Concomitant Pheochromocytoma and Primary Aldosteronism: A Case Series and Literature Review

Objective: The detection and management of concomitant pheochromocytoma (PHEO) and primary aldosteronism (PA) is not well understood. Our objectives were to investigate varying presentations and outcomes of cases with coexisting PHEO and PA to provide an approach to its diagnosis and management. Design: Retrospective case series from 2000–2020 at a single institution tertiary center; additional review of previously known cases before 2000 and from the medical literature. Patients and Measurements: Adult patients with concomitant PHEO and PA. Clinical, biochemical, radiologic, and histologic parameters were reviewed. Results: Fifteen patients (53% men, median age 53 years) were diagnosed with concomitant PHEO and PA. The majority presented with hypertension (13, 87%) and hypokalemia (13, 87%), but only 6 (40%) presented with symptoms suggestive of catecholamine excess. All patients with preoperative work-up for catecholamine excess (14, 93%) were found to have elevated plasma or urinary metanephrines/catecholamines above the upper limit of normal. Adrenal vein sampling (AVS) was performed in 9 (60%) patients, where 5 (56%) were diagnosed with bilateral PA, and 4 (44%) with unilateral PA. All patients underwent either unilateral (12, 80%) or bilateral (3, 20%) adrenalectomy to treat their PHEO and/or PA. Postoperative catecholamines and/or catecholamine breakdown products normalized or improved in 13 (87%) patients and were not measured in 2. Recurrence of PHEO was not observed. Six (40%) displayed persistent PA postoperatively, where 4 required long-term mineralocorticoid blockade. Conclusions: Concomitant PHEO and PA is a rare but likely under-reported condition. Hypertension with or without hypokalemia should prompt evaluation for PA, while any indeterminate adrenal mass should be worked up for PHEO. Coexisting disease warrants consideration of AVS to determine the laterality of PA to ensure appropriate management.