Acute intestinal pseudo-obstruction by pheochromocytoma: A case report with review of literature

Introduction: Pheochromocytomas are rare tumors of the adrenal gland. Intestinal pseudo-obstruction is a very rare presentation of a functioning catecholamine-secreting tumor. We present a case of intestinal pseudoobstruction due to a large functioning pheochromocytoma. Case report: A 29-year-old female presented with abdominal distension, pain, nausea, and vomiting with constipation for 3 weeks. She was hypertensive and diabetic and was on multiple medications. She reported frequent spells of severe headaches, palpitations, night sweats, and a 17 kg weight loss over 6 months. She had pallor, dyspnea, marked abdominal distension, and diminished bowel sounds. Her blood pressure was high at 200/120 mmHg. She had tachycardia (pulse 120 bpm) and tachypnea (35 pm). Serum metanephrine levels were significantly elevated, measuring 1203 pg/ml. Abdominal CT showed a heterogeneous, hyper-vascular mass near the upper pole of the left kidney, measuring 10.75 cm x 8.72 cm. Open left adrenalectomy was performed through an anterior subcostal approach to remove the tumor with the left adrenal gland. Histopathological examinations were consistent with pheochromocytoma. Discussion: Some authors documented the correlation between tumor size and metabolic activity of catecholamine-secreting tumors with intestinal pseudo-obstruction by paralytic ileus. This case corresponds with these findings, with a tumor mass of 350 g and a serum metanephrine level of 1203 pg/ml. Conclusion: Although it is extremely rare, functioning pheochomocytoma could be a cause of instestinal obstruction or pseudo-obstruction.