A 24-year-old woman with a recent history of acute hepatitis B infection presents with reddish-blue lesions 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 tests demonstrate positive P-ANCA and an elevated erythrocyte sedimentation rate. Urinalysis shows 2+ proteinuria. Biopsy of lesional skin is shown in the figure. Which of the following is the most likely diagnosis?
- Benign arteriosclerosis
- Fibromuscular dysplasia
- Henoch-Schönlein purpura
- Mönckeberg medial sclerosis
- Polyarteritis nodosa