Muscle weakness as a presenting symptom in ANCA-associated vasculitis

Abstract

Muscle weakness is rarely a presenting symptom of anti-neutrophil cytoplasmic antibody (ANCA)-as-sociated vasculitis (AAV), although the disease frequently involves the lungs, skin, neurons, and kid-neys. Here we describe a case of AAV presenting with muscle weakness in which only muscle biopsycould confirm the diagnosis. The literature review, including three similar cases, suggested that pa-tients with ANCA-associated muscle vasculitis likely had myalgia, normal levels of creatine kinase,pulmonary fibrosis, rheumatoid factor, and muscle edema on MRI.