DeLozier OM, Dream SY, Findling JW, et al. - Postoperative day 1 cosyntropin stimulation testing (POD1-CST) identifies hypercortisolism (HC) individuals at risk for adrenal insufficiency (AI) after unilateral adrenalectomy (UA), allowing for selective glucocorticoid replacement (GR). One-quarter of individuals with overt hypercortisolism (OH) and nearly half of those with mild autonomous cortisol excess (MACE) can avoid GR after UA. If concurrent HC has been ruled out, PA patients do not need to be evaluated for AI.

• A prospective database identified 108 patients who underwent UA from 9/2014 to 10/2020 for MACE (n = 47), overt hypercortisolism (OH) (n = 27), PA (n = 22), and concurrent PA/HC (n = 12); all had preoperative HC evaluation.

• Fifty-one patients (47%) had an aberrant POD1-CST; 54 patients (50%) were released on GR (27 MACE, 20 OH, 1 PA, 6 PA/HC).

• The median duration of GR was 6.0 months for OH, 2.1 months for MACE, 1 month for PA, and 0.8 months for PA/HC.

• Overall, GR was not required by 26% (n = 7) of OH patients and 43% (n = 20) of MACE patients.

• POD1-CST was normal in two (2%) of the OH patients, but they developed AI few weeks later, necessitating GR.

• AI did not endanger anyone's life.