LAUSR

Abstract Background Pheochromocytoma is a rare catecholamine-secreting tumor of the adrenal chromaffin cells. Historically, these tumors have been described by the classic triad of paroxysmal tachycardia, diaphoresis and headaches in the setting of uncontrolled hypertension. However, most patients do not manifest with these typical symptoms; usually uncontrolled hypertension is their only sign. Rarely pheochromocytoma may present with dramatic multiorgan damage. Case A 31-year-old male presented with progressive epigastric pain of two weeks duration. He had associated nausea, non-bloody diarrhea, and unintended weightloss of eight pounds. His only medical history was a remote isolated episode of pancreatitis. Physical exam was positive for hypertension,with a blood pressure of 223/142 mm Hg, inappropriate somnolence and moderate epigastric tenderness. Lab work revealed leukocytosis (12.2x109 /µL, n<10), normocytic anemia (Hb 7.8g/dL, n=14-17), thrombocytopenia (100 x109/L, n=150-450) deranged renal function (BUN 124 mg/dL, n< 20, creatinine 21.6mg/dL, n< 1.3), proteinuria (>= 500 mg/dL, n<20), mild hematuria with metabolic acidosis (pH of 7.25 and anion gap of 20). Noncontrast CT of the abdomen demonstrated acute colitis, and a left adrenal mass measuring 4.4 x 4.4 x 4.5 cm. Blood pressure was controlled using IV Nicardipine infusion and he was prepared for hemodialysis. His anemia worsened, and blood work favored microangiopathic hemolytic anemia. His stay was further complicated by acute respiratory failure warranting intubation, during a session of hemodialysis. Chest radiograph suggested possible ARDS or pulmonary edema as cause for respiratory distress. An evaluation for secondary causes of hypertension suggested pheochromocytoma. While they could be elevated due to the stress of the situation, his plasma metanephrines (153 pg/ml, n<57) and normetanephrines (1197 pg/ml, n<148) were significantly elevated to suggest the diagnosis of pheochromocytoma presenting as hypertensive emergency. He underwent an MRI of the abdomen which further characterized the adrenal lesion. Once he was stabilized, he was transferred to a tertiary center for evaluation of tumor resection. Conclusion This is a very rare case of pheochromocytoma in a previously healthy individual, presenting with malignant hypertension, hemolytic anemia and renal failure. This case also highlights the clinical relevance of plasma metanephrines and plasma catecholamines, as well as the image phenotype when diagnosing pheochromocytoma in a patient with this process. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.