The adrenal response to exogenous adrenocorticotrophin in patients with infections due to Neisseria meningitidis.

The adrenal response to a soluble form of beta1-24-corticotropin (tetracosactrin [ACTH]: 250 microgram administered intramuscularly) was studied in 28 patients with meningitis due to Neisseria meningitidis (21 with petechiae and seven without) and in six patients with Salmonella typhi bacteremia. Six normal subjects also were tested for adrenal responsiveness at four different times of the day (8 A.M., 12 noon, 4 P.M., and 10 P.M.) and served as controls. The results showed that, whatever the time of testing, patients with meningococcal infections and typhoid fever had unstimulated (basal) levels of plasma cortisol above the 99% confidence limits for the mean unstimulated cortisol levels for the normal subjects. Furthermore, although patients with meningitis without petechiae and subjects with S. typhi bacteremia responded to ACTH stimulation in a manner similar to that of the normal subjects, most subjects with meningitis with petechiae did not have increased levels of plasma cortisol after treatment with ACTH. This lack of response could not be ascribed entirely to the higher basal levels of plasma cortisol in these patients. Patients with meningitis associated with petechiae may have a relatively decreased adrenal response to stimulation with exogenous ACTH.