Metyrapone test with adrenocorticotrophic levels. Separating primary from secondary adrenal insufficiency
L. I. Dolman, G. Nolan and W. Jubiz
Basal plasma adrenocorticotrophic hormone (ACTH) and cortisol
concentrations as well as plasma ACTH and 11-deoxycortisol responses to the
administration of a single dose of metyrapone were evaluated in 104
patients with intact pituitary-adrenal axis, in 20 patients with secondary
adrenal insufficiency, and in seven patients with primary adrenal
insufficiency. In patients with primary adrenal insufficiency, baseline
ACTH levels were high. Following metyrapone administration,
11-deoxycortisol concentrations were low and ACTH levels did not change. In
patients with secondary adrenal insufficiency, baseline plasma ACTH levels
were normal, but neither 11-deoxycortisol nor ACTH levels increased in
response to metyrapone. The metyrapone test is not only useful to screen
for adrenal insufficiency, it is also useful to differentiate a primary
from a secondary cause.
