title: In vitro activity of Iclaprim against respiratory and bacteremic isolates of Streptococcus pneumoniae.
abstract: Iclaprim, a novel dihydrofolate reductase inhibitor, inhibited 90% of the clinical isolates (MIC(90)) of Streptococcus pneumoniae (n = 785) collected by a national surveillance program at a concentration of 1 microg/ml. The MIC(90) for iclaprim was 7 doubling dilutions lower for trimethoprim-sulfamethoxazole-susceptible isolates (n = 670; MIC(90), 0.06 microg/ml) than for trimethoprim-sulfamethoxazole-resistant isolates (n = 115; MIC(90), >or=8 microg/ml). The potential clinical utility of iclaprim to treat patients with pneumococcal infections may depend upon the current prevalence of resistance to trimethoprim-sulfamethoxazole in this pathogen.
authors.affiliation: Department of Medical Microbiology and Infectious Diseases, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada. ggzhanel@pcs.mb.ca
authors.forename: George G
authors.initials: GG
authors.lastname: Zhanel
authors.forename: James A
authors.initials: JA
authors.lastname: Karlowsky
mesh_terms: D016470:Bacteremia / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D006801:Humans; D008826:Microbial Sensitivity Tests; D011743:Pyrimidines / Q000494:pharmacology*; D012137:Respiratory System / Q000382:microbiology*; D013296:Streptococcus pneumoniae / Q000187:drug effects*; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology
chemical_list: D011743:Pyrimidines; C486448:iclaprim; D015662:Trimethoprim, Sulfamethoxazole Drug Combination