A biopsy of a skin lesion from a patient with polyarteritis nodosa shows bright eosinophilic, fibrin-like deposition in the walls of small arteries, along with necrosis of the smooth muscle cells. Which term best describes this vascular pattern of injury?
- A Fibrinoid necrosis ✓
- B Caseous necrosis
- C Fat necrosis
- D Gummatous necrosis
Correct answer: A. Fibrinoid necrosis
Explanation
Fibrinoid necrosis is characterized by the deposition of immune complexes and fibrin within the vessel wall, appearing as bright eosinophilic material. It is typical of vasculitides like polyarteritis nodosa and malignant hypertension. Caseous necrosis is seen in tuberculosis and shows amorphous granular debris. Fat necrosis occurs in acute pancreatitis. Gummatous necrosis is a feature of tertiary syphilis.
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.