Antimicrobial Use Guidelines (AMUG) version 21 - UW Health

Pseudomonas aeruginosa and other gram-negative pathogens including Enterobacter spp., Serratia spp. andCitrobacter spp. (PESC organisms)Issue: Antimicrobial orders targeted against Pseudomonas aeruginosa account for 10% of all hospital orders, and 25% ofall empiric and confirmed bloodstream infections. Double coverage of these and other gram-negative organisms is oftencontinued indiscriminately.Suggestion: See discussion of pulmonary infections. The use of first-, second- and third-generation cephalosporinsfor extended periods of time with these PESC organisms in circumstances with high bacterial inoculum mayresult in the development of resistance to the cephalosporins. Caution is advised for high inoculum and longduration of therapy. Cefepime is usually active and stable for these organisms under these circumstances.