Hepatitis B virus infection associated with polyarteritis nodosa and microscopic polyangiitis.

We reported a unique case with the coexistence of classic and cutaneous polyarteritis nodosa (PAN), and microscopic polyangiitis (MPA) in hepatitis virus-associated vasculitis. A 77-year-old Asian man presented with extremity weakness and weight loss found to have bilateral foot drop and rash on his hands and legs. Labs reveal positive for hepatitis B core antibody and perinuclear-antineutrophil cytoplasmic antibody (p-ANCA), decreased C3 and C4 levels. Skin biopsy of rash shows medium vessel vasculitis suggesting PAN. Interestingly, renal biopsy showed features of necrotising medium-sized arteritis consistent with PAN and focal crescentic glomerulonephritis consistent with MPA. The patient was treated with 1 g of solumedrol daily for 3 days, followed by oral steroids and cyclophosphamide treatment for vasculitis, and entecavir for chronic hepatitis B infection, resulting in resolution of symptoms. The patient has not had a relapse at 6 months.