Question

a 25 - year - old woman with a recent history of acute hepatitis b infection presents with reddish - blue lesions at different developing stages on her lower extremities, fever, muscle pain, and mild weight loss. physical examination reveals numerous regions of red - purple discoloration affecting the skin of both legs. laboratory test demonstrate an elevated erythrocyte sedimentation rate. urinalysis shows 2 + proteinuria. biopsy of lesional skin demonstrates fibrinoid necrosis. which of the following is the most likely diagnosis?

mönckeberg medial sclerosis
henoch - schönlein purpura
polyarteritis nodosa
wegeners granulomatosis

Explanation:

• Mönckeberg medial sclerosis: Characterized by calcification of the media of muscular arteries, typically in older individuals, and not associated with the symptoms like fever, muscle pain, proteinuria, and fibrinoid necrosis described here.
• Henoch - Schönlein purpura: Usually seen in children, often preceded by an upper respiratory infection. It is an IgA - mediated small - vessel vasculitis. While it can cause purpura and renal involvement (proteinuria), the association with acute hepatitis B is more strongly linked to another condition.
• Polyarteritis nodosa: Can be associated with hepatitis B infection. Features include constitutional symptoms (fever, weight loss), skin manifestations (livedo reticularis, nodules, purpura - like lesions at different stages), and renal involvement (proteinuria). Histologically, fibrinoid necrosis of medium - sized arteries is a key finding.
• Wegener's granulomatosis: Involves the upper and lower respiratory tracts (nasal ulcers, sinusitis, pulmonary nodules) and the kidneys. It is associated with c - ANCA (antineutrophil cytoplasmic antibodies) and not typically with hepatitis B.

Answer:

Polyarteritis nodosa