Bizarre Anca Vasculitis in a Young Woman: Aggressive Treatment is Justified

ANCA vasculitis is a multisystem autoimmune disease characterized by inflammation involving medium and small sized blood vessels. The inflammation is typically caused by self-reacting auto antibodies that bind to neutrophil and make them overly activated. There are 3 subtypes of ANCA mediated vasculitis namely granulomatosis with polyangiitis, microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis. In PR3- ANCA positive vasculitis, the most affected sites are upper respiratory tract, lungs and kidney. A 34-year-old woman presented with cough and dyspnea, and features of AKI among many other symptoms. RT-PCR was negative and pulmonary CT scan showed peripheral ground glass opacities. Kidney Biopsy showed crescentic glomerulonephritis after which COVID-19 infection and SLE were ruled out. PR3-ANCA was positive, and she was diagnosed with granulomatosis with polyangiitis. Her renal and lung function improved eventually after aggressive administration of methylprednisolone followed by cyclophosphamide. Here we present a case of ANCA vasculitis with multisystem involvement, initially COVID-19 confusing the radiological diagnosis.