Effect of Antimicrobial and Antineoplastic Drugs Alone and in Combination on the Phagocytic and Candidacidal Function of Human Polymorphonuclear Leucocytes

Four antimicrobial and three antineoplastic drugs were screened for their effects on phagocytosis and killing of Candida albicans blastospores by human neutrophil polymorphonuclear leucocytes. Amphotericin B caused significant impairment of both phagocytosis and killing, but cefuroxime and ketoconazole had no effect. Tobramycin did not affect phagocytosis, but impaired killing. Methotrexate, prednisolone and vinblastine all caused significant impairment of phagocytosis, but did not affect killing. Combinations of these seven drugs, such as are used in the treatment of acute lymphoblastic leukaemia in childhood, were also shown to inhibit phagocytosis, although no additive effects were detected. None of the drug combinations tested affected killing.