RESUMEN
In order to evaluate the efficacy of cephalosporins against Gram-negative bacteria in the intensive care unit [ICU], we tested the susceptibilities of 88 consecutive Gram-negative bacilli to cefuroxime, cefotaxime, ceftazidime and cefepime. Ceftazidime-resistant strains were further tested against ceftazidime/clavulanic acid [ceftazclav] for production of extended spectrum Beta-lactamases [ESBLs]. The most common isolate was Pseudomonas aeruginosa [20] followed by Klebsiella pneumoniae [19] and Escherichia coli. Sputum and urine specimens gave the highest yield of bacterial isolates. Most strains were susceptible to cefepime [89%], and least to cefuroxime [35%]. 72% of the strains were susceptible ceftazidime, 56% to ceftriaxone and 53% to cefotaxime. The activity of ceftazidime against Pseudomonas spp. was similar to that of cefepime. Three stains of Klebsiella spp., two Enterobacter spp. and one E. coli were resistant to ceftazidime, but sensitive to ceftazclav and were therefore identified as ESBL producers. Resistance to cephalosporins was mostly encountered with Enterobacter spp. and Acinetobacter spp. All cefepime-resistant strains were highly resistant to ceftazidime, but some ceftazidime-resistant strains were susceptible to cefepime. Cefepime, the most in-vitro effective cephalosporin against our strains may have a place in clinical use