Context: Serum free cortisol (SFF) responses to cosyntropin simulation test (CST) may more accurately assess adrenal function than total cortisol (TF).
Objective: The objective of the study was to evaluate the diagnostic utility of SFF responses during a 250-μg CST.
Design: We recruited healthy volunteers (HV; n = 27), patients with primary and secondary adrenal insufficiency (n = 19 and n = 24, respectively), and subjects with Child-Pugh class A cirrhosis (CH; n = 15).