Friday Night Acute Kidney Injury: Chest Infection Masking Antineutrophil Cytoplasmic Antibody Vasculitis.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) includes a group of autoimmune disorders resulting in the production of autoantibodies to neutrophil proteins (leukocyte proteins, proteinase 3 (PR3)-ANCA or myeloperoxidase proteins (MPO)-ANCA). There are three subtypes of AAV based on ANCA serotypes: PR3+ AAV, MPO+ AAV, and ANCA+. These rare disorders present with a wide spectrum of symptoms with involvement of multiple organs, including the heart, kidneys, eyes, ears, brain, spinal cord, nerves, and musculoskeletal system, making them difficult to diagnose promptly. This impacts the prognosis of AAV, as involvement of major organs can increase recurrence rates and lead to a poor prognosis, while timely diagnosis can lead to full recovery. Treatment options mainly involve immunosuppression with steroids, rituximab, methotrexate, and cyclophosphamide to maintain remission. We discuss a case of granulomatosis with polyangiitis in an adult male. We believe this report will help highlight timely diagnosis and interventions, overall improving the prognosis of patients.