ACTH Stimulation Test

Indication

Diagnose adrenal insufficiency.

Procedure

  1. Administer 250 μg iv corticotropin.
  2. Measure serum cortisol at 30 or 60 min.

Interpretation

Peak cortisol < 500 nmol/L indicates adrenal insufficiency. For secondary adrenal insufficiency: specificity 95% & sensitivity 57%. Garber 2003

Caveats

Increased CBG Decreased CBG
Estrogen containing OCPs Nephrotic syndrome
Liver disease
Immediate post-operative period

Alternatives