ODP036 Cortisol Values During the Standard-Dose Cosyntropin Stimulation Test: Personal Experience with Elecsys Cortisol II Assay

BACKGROUND: There has been debate regarding the appropriate cortisol cutoffs during the cosyntropin stimulation test (CST) when the newer cortisol assays are used. Recent studies have recommended cortisol cutoffs lower than previously recommended. We aimed to evaluate the cortisol levels during the standard dose CST in patients evaluated for adrenal insufficiency and found to have a normal HPA axis using the Elecsys ® Cortisol II (Roche Diagnostics)assay. METHODS: This was a retrospective chart review study of adult patients who had the CST performed within an academic ambulatory setting from January 2018 to December 2020. They had ICD-10 codes of pituitary gland disorders in their problem list or diagnoses at the time of data extraction. Only patients with a normal HPA axis were included in the analysis, which was defined based on evaluation by an endocrinologist, restrictive exclusion criteria, and a lack of glucocorticoid administration for at least 6 months after CST. Exclusion criteria included oral glucocorticoid use within 6 months before the CST or 3 months for other routes, albumin < 2.5 g/dL, liver disease, pituitary insult within 6 weeks before the CST, estrogen and opioid use within 3 months before the CST, and pregnancy. The results are reported in the median (range). RESULTS: Out of 305 patients, 63 (20.6) met the study criteria. The median age was 54.7 (27.6-89.1) years; 32 (51%) were females, and 27 (43%) were white. The duration of follow-up after the CST was 13.9 (6.3-43.9) months. Cortisol values at 30- and 60-minutes post-CST were available for 43 (68.2%), and 61 patients (96.8%), respectively. The cortisol levels at 30- and 60-minutes after the CST were 21.7 (15.7-29.1) µg/dL and 24.4 (17.9-35.8) µg/dL, respectively. The lowest cortisol levels at 30 and 60 minutes after the CST for patients with either normal TSH or gonadal axis (n=47) or in whom both axes were normal (n=18) were similar to the entire cohort. CONCLUSION: Our study supports using a lower cortisol cutoff value at 30 minutes after the CST using the Roche Elecsys ® Cortisol II assay. The lowest cortisol level in our cohort was 15.7 ug/dL. However, the same pass criteria cannot be used at 60 minutes. Therefore, it is essential to consider the time of cortisol draw after the CST. Presentation: No date and time listed