Clinical Enzymology and Organ Function Tests (LFT, RFT, Cardiac/Pancreatic Enzymes) MCQs

Biochemistry · 21 free questions with answers & explanations.

1. A 58-year-old man presents with crushing chest pain 6 hours ago. Serial cardiac enzymes are ordered. Which isoenzyme pattern on serum electrophoresis is MOST specific for myocardial infarction?
2. In a patient with obstructive jaundice, which pattern of liver function tests is MOST characteristic?
3. A 45-year-old alcoholic presents with severe epigastric pain. Serum amylase is 850 U/L and serum lipase is 1200 U/L. Which statement about these enzymes in acute pancreatitis is CORRECT?
4. A patient with suspected renal disease has the following results: serum creatinine 3.2 mg/dL, BUN 48 mg/dL, BUN:creatinine ratio 15:1. Which interpretation is MOST accurate?
5. Gamma-glutamyl transferase (GGT) is elevated in a patient. Which combination would MOST specifically indicate alcohol-related liver disease?
6. A 58-year-old man presents 10 hours after onset of chest pain. Serum troponin I is markedly elevated. His total CK is 850 U/L (normal <200), and CK-MB is 170 U/L. What percentage of CK-MB to total CK confirms myocardial infarction?
7. In obstructive jaundice, which of the following enzyme patterns is MOST characteristic?
8. A 45-year-old alcoholic has GGT 320 U/L (normal <55), ALP 130 U/L (normal <120), and normal bilirubin. The BEST interpretation is:
9. Serum amylase and lipase are both elevated in acute pancreatitis. Which statement CORRECTLY distinguishes lipase from amylase as a marker?
10. Which isoenzyme of LDH has the HIGHEST concentration in the myocardium and shows flip pattern in myocardial infarction?
11. A patient with suspected Wilson's disease has serum ceruloplasmin of 0.08 g/L (normal 0.2–0.6 g/L). Which enzyme activity provides a DIRECT functional assessment of copper status in this context?
12. A 58-year-old man presents with crushing chest pain for 3 hours. Troponin I is markedly elevated. Which isoform of creatine kinase (CK) would be characteristically elevated in this patient, and what is its subunit composition?
13. In obstructive jaundice, which enzyme is MOST specifically elevated due to its induction by biliary stasis and its location on the canalicular membrane of hepatocytes?
14. A patient with acute pancreatitis has serum amylase 800 U/L (normal <100 U/L). Which isoform of amylase is elevated, and which organ typically contributes MORE to total serum amylase in healthy individuals?
15. De Ritis ratio (AST:ALT) >2 in a patient with liver disease is MOST suggestive of which condition?
16. A 45-year-old patient undergoing renal function assessment has a serum creatinine of 1.8 mg/dL. The creatinine clearance is 48 mL/min. Which biochemical principle makes creatinine a useful but imperfect glomerular filtration marker?
17. A 58-year-old man presents 12 hours after onset of severe chest pain. Serum troponin I is markedly elevated. Regarding cardiac troponin I (cTnI), which statement best describes its diagnostic superiority over CK-MB?
18. In a patient with obstructive jaundice, which pattern of liver enzyme elevation is most characteristic?
19. A 45-year-old man with acute pancreatitis has serum amylase 1800 U/L. Which of the following best distinguishes serum lipase from serum amylase as a marker in this condition?
20. A 70-year-old man with known prostate carcinoma has a markedly elevated serum acid phosphatase with a disproportionate rise in prostatic fraction. Which isoenzyme is specifically measured to confirm prostatic origin?
21. The AST:ALT ratio (De Ritis ratio) > 2 is characteristic of which hepatic condition?