cefditoren-pivoxil and Respiratory-Tract-Infections

A nationwide multicenter susceptibility surveillance study (Susceptibility to the Antimicrobials Used in the Community in España [SAUCE] project), SAUCE-4, including 2,559 Streptococcus pneumoniae, 2,287 Streptococcus pyogenes, and 2,736 Haemophilus influenzae isolates was carried out from May 2006 to June 2007 in 34 Spanish hospitals. Then, the results from SAUCE-4 were compared to those from all three previous SAUCE studies carried out in 1996-1997, 1998-1999, and 2001-2002 to assess the temporal trends in resistance and the phenotypes of resistance over the 11-year period. In SAUCE-4, on the basis of the CLSI breakpoints, penicillin (parenteral, nonmeningitis breakpoint) and cefotaxime were the antimicrobials that were the most active against S. pneumoniae (99.8% and 99.6%, respectively). Only 0.9% of isolates had a penicillin MIC of > or = 2 microg/ml. In S. pyogenes, nonsusceptibility to erythromycin was observed in 19.4% of isolates. Among the H. influenzae isolates, a beta-lactamase-positive prevalence of 15.7% was found. A statistically significant temporal decreasing trend over the 11-year period was observed for nonsusceptibility (from 60.0% to 22.9%) and resistance (from 36.5% to 0.9%) to penicillin and for the proportion of erythromycin-resistant isolates of S. pneumoniae of the macrolide-lincosamide-streptogramin B (MLS(B)) phenotype (from 98.4% to 81.3%). A similar trend was observed for the prevalence of ampicillin resistance (from 37.6% to 16.1%), beta-lactamase production (from 25.7% to 15.7%), and beta-lactamase-negative ampicillin resistance (BLNAR) in H. influenzae (from 13.5% to 0.7%). Among erythromycin-resistant isolates of S. pyogenes, a significant increasing trend in the prevalence of MLS(B) was observed (from 7.0% to 35.5%). SAUCE-4 confirms a generalized decline in the resistance of the main respiratory pathogens to the antimicrobials as well as a shift in their resistance phenotypes.

Topics: Ampicillin; Anti-Bacterial Agents; Cefotaxime; Erythromycin; Haemophilus influenzae; Lincosamides; Macrolides; Microbial Sensitivity Tests; Penicillins; Respiratory Tract Infections; Spain; Streptococcus pneumoniae; Streptococcus pyogenes; Streptogramin B

We evaluated the recent prevalence of antimicrobial-resistant Haemophilus influenzae isolated from the upper respiratory tracts (URT) of patients in Japan. Mutations in the ftsI gene, which encodes penicillin binding protein 3 (PBP3), and the clonal dissemination of the resistant strains were also investigated. A total of 264 H. influenzae isolates were collected from patients with URT infections. According to the criteria of the Clinical and Laboratory Standards Institute for the susceptibility of H. influenzae to ampicillin (AMP), the isolates were distributed as follows: 161 (61.0%) susceptible strains (MIC < or = 1 microg/ml), 37 (14.0%) intermediately resistant strains (MIC = 2 microg/ml), and 66 (25.0%) resistant strains (MIC > or = 4 microg/ml). According to PCR-based genotyping, 172 (65.1%) of the isolates had mutations in the ftsI gene and were negative for the beta-lactamase (bla) gene. These 172 isolates were thus defined as genetically beta-lactamase-negative ampicillin-resistant (gBLNAR) strains. The ftsI mutant group included 98 (37.1%) strains with group I/II mutations in the variable mutated region (group I/II gBLNAR) and 74 (28.0%) strains with group III mutations in the highly mutated region (group III gBLNAR). Eighty-seven (33.0%) of the isolates were genetically beta-lactamase-negative ampicillin-susceptible (gBLNAS) strains. The group III gBLNAR strains showed resistance to beta-lactams. Only five strains (1.9%) were positive for a bla gene encoding TEM-type beta-lactamase. The three clusters consisting of 16 strains found among the 61 BLNAR strains (MIC > or = 4 microg/ml and without the bla gene) showed identical or closely related DNA restriction fragment patterns. Those isolates were frequently identified among strains with a MIC to AMP of 16 microg/ml. The current study demonstrates the apparent dissemination and spread of a resistant clone of H. influenzae among medical centers in Japan. The gBLNAR strains show a remarkable prevalence among H. influenzae isolates, with the prevalence increasing with time. This fact should be taken into account when treating URT infections.

Topics: Adolescent; Adult; Ampicillin; Ampicillin Resistance; Anti-Bacterial Agents; beta-Lactamases; Child; Child, Preschool; Female; Gene Frequency; Genotype; Haemophilus influenzae; Humans; Infant; Infant, Newborn; Japan; Male; Microbial Sensitivity Tests; Middle Aged; Mutation; Polymerase Chain Reaction; Respiratory Tract Infections