A Case of Functioning Paraganglioma Mimicking Anaphylactic Shock - A Case Report

Paraganglioma is a tumor originating from the extra-adrenal chromaffin cells, and functional paraganglioma causes paroxysmal hypertension, headache and tachycardia, due to excess excretion of catecholamine. However, rarely, ARDS, acute myocardial infarction, heart failure, arrhythmia, and pulmonary edema are also seen in patients with paraganglioma and clinical manifestations are depending on the patient’s intravascular volume status. Seventy one-years-old male was presented with hypotension and pulmonary edema after intravenous midazolam injection during colonoscopy under conscious sedation. The patient was initially suspected with anaphylactic shock, due to midazolam injection. However, later, he was diagnosed with paraganglioma, and blood pressure was successfully controlled with alpha adrenergic blockade. We suggest that when we encounter heart failure, pulmonary edema and shock of unknown origin, pheochromocytoma must be taken into consideration.