Rethinking dexamethasone suppression test thresholds in the era of precision steroid profiling

This commentary critically appraises a recent study by Rotolo et al. that highlights diagnostic discrepancies between immunoassays and LC-MS/MS in the 1 mg overnight dexamethasone suppression test (DST). While the study provides compelling evidence for method-specific thresholds, we identify key limitations: the lack of an independent gold standard, incomplete steroid profiling, absence of dexamethasone quantification, and retrospective design. We propose integrating latent-class models, expanded steroid panels, and pharmacokinetic data to refine DST accuracy. Prospective, multicentre harmonization efforts are essential to validate adjusted cut-offs and ensure diagnostic precision across platforms and patient populations.