acid stones?
A. Ammonium biurate
B. Calcium oxalate
C. Uric acid
D. Triple phosphate
✅ Answer: C. Uric acid
Explanation:
Uric acid crystals are commonly found in urine and are often associated with uric acid stones in patients with gout or hyperuricemia.
8. What is the most common type of bacteria seen in urine culture in patients with urinary tract infections (UTIs)?
A. Escherichia coli
B. Streptococcus pyogenes
C. Staphylococcus aureus
D. Enterococcus faecalis
✅ Answer: A. Escherichia coli
Explanation:
Escherichia coli (E. coli) is the most common causative organism for urinary tract infections (UTIs), accounting for the majority of infections.
9. Which of the following is the primary cause of proteinuria in patients with nephrotic syndrome?
A. Tubular dysfunction
B. Glomerular damage
C. Increased filtration of albumin
D. Increased renal blood flow
✅ Answer: B. Glomerular damage
Explanation:
Nephrotic syndrome is primarily caused by glomerular damage, which leads to the leakage of large proteins (like albumin) into the urine. This is due to damage to the glomerular basement membrane and the podocytes.
10. Which type of urine crystal is most commonly associated with kidney stones in patients with hypercalciuria?
A. Uric acid crystals
B. Calcium oxalate crystals
C. Ammonium biurate crystals
D. Cystine crystals
✅ Answer: B. Calcium oxalate crystals
Explanation:
Calcium oxalate crystals are most commonly associated with kidney stones in patients with hypercalciuria (excess calcium in the urine). These crystals can form due to high levels of calcium and oxalate in the urine.
11. Which of the following microscopic findings is associated with acute pyelonephritis?
A. Hyaline casts
B. White blood cell casts
C. Granular casts
D. Epithelial casts
✅ Answer: B. White blood cell casts
Explanation:
White blood cell (WBC) casts are commonly seen in acute pyelonephritis, an infection of the renal parenchyma, and they indicate inflammation in the renal tubules.
12. Which of the following urinary pH values is commonly seen in patients with uric acid stones?
A. Acidic (pH < 5.0)
B. Neutral (pH = 7.0)
C. Alkaline (pH > 7.5)
D. Slightly acidic (pH = 6.0–6.5)
✅ Answer: A. Acidic (pH < 5.0)
Explanation:
Uric acid stones tend to form in an acidic urinary environment, typically when the pH is below 5.0. Increasing the urinary pH can help prevent the formation of uric acid stones.
13. Which of the following is a common cause of hematuria (presence of blood in urine) without proteinuria?
A. Glomerulonephritis
B. Nephrotic syndrome
C. Urinary tract infection
D. Kidney stones
✅ Answer: D. Kidney stones
Explanation:
Kidney stones (renal calculi) often cause hematuria due to mechanical irritation or trauma to the urinary tract. The presence of blood without significant protein in the urine is a typical finding.
14. The presence of what substance in the urine can suggest rhabdomyolysis?
A. Bilirubin
B. Myoglobin
C. Urobilinogen
D. Ketones
✅ Answer: B. Myoglobin
Explanation:
Myoglobin is released from damaged skeletal muscle during rhabdomyolysis and can be detected in the urine. It can lead to acute kidney injury when filtered by the kidneys.
15. Which of the following is the most appropriate technique for identifying Trichomonas vaginalis in urine?
A. Wet mount microscopy
B. Gram stain
C. Acid-fast stain
D. Immunofluorescence
✅ Answer: A. Wet mount microscopy
Explanation:
Trichomonas vaginalis can be detected in urine using a wet mount preparation under the microscope, where the motility of the organism can be observed.
16. Which type of crystals is commonly associated with cystinuria?
A. Calcium oxalate
B. Uric acid
C. Cystine
D. Ammonium biurate
✅ Answer: C. Cystine
Explanation:
Cystine crystals are characteristic of cystinuria, a genetic disorder in which cystine, a sulfur-containing amino acid, forms crystals in the urine due to impaired renal reabsorption.
17. Which of the following is most commonly seen in urine sediment in patients with minimal change disease?
A. Red blood cell casts
B. Hyaline casts
C. Waxy casts
D. Fatty casts
✅ Answer: D. Fatty casts
Explanation:
In minimal change disease, fatty casts are often seen due to the lipiduria (fat in the urine) that occurs when there is significant proteinuria. These casts are formed when lipids are trapped in the renal tubules and are excreted in the urine
18. Which of the following findings in urine sediment suggests acute tubular necrosis (ATN)?Add Your Heading Text Here
A. Hyaline casts
B. Granular casts
C. Waxy casts
D. White blood cell casts
✅ Answer: B. Granular casts
Explanation:
Granular casts are a hallmark of acute tubular necrosis (ATN). They form when degenerating renal tubular cells or protein debris are trapped in the casts, indicating renal tubular injury.
19. Which of the following is the most common finding in the urine of patients with protein-losing enteropathy?Add Your Heading Text Here
A. Uric acid crystals
B. Hyaline casts
C. Oval fat bodies
D. Calcium oxalate crystals
✅ Answer: C. Oval fat bodies
Explanation:
Oval fat bodies are fat-laden epithelial cells that may be seen in the urine of patients with protein-losing enteropathy (a condition where the gastrointestinal tract loses protein). These cells are sloughed from the renal tubules due to lipiduria.
20. Which of the following types of crystals is commonly seen in the urine of patients with hypercalciuria?
A. Uric acid
B. Ammonium biurate
C. Calcium oxalate
D. Cystine
✅ Answer: C. Calcium oxalate
Explanation:
Calcium oxalate crystals are commonly found in the urine of patients with hypercalciuria (excess calcium in the urine). These crystals form in an environment with high calcium levels and low pH.
21. Which of the following is the most sensitive test for diagnosing hematuria in the absence of visible blood in the urine?
A. Microscopic examination of urine sediment
B. Urine dipstick for blood
C. Urinary protein excretion
D. Urine culture
✅ Answer: B. Urine dipstick for blood
Explanation:
The urine dipstick for blood is highly sensitive for detecting hematuria (presence of red blood cells in urine) and can identify microscopic hematuria, which may not be visible to the naked eye.
22. What would be the expected finding in the urine of a patient with acute interstitial nephritis?
A. Proteinuria without casts
B. WBC casts with proteinuria
C. Hyaline casts with hematuria
D. Granular casts with hematuria
✅ Answer: B. WBC casts with proteinuria
Explanation:
In acute interstitial nephritis, there is inflammation of the renal interstitial tissue, which can lead to the formation of white blood cell (WBC) casts in the urine. Proteinuria is also often present.
23. Which of the following conditions is most commonly associated with pyuria (pus cells in urine)?
A. Renal calculi
B. Urinary tract infection
C. Glomerulonephritis
D. Nephrotic syndrome
✅ Answer: B. Urinary tract infection
Explanation:
Pyuria, the presence of white blood cells (WBCs) in urine, is most commonly associated with urinary tract infections (UTIs). The WBCs are a result of inflammation in the urinary tract due to infection.
24. Which of the following urine crystals are commonly associated with alkaline urine and urinary tract infections caused by urease-producing organisms?
A. Uric acid
B. Calcium phosphate
C. Struvite
D. Cystine
✅ Answer: C. Struvite
Explanation:
Struvite crystals (also known as triple phosphate crystals) form in alkaline urine, particularly in patients with urinary tract infections (UTIs) caused by urease-producing organisms such as Proteus and Klebsiella. These crystals are often associated with renal calculi.
25. A urine specimen exhibits a red-brown color, is positive for blood on the reagent strip, but shows no red blood cells on microscopic examination. What is the most likely explanation for these findings?
A. Hematuria
B. Myoglobinuria
C. Hemoglobinuria
D. Porphobilinogen presence
✅ Answer: B. Myoglobinuria
Explanation: A positive reagent strip for blood with no red blood cells microscopically suggests the presence of free hemoglobin or myoglobin.
To differentiate:
Hemoglobinuria often follows intravascular hemolysis and may show signs of hemolytic anemia.
Myoglobinuria, often due to muscle trauma or rhabdomyolysis, presents with red-brown urine and no RBCs.
Resources:
- Henry’s Clinical Diagnosis and Management by Laboratory Methods (23rd Edition)
- Clinical Laboratory Science Review by Robert Harr (6th Edition)
- Urinalysis and Body Fluids by Susan King Strasinger & Marjorie Schaub Di Lorenzo (6th Edition)
- ASCP BOC Study Guide – Clinical Laboratory Certification Examinations (6th Edition)
- Rodak’s Hematology: Clinical Principles and Applications (6th Edition)
- CLSI Guidelines (Clinical and Laboratory Standards Institute)
- LabCE and MediaLab Online Practice Exams