Medical Technologist Test Clinical Chemistry 1 — Questions and Answers
Question 1: Which enzyme is the MOST sensitive and specific marker for acute myocardial infarction?
- AST
- LDH
- Troponin I or T (Correct answer)
- CK-MB
Correct answer: Troponin I or T
Cardiac troponins (I and T) are the gold-standard biomarkers for myocardial injury due to their high cardiac specificity and sensitivity.
Question 2: What is the normal fasting blood glucose reference range for adults?
- 50–70 mg/dL
- 70–99 mg/dL (Correct answer)
- 100–125 mg/dL
- 126–140 mg/dL
Correct answer: 70–99 mg/dL
A fasting plasma glucose of 70–99 mg/dL is considered normal; 100–125 mg/dL indicates prediabetes.
Question 3: Elevated serum amylase and lipase are characteristic of which condition?
- Hepatitis
- Acute pancreatitis (Correct answer)
- Renal failure
- Myocardial infarction
Correct answer: Acute pancreatitis
Both amylase and lipase are pancreatic enzymes that rise significantly during acute pancreatitis; lipase is more specific.
Question 4: Which electrolyte imbalance is MOST likely in a patient with prolonged vomiting?
- Hyperkalemia
- Hyperchloremia
- Hypokalemic metabolic alkalosis (Correct answer)
- Hypernatremia
Correct answer: Hypokalemic metabolic alkalosis
Prolonged vomiting causes loss of HCl from the stomach, leading to hypokalemia and metabolic alkalosis.
Question 5: What does an elevated BUN-to-creatinine ratio (>20:1) typically indicate?
- Intrinsic renal failure
- Prerenal azotemia (Correct answer)
- Postrenal obstruction
- Chronic kidney disease
Correct answer: Prerenal azotemia
A BUN:Cr ratio >20:1 suggests prerenal causes (dehydration, low cardiac output) where urea reabsorption is disproportionately high.
Question 6: Hemoglobin A1c (HbA1c) reflects average blood glucose over approximately how many weeks?
- 2–4 weeks
- 6–8 weeks
- 10–12 weeks (Correct answer)
- 16–20 weeks
Correct answer: 10–12 weeks
HbA1c reflects average glycemia over approximately 8–12 weeks, corresponding to the lifespan of a red blood cell.
Medical Technologist Test Clinical Chemistry 1
Which enzyme is the MOST sensitive and specific marker for acute myocardial infarction?