A Rare Presentation of Hydralazine-Induced Lupus in the Setting of Pericarditis With Concomitant Angioedema.

Drug-induced lupus (DIL) usually presents after starting a medication known to induce DIL. However unusual presentations are rare, as such, our patient presented with initial signs and symptoms of pericarditis. Once treated as such, he progressively declined to symptoms of angioedema and worsening cardiopulmonary status. On first admission, the patient presented with chest pain that was worsened by laying down and improved by sitting up. CT Angiography (CTA) showed mild pericardial effusion, and EKG showed diffuse ST elevation, both suggestive of pericarditis, for which the patient was discharged on colchicine. The patient was readmitted one day later with swelling of the neck and tongue. The patient was re-evaluated, tested for autoantibodies, and found a positive antinuclear antibody (ANA) suggesting a diagnosis of lupus, most likely due to hydralazine. We report a rare presentation of drug-induced lupus initially presenting with pericarditis which evolved into worsening angioedema which has not been reported in the literature thus far. Pericarditis and angioedema may be the initial presentation for a patient with drug-induced lupus. Antinuclear and anti-histone antibodies are highly sensitive and specific respectfully for drug-induced lupus. Early diagnosis and time-appropriate discontinuation of the offending agent for patients can be life-saving.