The in-vitro influence of ceftazidime on host defence mechanisms.

The effects of ceftazidime, a new third generation cephalosporin, on host defence mechanisms, was investigated in vitro. No significant alteration of polymorphonuclear leukocyte chemotactic, phagocytic, or chemiluminescent responses were found. Granulocyte adherence to nylon fibre columns was increased by 10 mg/l or more of ceftazidime. Lymphocyte DNA synthesis was slightly decreased by high concentrations of ceftazidime, though not by therapeutic concentrations. Ceftazidime was found to stimulate the release of increased amounts of chemotaxis and phagocytosis-stimulating factors from Escherichia coli and Pseudomonas aeruginosa when bacteria were exposed to subminimal inhibitory concentrations of the antibiotic during active growth phases.