Endocrine Abstracts

Background: The low dose dexamethasone suppression test (LDDST) is an important investigation for suspected Cushing’s syndrome (CS). The traditional definition of normal suppression of serum cortisol to ≤50 nmol/l (0.5 mg 6 hrly × 48 hrs) comes from a time when biochemical auto analysers did not routinely detect very low values. Previous studies reported 5.1–8.3% of patients with Cushing’s disease (CD) suppressed to <50 nmol/l at 48 hrs. Many clin...