S5802 Cryoglobulinemia as an Unusual Manifestation of Untreated Hepatitis C

Introduction: With the advent of highly effective direct-acting anti-viral agents (DAAs) for Hepatitis C (HCV) infection, chronic HCV infection and its complications have sharply declined in the past decade. Extra-hepatic complications of chronic HCV, including dermatologic manifestations, are thus rarely seen nowadays. Here, we present a case of severe cryoglobulinemic vasculitis in a middle-aged woman with a history of longstanding, untreated chronic HCV. Case Description/Methods: A 59-year-old woman with a history of smoking and untreated HCV presented to the Emergency Department for leg pain and worsening skin lesions in both her lower extremities. She initially had erythematous lesions scattered on the lower extremities which then progressed into a necrotic appearance without purulence or drainage. On exam, there were numerous ulcerative lesions of varying sizes on both lower extremities. She reported a diagnosis of HCV 20 years ago, without any treatment, and HCV viral load was positive. Laboratory testing was also notable for normal renal function but significant proteinuria. Computed tomography of the lower extremities did not show evidence of necrotizing fasciitis but noted bilateral subcutaneous edema. Rheumatology and dermatology were consulted due to concern for possible HCV related cryoglobulinemic vasculitis (CV). Serological testing showed a low C4, normal C3, and elevated rheumatoid factor consistent with CV. Skin biopsy by dermatology showed fibrinoid necrosis and intravascular fibrinoid material consistent with a small vessel vasculitis, confirming the diagnosis of CV. During this admission, the patient had leukocytosis with concern for acute infection. Therefore, initiation of rituximab for the CV was deferred and she was started on prednisone in the interim. She is currently being followed in rheumatology clinic for rituximab induction and hepatology clinic for HCV anti-viral therapy. Discussion: CV is a small vessel vasculitis that often involves organs including the skin and kidneys as seen in this patient. There are a few subtypes of CV of which types II and III are associated with HCV. Treatment includes rituximab for CV, with DAAs for underlying HCV, with severe cases needing plasmapheresis. Our patient was initially treated with steroids due to concern for infection, but is now being induced with rituximab. We present this case to highlight an unusual and severe case of extra-hepatic manifestations of untreated HCV.