Antimicrobial susceptibility of Streptococcus pneumoniae isolates from vaccinated and non-vaccinated patients with a clinically confirmed diagnosis of community-acquired pneumonia in Belgium.

Abstract

We assessed the in vitro susceptibility of Streptococcus pneumoniae isolates from patients with confirmed community-acquired pneumonia (CAP) to β-lactams, macrolides and fluoroquinolones and the association of non-susceptibility and resistance with serotypes/serogroups (STs/SGs), patient's risk factors and vaccination status. Samples (blood or lower respiratory tract) were obtained in 2007-2009 from 249 patients (from seven hospitals in Belgium) with a clinical and radiological diagnosis of CAP [median age 61 years (11.6% aged <5 years); 85% without previous antibiotic therapy; 86% adults with level II Niederman's severity score]. MIC determination (EUCAST breakpoints) showed for: (i) amoxicillin, 6% non-susceptible; cefuroxime (oral), 6.8% resistant; (ii) macrolides: 24.9% erythromycin-resistant [93.5% erm(B)-positive] but 98.4% telithromycin-susceptible; and (iii) levofloxacin and moxifloxacin, all susceptible. Amongst SGs: ST14, all resistant to macrolides and most intermediate to β-lactams; SG19 (>94% ST19A), 73.5% resistant to macrolides and 18-21% intermediate to β-lactams; and SG6, 33% resistant to clarithromycin. Apparent vaccine failures: 3/17 for 7-valent vaccine (children; ST6B, 23F); 16/29 for 23-valent vaccine (adults ST3, 7F, 12F, 14, 19A, 22F, 23F, 33F). Isolates from nursing home residents, hospitalised patients and patients with non-respiratory co-morbidities showed increased MICs for amoxicillin, all β-lactams, and β-lactams and macrolides, respectively. Regarding antibiotic susceptibilities: (i) amoxicillin is still useful for empirical therapy but with a high daily dose; (ii) cefuroxime axetil and macrolides (but not telithromycin) are inappropriate for empirical therapy; and (iii) moxifloxacin and levofloxacin are the next 'best empirical choice' (no resistant isolates) but levofloxacin will require 500 mg twice-daily dosing for effective coverage.

• Authors: Ann Lismond, Sylviane Carbonnelle, Jan Verhaegen, Patricia Schatt, Annelies De Bel, Paul Jordens, Frédérique Jacobs, Anne Dediste, Frank Verschuren, Te-Din Huang, Paul M Tulkens, Youri Glupczynski, Françoise Van Bambeke
• Journal: International journal of antimicrobial agents (Int J Antimicrob Agents) Vol. 39 Issue 3 Pg. 208-16 (Mar 2012) ISSN: 1872-7913 [Electronic] Netherlands
• PMID: 22245497 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Chemical References

• Anti-Bacterial Agents
• Aza Compounds
• Fluoroquinolones
• Quinolines
• beta-Lactams
• Amoxicillin
• Clarithromycin
• Moxifloxacin

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Amoxicillin (pharmacology)
• Anti-Bacterial Agents (pharmacology)
• Aza Compounds (pharmacology)
• Belgium (epidemiology)
• Child
• Child, Preschool
• Clarithromycin (pharmacology)
• Community-Acquired Infections (diagnosis, drug therapy, microbiology)
• Comorbidity
• Drug Resistance, Multiple, Bacterial
• Fluoroquinolones
• Humans
• Microbial Sensitivity Tests (standards)
• Middle Aged
• Moxifloxacin
• Pneumonia, Pneumococcal (diagnosis, drug therapy, microbiology)
• Quinolines (pharmacology)
• Streptococcus pneumoniae (drug effects, isolation & purification, pathogenicity)
• Vaccination
• Young Adult
• beta-Lactams (pharmacology)