Imipenem therapy of Pseudomonas aeruginosa and other serious bacterial infections

Imipenem is the first of a new class of beta-lactam antimicrobial agents with remarkable and extremely potent in vitro activity against most commonly isolated bacterial pathogens, including Staphylococcus aureus, enterococcus, members of the family Enterobacteriaceae, Pseudomonas aeruginosa, Bacteroides fragilis, and Hemophilus influenzae. The clinical efficacy and toxicity of imipenem were evaluated in 35 patients with 38 different infections. The overall clinical response was favorable (infections cured or improved) in 89% of the infections (34 of 38). Of the 17 infections with P. aeruginosa, 15 were cured or improved. However, P. aeruginosa isolates resistant to imipenem emerged during the therapy of six infections, and two cases of P. aeruginosa septicemia later relapsed after imipenem therapy. Gastrointestinal toxicity (nausea with or without emesis) occurred in 17% of the patients (6 of 35) but was ameliorated by slowing the rate of intravenous infusion or lowering the dose of imipenem. Except for certain severe P. aeruginosa infections, imipenem is effective and relatively safe therapy for infections caused by susceptible organisms.