(1219) A Unique Case of Diffuse Alveolar Hemorrhage Related to Hydralazine

Introduction: Hydralazine-induced ANCA associated vasculitis (AAV) with pulmonary involvement is rare. There is limited literature describing the pathology, most of which are case reports. Still, recognizing the diagnosis is key to proper management. This case report details a challenging presentation of hydralazine AAV resulting in diffuse alveolar hemorrhage (DAH) and highlights key diagnostic features.

Description: A 64-year-old female with a medical history of end-stage renal disease secondary to IgA nephropathy and hypertension presented with chief complaint of productive cough on-going for one month associated with intermittent blood-tinged sputum. Chest computed tomography revealed diffuse patchy bilateral ground glass opacities suggestive of pneumonia. Broad-spectrum antibiotics were initiated but there was no clinical improvement. She required 2 units of packed red blood cells after admission to maintain hemoglobin > 7 g/dl. Bronchoscopy was performed with serial Bronchoalveolar Lavage (BAL) aliquots consistent with diffuse alveolar hemorrhage. BAL cytology showed abundant RBCs and macrophages. Laboratory tests revealed positive MPO-ANCA and PR-3-ANCA, negative C-ANCA, negative P-ANCA, elevated anti-histone antibody levels (10.3 IU/mL), Chromatin antibody > 8, low complement C3 level 72 mg/dl, a high titer of antinuclear antibodies (>1:1280) and elevated serum aspergillus galactomannan antigen. High dose steroids along with voriconazole were initiated leading to improvement in patient’s clinical status.

Discussion: DAH secondary to hydralazine induced AAV is rare and the time between initiation of the drug and vasculitis onset can range from 5 months to 6 years. Recognizing the diagnosis is key to prompt discontinuation of the offending agent and initiation of immunosuppressive therapy to mitigate ongoing inflammation and prevent further injury. It is associated with positive anti-MPO antibodies and anti-PR3 antibodies. The presence of positive anti-histone antibodies and low complement levels can help distinguish it from primary AAV. It primarily affects kidneys but, in our case, pulmonary manifestation dominated the clinical picture. In our patient, concomitant invasive aspergillosis also played a role in DAH which makes this case incredibly unique.