Amylase isoenzyme electrophoresis of a serum sample shows a predominant S-type (salivary) isoenzyme with only mildly elevated P-type (pancreatic). This finding would be MOST consistent with which condition?
- A Acute pancreatitis
- B Parotitis (mumps) ✓
- C Macroamylasemia
- D Pancreatic pseudocyst
Correct answer: B. Parotitis (mumps)
Explanation
Amylase exists as two isoenzymes: P-type (pancreatic) and S-type (salivary). In parotitis (e.g., mumps), the S-type isoenzyme is predominantly elevated. Acute pancreatitis elevates P-type isoenzyme. Macroamylasemia causes total amylase elevation (both types bound to immunoglobulin) with urine amylase being low; isoenzyme typing alone does not distinguish it without urinary clearance data. Pancreatic pseudocyst primarily elevates P-type.
Reference: Harper's Illustrated Biochemistry, 32nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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