Successful Use of Rituximab for Hydralazine-Induced Anti-Neutrophil Cytoplasmic Antibodies-Associated Vasculitis

Hydralazine is a commonly used anti-hypertensive medication. It can, however, contribute to the development of autoimmunity, in the form of drug-induced lupus and anti-neutrophil cytoplasmic antibodies-associated vasculitis. We report a 45-year-old patient with hypertension managed with hydralazine for four years who presented with rapidly progressive glomerulonephritis (RPGN), requiring hemodialysis, and diffuse alveolar hemorrhage (DAH), requiring mechanical ventilation, and extracorporeal membrane oxygenation. The patient's autoantibody profile was consistent with a drug-induced autoimmune process and renal histology revealed focal necrotizing crescentic GN. She was treated with high-dose steroids, plasma exchange and rituximab. DAH resolved and her renal function improved, allowing discontinuation of hemodialysis. This case reveals that rituximab can be successfully used in the setting of hydralazine-induced vasculitis, including critically ill patients with severe DAH and acute kidney injury from RPGN.