Opportunistic infections in endogenous Cushing's syndrome.

The cases of 6 patients with endogenous Cushing's syndrome and opportunistic infections were studied, and compared with those of 17 similar patients reported in the literature. Cushing's syndrome was caused by ectopic adrenocorticotrophic hormone production or adrenal tumors in most patients, and hypercortisolism was extreme. Four infectious processes were preponderant: Cryptococcosis, aspergillosis, nocardiosis, or Pneumocystis carinii pneumonia occurred in 21 patients. Signs and symptoms of infection were often masked by the hypercortisolism. Morning plasma cortisol levels correlated with the infection type (rank-order Spearman correlation coefficient = 0.78, p less than 0.01): Levels of less than 70 micrograms/dL or greater than 121 micrograms/dL were associated with cryptococcosis or pneumocystis, respectively, by discriminant analysis. Of the 9 patients who survived their infection, 8 had evidence that cortisol production was reduced to near normal. In contrast, all 14 patients died in whom cortisol production went uncontrolled. In patients with hypercortisolism from endogenous Cushing's syndrome (especially of nonpituitary origin), opportunistic infections should be anticipated and prompt control of cortisol overproduction should be initiated.