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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
Published on: February 9, 2011
Decline in macrolide-resistant Streptococcus pyogenes isolates from French children
Camille d'Humières1, Robert Cohen, Corinne Levy
1Laboratoire d'Etudes de Génétique Bactérienne dans les infections de l'enfant (EA3105), Université Denis Diderot-Paris 7, Service de Microbiologie, Hôpital Robert Debré, 75019 Paris, France.
International Journal of Medical Microbiology : IJMM
|October 30, 2012
Summary
Macrolide resistance in French group A Streptococcus (GAS) pharyngitis isolates is very low. Erythromycin resistance was found in 3.2% of isolates, with erm(B) being the most common resistance gene.
Area of Science:
- Microbiology
- Infectious Diseases
- Molecular Epidemiology
Background:
- Group A Streptococcus (GAS) is a significant cause of bacterial pharyngitis in children.
- Macrolide antibiotics are commonly used for GAS infections, making antibiotic resistance a critical public health concern.
- Monitoring macrolide resistance patterns is essential for guiding effective treatment strategies.
Purpose of the Study:
- To determine the prevalence of macrolide resistance in GAS isolates from children with pharyngitis in France.
- To identify the specific resistance genes and serotypes associated with macrolide-resistant GAS.
- To assess the impact of declining macrolide consumption on resistance rates.
Main Methods:
- Collection of 585 GAS isolates from French children diagnosed with pharyngitis.
- Antimicrobial susceptibility testing, focusing on erythromycin resistance.
- Molecular characterization of resistance genes (mef(A), erm(A), erm(B)).
- Serotyping (emm types) and multilocus sequence typing (MLST) of resistant isolates.
Main Results:
- Nineteen out of 585 (3.2%) GAS isolates exhibited erythromycin resistance.
- The predominant resistance genes were erm(B) (52.6%), mef(A) (31.6%), and erm(A) (15.8%).
- Resistant isolates represented 7 distinct emm types and 7 corresponding MLST types, indicating diverse genetic backgrounds.
Conclusions:
- The overall rate of macrolide resistance in GAS causing pharyngitis in French children is currently very low.
- The observed low resistance rate may be linked to a decrease in macrolide antibiotic consumption.
- Continued surveillance of GAS antibiotic resistance is crucial for maintaining treatment efficacy.
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Introduction
Acute pharyngitis is the inflammation of the back of the throat (pharynx), commonly resulting in a sore throat. It is a frequently encountered condition that prompts individuals to seek medical advice.
Classification
Acute pharyngitis can be categorized based on its underlying cause:
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Classification
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