BACKGROUND
This report presents a life-threatening case of pancytopenia and disseminated intravascular coagulation (DIC) related to hydralazine-associated, drug-induced lupus and drug-induced anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (DIL/DIV) overlap syndrome. Diagnostic and therapeutic challenges are discussed.
CASE REPORT
A 52-year-old man presented with severe pancytopenia, fever, and possible pneumonia. He developed altered mental status, severe DIC with gastrointestinal bleeds requiring large amount of blood product transfusions, acute respiratory failure requiring intubation, acute kidney injury needing hemodialysis, acute liver injury, possible acute pancreatitis, and hypotension. Extensive investigations revealed no source of infection. Further workup was consistent with hydralazine-induced DIL/DIV overlap spectrum. Hydralazine was stopped. He was treated with steroids daily and intravenous cyclophosphamide every 2 weeks (7 doses). However, pancytopenia did not improve. Therefore, on the seventh day after the second cyclophosphamide dose, a repeat bone marrow biopsy was performed to guide further therapy. He later recovered, and hemodialysis was discontinued. A total of 104 units of blood products were transfused. After discharge, steroids were tapered off and mycophenolate mofetil was given for 2 years. In August 2026 (6 years after initial presentation), he was doing well, with normal complete blood count, stable renal function, and normal urinalysis. Array genotyping revealed NAT2 diplotype *5.002/*6.002, indicating slow acetylation (poor metabolizer status).
CONCLUSIONS
This case supports, rather than proves, hydralazine-induced DIL/DIV overlap as the leading explanation for life-threatening pancytopenia with overt DIC. It highlights diagnostic and therapeutic challenges and eventual recovery after hydralazine withdrawal and immunosuppressive treatment. Salient features include the detailed autoimmune workup, severe presentation, coexistence of pancytopenia and overt DIC, and extended follow-up within a rare clinical context.

Keywords: Disseminated Intravascular Coagulation; Hydralazine; Lupus Erythematosus, Systemic; Pancytopenia; Vasculitis