At autopsy of an emaciated adult who died of chronic starvation, the femoral bone marrow is grossly gelatinous and translucent instead of yellow and greasy. Microscopy shows the normal fat cells replaced by mucoid ground substance. This change results from replacement of marrow fat by material rich in:
- A Hyaluronic acid containing ground substance ✓
- B Collagen fibers laid down by fibroblasts
- C Amyloid deposited from serum proteins
- D Glycogen accumulated in histiocytes
Correct answer: A. Hyaluronic acid containing ground substance
Explanation
Serous atrophy of fat, also called gelatinous transformation of bone marrow, is a hallmark of severe caloric deprivation seen in starvation and anorexia nervosa. The adipocytes shrink and are replaced by mucoid ground substance rich in hyaluronic acid, giving the marrow its jelly-like appearance. It is a reversible depletion change, not fibrosis, amyloid deposition, or glycogen storage, which distinguishes it from the other listed processes.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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