[Short term effects of ketoconazole in Cushing's syndrome]

The effects of Ketoconazole (600 mg/day) were evaluated in 10 patients with Cushing's syndrome during a mean period of 4.5 weeks (range 1-12). The urinary free cortisol excretion (UFC) decreased by 21 +/- 15% (mean +/- SEM) (p less than 0.01) on day 1; 54 +/- 8% (p less than 0.0001) on day 2; 60 +/- 15% (p less than 0.0001) on day 3 and 87 +/- 3% (p less than 0.0001) on day 8 compared to baseline. Salivary cortisol at 0800 h decreased similarly. On day 3, 7 patients showed normal UFC values and on day 8, only 1 patient, with the ectopic ACTH syndrome, had persistent hypercortisolism. The cortisol decrease was associated with an increase in desoxycorticosterone values (p less than 0.01) and a decrease in dehydroepiandrosterone sulfate (p less than 0.001), delta 4 androstenedione (p less than 0.05) and testosterone (p less than 0.05). No significant variations were observed in ACTH, 11 desoxycortisol, aldosterone, plasma renin activity, corticosteroid-binding globulin and sex hormone-binding globulin. Side effects were few: mild clinical adrenal insufficiency (n = 5), oedema (n = 3) and reversible hepatic toxicity (n = 1). We conclude that Ketoconazole is an effective inhibitor of cortisol and androgens synthesis. It is well tolerated, rapidly effective and its efficacy persists unchanged for at least one month in all forms of Cushing's syndromes. For these reasons Ketoconazole may be a valuable drug for preoperative treatment of Cushing's syndrome.