Carroll, Ty B

Abstract Context Patients with mild autonomous cortisol secretion (MACS) can develop adrenal insufficiency after unilateral adrenalectomy. Objective This work aimed to determine the prevalence, duration, and predictors of adrenal insufficiency, and compare postoperative basal cortisol and cosyntropin stimulation test (CST). Methods In this multicenter retrospective study of patients with MACS, adrenal insufficiency was diagnosed when postoperative basal cortisol was less than 10 µg/dL and/or CST < 18 µg/dL. The results were concordant when both tests met cutoffs. Biochemical (BSS) and clinical severity scores (CSS) were calculated. Results Among 281 patients with MACS (80% women), postoperative adrenal insufficiency was diagnosed in 153 (54.5%) patients. Adrenal insufficiency inversely correlated with age (odds ratio [OR] 0.67 per 10 years; 95% CI, 0.53-0.84). Low basal cortisol and CST were associated with younger age (OR 0.64 per 10 years for both) and higher BSS (OR 1.17 and 1.22, respectively). Basal cortisol and CST were discordant in 22% of patients, and the discordance rate was more common in patients with bilateral nodules (32% vs 19%; P < .001). The median time to adrenal insufficiency recovery was 3.9 months (IQR, 3-5.9 months), with longer duration associated with higher BSS and CSS: 3 months for mild, 4 to 5 months for moderate, and 12 to 14 months for severe BSS and CSS. Conclusion Approximately half of patients with MACS developed postoperative adrenal insufficiency, with 50% recovering by 3.9 months after surgery. BSS correlated with basal cortisol, CST, and duration of adrenal insufficiency. As discordant results were noted in 22%, performing both basal cortisol and CST postoperatively should be considered.

Abstract Disclosure: S.H. Johnson: None. C. Zhang: None. P.T. Hangge: None. T.W. Yen: None. T. Shaik: None. K. Doffek: None. J.W. Findling: None. T.B. Carroll: None. D.B. Evans: None. S. Dream: None. T.S. Wang: None. Background: Secondary adrenal insufficiency (SAI) may occur in patients after unilateral adrenalectomy for adrenal-dependent hypercortisolism (HC) and/or primary aldosteronism (PA). Perioperative protocols include routine glucocorticoid replacement (GR) or selective GR based on postoperative day 1 (POD1) basal cortisol levels or cosyntropin stimulation testing (CST). This study aimed to assess if a POD1 basal cortisol level alone was predictive of an abnormal CST and the need for GR in patients following unilateral adrenalectomy for HC and/or PA. Methods: This is a single institution retrospective review of consecutive unilateral adrenalectomies performed for HC and/or PA from 9/2014-10/2022. Patients were grouped as overt hypercortisolism (OH;n=42), mild autonomous cortisol excretion (MACE;n=70), mixed PA/HC (n=22) or PA (n=73); 22 patients with PA did not have preoperative evaluation for HC. Preoperative morning cortisol after low-dose dexamethasone suppression testing (DST), was used to define MACE (1.8-4.9 µg/dL) and OH (≥5.0). POD1 CST was performed for all patients with HC and prior to 2021, all patients with PA. SAI was defined as basal cortisol ≤5 or stimulated ≤14 (≤18 before 4/2017). Receiver operating characteristic (ROC) curves and sensitivity analyses were performed to assess the sensitivity (SN) and specificity (SP) of cutoffs within the range of observed basal cortisol levels in predicting an abnormal CST and need for GR. Results: Of 207 patients, 152 had POD1 CST (93% OH, 96% MACE, 73% PA/HC, 41% PA). Of these, 80 (53%) had SAI (67% OH, 55% MACE, 44% PA/HC, and 33% PA). Of the 10 patients with PA and SAI, 5 did not have preoperative testing for HC. Overall, 81 patients were discharged on GR. Median (interquartile range [IQR]) duration of GR was 246 (127,557), 55 (38,207), 74 (16,185), and 26 (15,36) days in patients with OH, MACE, PA/HC, and PA, respectively. At a median follow-up of 142 days (IQR 42,617), 12 patients (5 OH, 6 MACE, 1 PA/HC) remained on GR. The SN/SP of a basal cortisol ≤10 in predicting GR was 92%/77% in patients with OH and 94%/73% of patients with MACE. Compared to initiation of GR based on basal cortisol ≤10, CST identified 4 patients with SAI in the combined OH and MACE cohorts who would not have received GR, and 11 in the combined cohort who did not require GR. For patients with PA and PA/HC, a basal cortisol ≤10 had SN of 100% and SP of 85% and 67%, respectively. The optimal basal cortisol for predicting SAI in patients with PA/HC was ≤5 (SN,SP 100%). Area under the curve for all ROC curves was >0.9. Conclusion: These results demonstrate that in patients who underwent unilateral adrenalectomy for HC, PA, or mixed PA/HC, POD1 CST improved identification of patients at risk for SAI compared to basal cortisol levels alone. While basal cortisol levels alone may be considered in patients with PA or mixed HC/PA, all other patients with HC should have POD1 CST to determine need for postoperative GR. Presentation: Friday, June 16, 2023

Abstract Context The normal cortisol response 30 or 60 minutes after cosyntropin (ACTH[1–24]) is considered to be ≥18 μg/dL (500 nmol/L). This threshold is based on older serum cortisol assays. Specific monoclonal antibody immunoassays or LC-MS/MS may have lower thresholds for a normal response. Objective To calculate serum cortisol cutoff values for adrenocorticotropic hormone (ACTH) stimulation testing with newer specific cortisol assays. Methods Retrospective analysis of ACTH stimulation tests performed in ambulatory and hospitalized patients suspected of adrenal insufficiency (AI). Serum samples were assayed for cortisol in parallel using Elecsys I and Elecsys II immunoassays, and when volume was available, by Access immunoassay and LC-MS/MS. Results A total of 110 patients were evaluated. Using 18 μg/dL as the cortisol cutoff after ACTH stimulation, 14.5%, 29%, 22.4%, and 32% of patients had a biochemical diagnosis of AI using the Elecsys I, Elecsys II, Access, and LC-MS/MS assays, respectively. Deming regressions of serum cortisol were used to calculate new cortisol cutoffs based on the Elecsys I cutoff of 18 μg/dL. For 30-minute values, new cutoffs were 14.6 μg/dL for Elecsys II, 14.8 μg/dL for Access, and 14.5 μg/dL for LC-MS/MS. Baseline cortisol <2 μg/dL was predictive of subnormal stimulated cortisol values. Conclusion To reduce false positive ACTH stimulation testing, we recommend a new serum cortisol cutoff of 14 to 15 μg/dL depending on the assay used (instead of the historical value of 18 μg/dL with older polyclonal antibody assays). Clinicians should be aware of the new cutoffs for the assays available to them when evaluating patients for AI.