title: Obstructive sleep apnea presenting as pseudopheochromocytoma.
abstract: A 39-year-old man with a history of poorly controlled hypertension presented with a 2-year history of fatigue, daytime somnolence, and intermittent episodes of diaphoresis and palpitations. Episodes were self-limiting, lasting approximately 5-10 minutes and occurred several times per month, most notably at night. Laboratory evaluation was significant for elevated 24-h urinary catecholamine levels, suggestive of pheochromocytoma. However, thorough imaging failed to identify a catecholamine-secreting tumor. Subsequent polysomnography revealed severe obstructive sleep apnea, with an apnea-hypopnea index of 112 events/h. After one month of continuous positive airway pressure therapy, the patient experienced resolution of his presenting symptoms, improved blood pressure control and normalization of his urinary catecholamine levels. This case highlights sleep disordered breathing as a potentially reversible cause of pseudopheochromocytoma.
authors.affiliation: Department of Medicine, Critical Care and Sleep Medicine, Walter Reed Army Medical Center Washington, DC. USA.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Cheezum
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Lettieri
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000652:urine; D000328:Adult; D002395:Catecholamines / Q000652:urine; D045422:Continuous Positive Airway Pressure / Q000379:methods; D003937:Diagnosis, Differential; D005221:Fatigue / Q000150:complications / Q000628:therapy; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000628:therapy; D008297:Male; D009765:Obesity / Q000150:complications; D010673:Pheochromocytoma / Q000150:complications / Q000175:diagnosis* / Q000652:urine; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000175:diagnosis* / Q000628:therapy
chemical_list: D002395:Catecholamines
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