SAT-422 - Successful Empiric Adrenalectomy in CKD Patient with Hypercortisolism, Hyperaldosteronism, and Unilateral Adrenal Adenoma

Background:
Concurrent mild autonomous cortisol secretion (MACS) and primary aldosteronism (PA) occur in up to 21.9% of PA cases. Current US guidelines recommend adrenal venous sampling (AVS) to localize aldosterone secretion prior to adrenalectomy, while ACTH-independent hypercortisolism guidelines allow empiric surgery for a unilateral adenoma. AVS requires significant IV contrast and may be high-risk in advanced chronic kidney disease (CKD). We present a patient with PA, MACS, and stage 4 CKD managed with empiric adrenalectomy instead of AVS.

Case Presentation:
A 68-year-old male with resistant hypertension and hypokalemia was diagnosed with PA in 2020 (Aldosterone/Renin Ratio 228 (ng/dL)/(ng/mL/hr)), with initial imaging showing bilateral adrenal adenomas on CT. AVS was not completed due to loss to follow-up. Despite medical therapy, he progressed to stage 4 CKD by 2025 with eGFR as low as 17. Reevaluation confirmed PA and newly identified ACTH-independent hypercortisolism via dexamethasone suppression testing (3.1 mcg/dL), late-night salivary cortisol (0.25, 0.22, 0.17 mcg/dL, with upper limit normal of 0.09), and low ACTH ( < 5 ng/L). Repeat non-contrast CT showed a solitary 1.4 cm right adrenal adenoma. Given high renal risk from AVS due to his CKD, multidisciplinary consensus with endocrine surgery and interventional radiology favored empiric right adrenalectomy. Surgery was uncomplicated, with pathology confirming adrenal adenoma. Postoperatively, spironolactone and potassium supplementation were stopped. The patient reported improved energy levels, blood sugar, and blood pressure control, with systolic blood pressure improving 160–180 to 120–130 mmHg. Transient hyperkalemia (peak 6.4 mmol/L at 2 weeks, resolving to 5.6 mmol/L without intervention) occurred as has been reported after mineralocorticoid withdrawal. Renal function remained stable. No postoperative glucocorticoids were required.

Discussion:
This case highlights an alternative to AVS in patients with advanced CKD. In the setting of cortisol co-secretion and a unilateral adrenal adenoma, empiric adrenalectomy was pursued with expectation of MACS remission and improvement in PA. Postoperative clinical and biochemical improvements support this proposal. Additionally, surgical treatment of PA may help slow CKD progression, though longer follow-up is needed to confirm. In conclusion, empiric adrenalectomy may be a reasonable option in select patients with dual pathology and contraindications to AVS.

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