Steroids and Infection
The steroids secreted by the adrenal cortex are crucial for survival in that they are necessary for the response to a threatening environment. The main adrenal steroids are those such as mineralocorticoid, glucocorticoid and some sex steroids, mainly androgens. This chapter discusses susceptibility of individuals to infections caused by steroids, such as glucocorticoids. Steroid therapy has been suggested for a variety of complications related to human immunodeficiency virus infection, including pneumocystis infections and esophageal and oral ulcerations, because steroid treatment decreases both morbidity and mortality due to Pneumocystis carinii pneumonia. The mechanisms of increased susceptibility to infections induced by steroids are complicated, since steroids affect the function of a wide variety of host cells, including immune cells. The effect of steroids on neutrophils appears to be different than the effects on other leukocytes, since a single dose of steroid induces a significant decrease of circulating monocytes, eosinophils and basophils, but peripheral blood neutrophils increase two or three-fold rather than decrease.