Influence of adjunct azithromycin on the mortality of experimental Pseudomonas aeruginosa sepsis.

The aim of this study was to determine the in vivo influence of azithromycin subinhibitory concentrations on mortality in a peritonitis-sepsis model. One hour after an intraperitoneal injection of Pseudomonas aeruginosa, mice were randomized to receive: ceftazidime, 500 mg/kg SC q4hxtwo doses alone; azithromycin, 20 mg/kg SCxone dose alone; ceftazidime plus azithromycinxone dose; ceftazidime plus azithromycinxtwo doses (1 and 24 h); ceftazidime plus prophylactic azithromycin (three doses at -48, -24, 1 h); or no treatment (control). A significant decrease in the rate of mortality was observed in animals treated with all ceftazidime plus azithromycin groups when compared with those receiving ceftazidime alone. These data indicate a potential role for adjunctive azithromycin therapy in P. aeruginosa infection.