The Short Cosyntropin Test Revisited: New Normal Reference Range Using LC-MS/MS

Abstract

LC-MS/MS provides cutoff levels for cortisol and 17-OHP after cosyntropin stimulation that are lower than those based on immunoassays, possibly because cross-reactivity between steroid intermediates and cortisol is eliminated. This reduces the number of false-positive tests for AI and false-negative tests for NCCAH.