Influence of penicillin/amoxicillin non-susceptibility on the activity of third-generation cephalosporins against Streptococcus pneumoniae.

Eur J Clin Microbiol Infect Dis

Spanish National Reference Pneumococcal Laboratory, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo Km. 2, 28220, Majadahonda, Madrid, Spain.

Published: January 2008

To study the influence of penicillin/amoxicillin non-susceptibility on the activity of third-generation cephalosporins, 430 consecutive penicillin non-susceptible Streptococcus pneumoniae 2007 isolates received in the Spanish Reference Pneumococcal Laboratory were tested. For comparative purposes, 625 penicillin-susceptible 2007 isolates were also tested. Susceptibility was determined by agar dilution using Mueller-Hinton agar supplemented with 5% sheep blood. Penicillin-susceptible strains were susceptible to amoxicillin, cefotaxime and ceftriaxone, 99.8% to cefpodoxime and 99.5% to cefdinir, and were inhibited by 0.12 microg/ml of cefditoren and 4 microg/ml of cefixime. Penicillin-intermediate strains were susceptible to cefotaxime and ceftriaxone, with <50% susceptibility to cefdinir and cefpodoxime. The MIC(50) and MIC(90) values of cefditoren were 0.25 microg/ml and 0.5 microg/ml, respectively, whereas cefixime exhibited only marginal activity (MIC(90)=16 microg/ml). Penicillin-resistant strains were resistant to cefdinir and cefpodoxime, with 74.8% and 94.1% susceptibility to cefotaxime and ceftriaxone, respectively. Cefditoren MIC(50)/MIC(90) (0.5/1 microg/ml) were lower than cefotaxime and ceftriaxone. Among amoxicillin non-susceptible strains, susceptibility to cefdinir and cefpodoxime was <10%, and susceptibility to cefotaxime decreased from 87.9% in the intermediate category to 63.0% in the resistant group. Cefditoren MIC(50)/MIC(90) (0.5/1 microg/ml) were lower than cefotaxime. In conclusion, the activity of cefixime, cefdinir and cefpodoxime was highly affected by penicillin/amoxicillin non-susceptibility, while parenteral third-generation cephalosporins exhibited higher intrinsic activity (MIC(90)=1 microg/ml for penicillin-resistant and 2 microg/ml for amoxicillin-resistant strains). Cefditoren exhibited one-dilution lower MIC(90) values for these strains, even against those of the most troublesome serotypes.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10096-007-0402-5DOI Listing

Publication Analysis

Top Keywords

influence penicillin/amoxicillin
8
penicillin/amoxicillin non-susceptibility
8
non-susceptibility activity
8
activity third-generation
8
third-generation cephalosporins
8
streptococcus pneumoniae
8
2007 isolates
8
strains susceptible
8
cefotaxime ceftriaxone
8
cephalosporins streptococcus
4

Similar Publications

Article Synopsis
  • Bacillus anthracis, the bacteria causing anthrax, poses risks to both human and animal health, particularly in agricultural areas around the world.
  • The study identifies a specific lineage of B. anthracis from 1960s Brazil, confirming its classification and antimicrobial susceptibility through advanced sequencing technologies and various tests.
  • Findings indicate that while the isolate IAL52 is susceptible to several antibiotics, it is resistant to ciprofloxacin, highlighting the importance of understanding different bacterial strains for effective treatment and tracking of this zoonotic disease.
View Article and Find Full Text PDF

Antibiotics' (ATBs) occurrence in soil ecosystems has a relevant effect in the structure and functionality of edaphic microbial communities, mainly because of their amendment with manure and biosolids that alter their key ecological functions. In this study, the impact of eight widely consumed ATBs on a natural soil microbial community, characterized through 16 S rRNA gene sequencing, was evaluated. Changes induced by the ATBs in the growth of the soil microbiota and in the community-level physiological profiling (CLPP), using Biolog EcoPlates™, were measured as endpoint.

View Article and Find Full Text PDF

Antibiotic prophylaxis for preventing bacterial endocarditis following dental procedures.

Cochrane Database Syst Rev

May 2022

Cochrane Oral Health, Division of Dentistry, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.

Background: Infective endocarditis is a severe infection arising in the lining of the chambers of the heart. It can be caused by fungi, but most often is caused by bacteria. Many dental procedures cause bacteraemia, which could lead to bacterial endocarditis in a small proportion of people.

View Article and Find Full Text PDF

Contamination of waters with pharmaceuticals is an alarming problem as it may support the evolution of antimicrobial resistance. Therefore, fast and cost-effective analytical methods for potential on-site analysis are desired in order to control the water quality and assure the safety of its use as a source of drinking water. Antibody-based methods, such as the enzyme-linked immunosorbent assay (ELISA), can be helpful in this regard but can also have certain pitfalls in store, depending on the analyte.

View Article and Find Full Text PDF

Antibiotics continue to be the standard-of-care for bacterial vaginosis (BV), although recurrence rates are high. Vaginal probiotics may improve durability of BV treatment, although few probiotics for vaginal health contain Lactobacillus spp. that commonly colonize the lower female genital tract.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!