Primary bilateral macronodular adrenal hyperplasia (PBMAH): from rare to common cause of Cushing syndrome in clinical practice.

Primary Bilateral Macronodular Adrenal Hyperplasia (PBMAH) is considered a rare cause of Cushing syndrome (CS). Despite progress in understanding the pathogenesis, clinical evaluation of the disease and optimal treatment remain relevant. Data were retrieved from institutional/hospital databases. The first group of PBMAH patients comprised 34 cases from a total of 634 adrenalectomies (including 166 CS cases) performed 2009-2015. The second group included 51 patients from 356 adrenalectomies (including 160 CS cases) conducted 2016-2023. Follow-up results are available for 79 patients. PBMAH is an increasingly recognized cause of adrenal CS (21% and 32% in consequent groups). The age of patients was 53.4 ± 7.1 years (range 39-71), with a female prevalence of 77.6%. Patients predominantly exhibited mild CS, accompanied by arterial hypertension, obesity, hyperglycemia, and osteoporosis. We found a high percentage of coexisting primary aldosteronism in both groups (44.1% and 37.3%). All patients, after confirmation of CS, ACTH independence, and imaging visualization, proceeded to unilateral laparoscopic adrenalectomy. Follow-up demonstrated normalization of serum cortisol and clinical improvement in all patients. We detected 4 cases (4.7%) of laboratory recurrence of CS; two of these patients underwent contralateral adrenal resection (both acquired adrenal insufficiency), while the other two continued treatment with blockage of discovered aberrant cortical receptors (using β-blockers and octreotide). PBMAH is not a rare adrenal disease, accounting one-quarter of all operated CS patients. Laparoscopic adrenalectomy of the larger gland leads to long-term remission in most patients and does not result in permanent adrenal insufficiency. Primary aldosteronism is an underestimated condition in PBMAH patients.