Perioperative variation in phagocytic activity against Candida albicans measured by a flow-cytometric assay in cardiovascular-surgery patients.

Candidiasis is an opportunistic fungal infection that frequently occurs following modifications of host defenses. Major surgery can be responsible for such alterations, and therefore it increases the risk of fungal infection. The purpose of this study was to evaluate the perioperative impairment of leukocyte function in patients after cardiovascular surgery by measuring the phagocytic activity against Candida albicans by a flow-cytometric method. The average postsurgical decrease in phagocytosis in our patients was 11.4%. By univariate analysis, three factors, all related to antibiotic therapy, were significantly associated with an important decrease in phagocytosis; the use of antimicrobial therapy before surgery, the number of different antibiotics taken, and the length of antibiotic treatment. The results of our study showed that the use of antibiotics in patients undergoing cardiovascular surgery alters the normal phagocytic activity of the host immune system against C. albicans and that flow cytometry is a rapid and simple technique that helps in early identification of patients at high risk for Candida infections. The mechanisms by which surgery and antibiotics decrease phagocytosis remain to be elucidated.