A Comparison of Aztreonam Plus Vancomycin and Imipenem Plus Vancomycin as Initial Therapy for Febrile Neutropenic Cancer Patients

Abstract

This study was designed to compare the efficacy of imipenem with that of aztreonam as initial empiric therapy for febrile episodes in neutropenic patients. Both agents were combined with vancomycin during the initial part of empiric therapy. The imipenem regimen cured 76% of the 148 evaluable episodes vs. a 67% cure rate for the 152 episodes treated with the aztreonam regimen. Most of the polymicrobial infections– 10 (77%) of 13 patients treated with imipenem–responded, whereas only five (38%) of 13 patients responded to aztreonam. Although the cost of the imipenem regimen was less than the cost of the aztreonam regimen, it was associated significantly more often with skin rashes (12 of 194 vs. 3 of 189; P <02). In a multivariate analysis, a poor outcome was independently associated with the persistence of neutropenia and the presence of pneumonia. The authors conclude that in a multifactorial analysis that included efficacy, toxicity, and cost, the imipenem and aztreonam regimens were comparable.