Case of Cyclic Cushing's Disease with Improvement of Psoriatic Skin Lesions During a Period of Hypercortisolemia.

Cushing's syndrome (CS) is known to involve periodic cortisol secretion in some patients. It has also been demonstrated that resolution of cortisol hypersecretion in CS may cause autoimmune-related disease to become apparent. At least 3 cases of psoriasis that became apparent after resolution of hypercortisolism in CS have been reported. We describe a 45-year-old man with cyclic Cushing's disease in whom psoriasis vulgaris, an autoimmune-related disease, was ameliorated during a period of hypercortisolemia. He had complained of intermittent sensations of "whole-body swelling" and improvement of his psoriatic skin lesions, which lasted 2 to 3 weeks at 2- to 3-month intervals over several years. During a 2-week hospitalization for endocrine investigations, an episode of hypercortisolemia appeared unexpectedly. During this time period, the peak serum cortisol level reached 75.7 µg/mL (adrenocorticotropic hormone level, 585 pg/mL) and 24-hour urinary free cortisol reached 10 500 µg/day. A diagnosis of Cushing's disease was made based on a markedly elevated urinary free cortisol level, an adequate increase in adrenocorticotropic hormone level in response to corticotropin-releasing hormone stimulation, and the presence of a giant pituitary tumor with a maximum diameter of approximately 4 cm. Interestingly, during this time period, there was a marked improvement in the psoriatic skin lesions and whole-body swelling sensations.