Background: Ertapenem is a novel carbapenem with activity against both penicillin-susceptible (MIC < or = 0.06 mg/L) and penicillin-non-susceptible (MIC > or = 0.12 mg/L) Streptococcus pneumoniae. This study assessed the pharmacodynamic activity of ertapenem against penicillin-susceptible and penicillin-non-susceptible S. pneumoniae using an in vitro pharmacodynamic model.
Methods: Fifteen S. pneumoniae strains including 3 penicillin-susceptible and 12 penicillin-non-susceptible [4 penicillin-intermediate (MIC 0.12-1 mg/L) and 8 penicillin-resistant (MIC > or = 2 mg/L); with different resistance phenotypes including erythromycin-resistant (MIC > or = 1 mg/L), ciprofloxacin-resistant (MIC > or = 4 mg/L) and doxycycline-resistant (MIC > or = 8 mg/L)] were studied. The in vitro pharmacodynamic model was inoculated with 1 x 10(6) cfu/mL and ertapenem was dosed once daily at 0 and 24 h to simulate f (free) Cmax and t(1/2) obtained after a standard 1 g intravenous once daily dose in healthy volunteers (fCmax 15 mg/L, t(1/2) 4 h). Sampling was performed for 48 h to assess viable growth.
Results: Ertapenem T(> MIC) > or = 80% (ertapenem MICs < or = 0.5 mg/L) resulted in bactericidal (> or = 3 log10 killing) activity at 12, 24 and 48 h with complete eradication of penicillin-susceptible and penicillin-non-susceptible S. pneumoniae from the model with no regrowth over the 48 h study period. Ertapenem T(> MIC) < or = 63% (ertapenem MIC > or = 1 mg/L) resulted in bactericidal activity at 12 h with regrowth at 24 and 48 h. The observed MICs for S. pneumoniae of ertapenem studied in the in vitro model did not change during the 48 h period, even for strains where regrowth occurred.
Conclusions: Ertapenem is bactericidal against both penicillin-susceptible and penicillin-non-susceptible S. pneumoniae (ertapenem MICs < or = 0.5 mg/L) when simulating free drug after 1 g intravenous once daily dosing.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1093/jac/dkl433 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Systematic review of the clinical outcomes of pneumonia with a penicillin-group resistant pneumococcus in respiratory and blood culture specimens in children in low- and middle-income countries.
J Glob Health
August 2022
Department of Paediatrics, University of Melbourne, Melbourne, Australia.
Background: Streptococcus pneumoniae is one of the most common bacteria causing pneumonia and the World Health Organization (WHO) recommends first-line treatment of pneumonia with penicillins. Due to increases in the frequency of penicillin resistance, this systematic review aimed to determine the clinical outcomes of children with pneumonia in low- and middle-income countries (LMICs), with penicillin-group resistant pneumococci in respiratory and/or blood cultures specimens.
Methods: English-language articles from January 2000 to November 2020 were identified by searching four databases.
Aim: The purpose of the surveillance performed from October to December in 2010-2017 was to monitor the trends in the susceptibility to beta-lactam and macrolide antibiotics in Streptococcus pneumoniae isolates from respiratory tract infections in the Czech Republic.
Material And Methods: Between 42 and 55 laboratories participated in the study every year. Consecutive non-duplicate pneumococcal isolates from relevant microbiological specimens from patients with community-acquired bacterial respiratory tract infection were sequentially included in the study.
Pneumococcal susceptibility to antibiotics in carriage: a 17 year time series analysis of the adaptive evolution of non-vaccine emerging serotypes to a new selective pressure environment.
J Antimicrob Chemother
October 2019
National Reference Center for Pneumococci, Centre Hospitalier Intercommunal de Créteil, Créteil, France.
Background: Pneumococcal conjugate vaccine (PCV) implementations led to major changes in serotype distribution and antibiotic resistance in carriage, accompanied by changes in antibiotic consumption.
Objectives: To assess the dynamic patterns of antimicrobial non-susceptibility across non-PCV13 serotypes following PCV implementations.
Methods: We conducted a quasi-experimental interrupted time series analysis based on a 17 year French nationwide prospective cohort.
Evolution of Penicillin Non-susceptibility Among Isolates Recovered From Asymptomatic Carriage and Invasive Disease Over 25 years in Brazil, 1990-2014.
Front Microbiol
March 2019
Instituto de Microbiologia Paulo de Goes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
is a major cause of community-acquired pneumonia and meningitis, and it is also found as a commensal, colonizing the human upper respiratory tract of a portion of the human population. Its polysaccharide capsule allows the recognition of more than 90 capsular types and represents the target of the currently available pneumococcal conjugate vaccines (PCVs), such as the 10-valent (PCV10) and the 13-valent (PCV13). Penicillin non-susceptible pneumococci (PNSP) have been listed as one of the current major antimicrobial-resistant pathogen threats.
View Article and Find Full Text PDFAntimicrobial susceptibility of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis isolated from community-acquired respiratory tract infections in China: Results from the CARTIPS Antimicrobial Surveillance Program.
J Glob Antimicrob Resist
June 2016
Department of Infectious Diseases, Guangzhou Institute of Respiratory Disease, Guangzhou, China.
This study investigated the antimicrobial susceptibilities of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis isolates causing adult community-acquired respiratory tract infections (CARTIs) in China. A multicentre resistance surveillance study (CARTIPS) investigating 1046 clinical isolates from 19 hospitals in China was conducted from 2013 to 2014. Based on the minimum inhibitory concentration (MIC) breakpoints of oral penicillin, the percentages of penicillin-resistant, penicillin-intermediate and penicillin-susceptible S.
View Article and Find Full Text PDFWant 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!