Primary bilateral macronodular adrenal hyperplasia presenting as resistant hypertension with bilateral adrenal masses: a case report.

Introduction: Bilateral adrenal incidentalomas are uncommon and may be associated with autonomous cortisol secretions. One important etiology is primary bilateral macronodular adrenal hyperplasia (PBMAH), a rare cause of adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome, which may present without typical Cushingoid features. We describe a patient with ACTH-independent Cushing's syndrome due to bilateral adrenal hyperplasia, who achieved clinical improvement after unilateral adrenalectomy. This case highlights the role of unilateral adrenalectomy as a functional treatment option in PBMAH. Case Presentation: A 59-year-old man presented with resistant hypertension, bilateral leg edema, and proximal muscle weakness, without typical Cushingoid features. Biochemical evaluation confirmed autonomous cortisol secretion, and computed tomography revealed multiple bilateral adrenal masses. Adrenal venous sampling (AVS) demonstrated left-sided dominant cortisol production, leading to laparoscopic left adrenalectomy. Histopathology confirmed macronodular adrenal hyperplasia, and the patient experienced postoperative improvement in both hypertension and glycemic control. Discussion: PBMAH often presents as bilateral adrenal enlargement with cortisol excess, and AVS plays a role in determining functional lateralization in selected patients. Because adrenal size strongly correlates with cortisol secretion, imaging and AVS together help refine surgical decision making. While unilateral adrenalectomy offers favorable outcomes, recurrence rates vary widely, highlighting the need for continued surveillance. Conclusion: For patients with ACTH-independent Cushing's syndrome and bilateral adrenal masses, AVS-guided unilateral adrenalectomy provides a targeted treatment strategy that controls cortisol excess while reducing the risk of permanent adrenal insufficiency.