Treatment of severe psychosis due to ectopic Cushing's syndrome

Severe psychosis in patients with Cushing's syndrome is rare and generally difficult to treat. We report a 46-yr-old woman suffering from Cushing's syndrome caused by an inoperable ACTH-producing lung carcinoma. She was initially treated with chemotherapy and radiotherapy. Six months later she presented with severe psychosis. Laboratory findings revealed a severe hypokaliemia and metabolic alkalosis, which was caused by extremely high serum ACTH (788 ng/l) and cortisol (4.2 mumol/l). She was unresponsive to treatment with conventional antipsychotic drugs; she was therefore sedated and intubated. Treatment was started iv with etomidate, which blocks the cortisol synthesis, and orally by nasogastric tube with mifepristone, which competes with cortisol for binding to their receptors. To counteract adrenal insufficiency, she received corticosteroids. After 5 days there was a normalization of the ACTH, cortisol levels, and the metabolic disorders. After discontinuing etomidate she was extubated; there were no signs of psychosis observed. Computed tomography (CT) scan of the brain showed no metastasis, however CT scan of the abdomen showed liver metastasis and bilateral adrenal enlargement. Unfortunately, the clinical situation worsened and the patient died due to progression of the metastasis. This case report demonstrates the efficacy of a treatment of mifepristone with etomidate in a patient with an ectopic ACTH-producing Cushing's syndrome.