Case Presentation: A 25-year-old female at 29 weeks gestation presented to the inpatient obstetrics service with hypertension, gestational diabetes and concerns for preeclampsia. Physical exam was significant for a blood pressure of 151/93 and a gravid abdomen. Ultrasound followed by abdominal MRI showed a right suprarenal lesion. Hospital medicine was consulted for recommendations regarding work up of hypertension and the suprarenal lesion. Amlodipine and labetalol were started. Testing showed elevated levels of catecholamines, with serum free normetanephrines of 26 nmol/L (normal <0.50) and urine norepinephrine of 772 ug/dL (normal 0-100 ug/dL) suggestive of a pheochromocytoma. Due to persistent hypertension and flushing, the patient was admitted to the ICU for initiation of alpha-adrenergic blockade with phenoxybenzamine. Labetalol was continued while phenoxybenzamine was titrated up. Amlodipine was stopped. Within 48 hours of medication adjustments complete alpha-adrenergic blockade was achieved with reduction in tachycardia and improved blood pressure measurements. The patient was discharged home with plans for a staged Cesarean delivery followed by removal of the suprarenal mass. At 34 weeks and 5 days gestation, she underwent primary Cesarean delivery of a healthy girl followed by right adrenalectomy. She tolerated the procedure and was titrated off of her antihypertensive medications postoperatively. Pathology revealed a well-circumscribed mass that did not extend past the capsule of the adrenal gland consistent with pheochromocytoma.
Discussion: Pheochromocytoma occurs in only 0.007% of pregnancies. Undiagnosed pheochromocytomas in pregnancy are associated with 40-50% maternal and fetal mortality. Diagnosis is confounded by clinical similarities to preeclampsia. Elevated 24 hour fractionated urine catecholamines or metanephrines are very sensitive and specific for pheochromocytoma. MRI is the preferred imaging modality for tumor localization in pregnancy. Initial medical management in preparation for surgical intervention is treatment with phenoxybenzamine, a selective alpha-adrenergic blocker. Labetalol is also an appropriate first line medication in pregnancy. Isolated beta-blockade (i.e. propranolol) should be avoided, due to the increased risk of unopposed alpha-adrenergic activity. In pregnant patients the timing and safety of adrenalectomy is controversial and depends on the viability and gestational age of the fetus. Prior to 24 weeks gestation a laparoscopic adrenalectomy can safely be performed. After 24 weeks gestation, the patient is typically medically managed until combination Cesarean section and laparoscopic adrenalectomy can be performed.
Conclusions: Hypertension is a common diagnosis encountered by a hospitalist. While pheochromocytoma is a known secondary cause of hypertension, its presence in pregnancy is rare. This case illustrates the diagnostic work-up and management decisions involved in caring for this complex condition.
To cite this abstract:Breger K, Thompson J, Chadaga S. Pheochromocytoma in Pregnancy: Evaluation and Management. Abstract published at Hospital Medicine 2015, March 29-April 1, National Harbor, Md. Abstract 464. Journal of Hospital Medicine. 2015; 10 (suppl 2). https://www.shmabstracts.com/abstract/pheochromocytoma-in-pregnancy-evaluation-and-management/. Accessed July 20, 2019.