A 45-year-old alcoholic man develops severe epigastric pain radiating to the back. Contrast CT reveals peripancreatic fat stranding with scattered small bright foci within the inflamed omental fat. The biochemical process generating these radiopaque foci is:

• A Deposition of calcium phosphate in dead tissue despite normal serum calcium
• B Binding of free fatty acids to calcium, forming insoluble calcium soaps ✓
• C Precipitation of urate crystals from supersaturated extracellular fluid
• D Calcium deposition secondary to chronic renal failure with phosphate retention

Explanation

Fat necrosis in acute pancreatitis occurs when released pancreatic lipases digest triglycerides in adipocytes into free fatty acids, which combine with calcium to form chalky-white insoluble calcium soaps (saponification). These deposits are radiopaque and can lower serum calcium enough to cause hypocalcemia. Option A describes dystrophic calcification elsewhere in injured tissue, option C describes gouty tophi, and option D describes the mechanism of metastatic calcification in secondary hyperparathyroidism.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.