PSEUDOMONAS-AERUGINOSA OUTBREAK IN A BURN UNIT - ROLE OF ANTIMICROBIALS IN THE EMERGENCE OF MULTIPLY RESISTANT STRAINS

An environmental survey and a cohort study were done to analyze an out break of infections in a burn unit caused by a serotype O:11 and a mul tidrug-resistant serotype O:12 Pseudomonas aeruginosa. The P. aerugino sa O:11 outbreak was controlled by eradicating an environmental source , contaminated hydrotherapy equipment. To assess risk factors for infe ctions caused by P. aeruginosa O:12, 15 infected burn patients were co mpared with 32 noninfected burn patients hospitalized during the outbr eak. Patients had similar extent, severity, location, and care of burn injuries, exposure to invasive procedures, and past history of P. aer uginosa infection. Prior treatment with ceftazidime (3 g/day) was the only independent risk factor for P. aeruginosa O:12 infection. The out break was controlled by increasing the daily administration of ceftazi dime from 3 to 6 g and by a reinforcement of isolation precautions.