GLASSY LUNGS, DRUGS AND MELENIC RUNS, A CASE REPORT

ABSTRACT

CASE A 73-year-old male with a history of prostate cancer, hypertension and hyperthyroidism presented with one week of worsening dyspnea, productive cough and pleurisy. He also endorsed new orthopnea and melena over the last three days. Home medications included abiraterone, prednisone, methimazole and amlodipine. On admission, vitals were notable for tachycardia, tachypnea and hypoxia (82% on room air and 90% on 3L by nasal canula (NC)). Initials labs showed WBC count 17.4, Hemoglobin 7.1, proBNP 256, two negative COVID-19 PCR tests, negative respiratory virus panel and normal TSH and PSA. CTPE was negative for pulmonary embolism but showed new diffuse ground glass opacities. The patient was started on broad spectrum antibiotics and IV diuretics for possible pneumonia and new heart failure. However, the patient's respiratory status continued to decline, now requiring 6L by NC. Hemoglobin also continued to drop precipitously. A broad rheumatologic and infectious workup was largely negative with findings notable for a positive ANA, CRP 74, LDH 359 and an undetectable haptoglobin. A urinalysis was positive for protein and blood. At this time, empiric treatment for pneumocystis pneumonia was initiated with a plan for bronchoscopy. The bronchoscopy with bronchoalveolar lavage (BAL) revealed diffuse alveolar hemorrhage (DAH) with studies negative for infection or malignancy. An upper endoscopy did not reveal any gastrointestinal source of bleeding but rather favored a pulmonary source due to some red blood in the esophagus and coffee ground material in the stomach. Given these findings, a diagnosis of “Methimazole induced vasculitis with DAH” was made, a diagnosis of exclusion. The patient was started on pulse steroids for three days and his methimazole was held. By day four, the patient reported improvement and his oxygen was decreased to 2L. He was subsequently discharged on a steroid taper. At his two-week follow-up, the patient had improving respiratory status and repeat labs showed an improved and stable hemoglobin, and normal haptoglobin. IMPACT/DISCUSSION: This case illustrates a rare but life-threatening complication of methimazole use. Common offenders of drug-induced DAH include propylthiouracil, carbimazole and hydralazine. This complication is reported in 15-37% of patients on propylthiouracil but only 0-3% of patients on methimazole. A third of patients with DAH do not present with hemoptysis making this diagnosis challenging. Lab findings can also be largely nonspecific making a thorough history, imaging and interdisciplinary collaboration key in identifying this adverse effect early on to prevent mortality. CONCLUSION: Include drug-induced DAH on the differential for patients presenting with respiratory failure in the setting of new anemia, melena or hemoptysis. Stopping the offending drug and initiating steroids is the treatment of choice. Consider empiric PCP treatment and BAL for patients with severe hypoxia, ground glass opacities and immunosuppression.