Hydralazine-induced antineutrophil cytoplasmic antibody-associated vasculitis with pulmonary–renal syndrome: a case report

BACKGROUND: Hydralazine is a common vasodilator which has been used for the treatment of hypertension and heart failure. Hydralazine can induce antineutrophil cytoplasmic antibody-associated vasculitis due to its auto-immunogenic capability and one of the very rare presentations is pulmonary–renal syndrome. CASE PRESENTATION: We report a case of a 64-year-old African American woman, who presented to our emergency room with shortness of breath, orthopnea, paroxysmal nocturnal dyspnea, leg swelling, fatigue, loss of appetite, cough with clear sputum, and lightheadedness. On admission, she developed acute hypoxic respiratory failure requiring intubation and acute renal failure requiring hemodialysis. A serologic workup was positive for antineutrophil cytoplasmic antibody, antinuclear antibody, anti-histone, anti-cardiolipin IgM, and anti-double-stranded DNA antibodies. A renal biopsy was done due to persistent deterioration in kidney function and demonstrated classic crescentic (pauci-immune) glomerulonephritis. Hydralazine was empirically discontinued early in the admission and she was started on corticosteroids and cyclophosphamide following biopsy results. She was clinically stable but remained dependent on hemodialysis after discharge. CONCLUSION: Hydralazine-induced antineutrophil cytoplasmic antibody-associated vasculitis with pulmonary–renal syndrome is a rare occurrence. In the setting of hydralazine use, multiple positive antigens, and multisystem involvement, clinicians should consider this rare condition requiring prompt cessation of offending drug, early evaluation with biopsy, and contemplate empiric immunosuppressive therapy while biopsy confirmation is pending.