Double Trouble: A Case Report of Hydralazine-Induced Vasculitis and Lupus.

We present a rare case of hydralazine-induced antineutrophil cytoplasmic antibody (ANCA) vasculitis and lupus, characterized by the simultaneous and severe involvement of multiple organ systems. Following outpatient hydralazine dose escalation, a 77-year-old woman developed hypoxic respiratory failure secondary to diffuse alveolar hemorrhage, acute kidney injury with crescentic glomerulonephritis, and pancytopenia. Serologic testing revealed positive antinuclear antibody (ANA), dsDNA, anti-histone antibody, and P-ANCA, supporting the diagnosis of drug-induced autoimmune syndrome. This case highlights the risk for severe multi-organ dysfunction in drug-induced lupus and vasculitis, emphasizing the need for vigilance in recognizing such complications.