Hormone secretion in alcohol-induced pseudo-Cushing's syndrome. Differential diagnosis with Cushing disease

Abstract

The clinical and biochemical characteristics of alcohol-induced pseudo-Cushing''s syndrome were described in 2 patients with signs and symptoms of Cushing''s syndrome and slight disturbances in liver function. An insufficient suppression of plasma cortisol to the overnight administration of 1 mg of dexamethasone was accompanied by an absent diurnal rhythm of plasma cortisol and an increased cortisol secretion rate. The plasma cortisol levels at 0800 normalized during hospital admission (i.e., alcohol withdrawal) at the same rate or parallel with the serum .gamma.-glutamyl transferase concentration. A normal increase of plasma cortisol, ACTH and growth hormone in response to an insulin-induced hypoglycemia was not compatible with the diagnosis of Cushing''s syndrome. The result of a differential diagnostic test with metyrapone was compatible with the presence of Cushing''s disease. An erroneous diagnosis of Cushing''s disease can be easily made in patients with alcohol-induced pseudo-Cushing''s syndrome.