Detection of macrolide resistance genes in culture-negative specimens from Bangladeshi children with invasive pneumococcal diseases.
J Glob Antimicrob Resist
; 8: 131-134, 2017 03.
Article
em En
| MEDLINE
| ID: mdl-28132873
ABSTRACT
OBJECTIVES:
In recent years, an increasing prevalence of macrolide resistance among pneumococci in Bangladesh has been observed. However, the scenario remains incomplete, as few isolates (<1%) are available from pneumonia cases and most pneumococcal meningitis cases (>80%) are culture-negative. This study optimised a triplex PCR method to detect macrolide resistance genes (MRGs) (mefA and ermB) and cpsA from culture-negative pneumococcal cases to predict the prevalence and level of macrolide resistance.METHODS:
The presence of MRGs among pneumococcal strains (n=153) with a wide range of erythromycin MICs (<0.5 to ≥256mg/L) was determined by PCR. Triplex PCR was validated by simultaneous detection of MRG(s) and cpsA in culture-negative clinical specimens and corresponding isolates. The known impact of the presence of specific MRG(s) on MICs of strains was used to predict the MICs of non-culturable strains based on the presence/absence of MRG(s) in the specimens.RESULTS:
None of the erythromycin-susceptible isolates possessed any of the MRGs, and all non-susceptible strains had ≥1 MRG. MICs were 2-16mg/L and ≥256mg/L for 93% of strains with mefA and ermB, respectively, whereas 100% of isolates with both genes had MICs≥256mg/L. PCR for body fluids showed 100% concordance with corresponding isolates when tested for MRG(s) in parallel.CONCLUSIONS:
Erythromycin MICs can be predicted for non-culturable strains with 93-100% precision based on detection of ermB and/or mefA. This method will be useful for establishing comprehensive surveillance for macrolide resistance among pneumococci, specifically in the population with prior antibiotic use.Palavras-chave
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Base de dados:
MEDLINE
Assunto principal:
Infecções Pneumocócicas
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Streptococcus pneumoniae
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Testes de Sensibilidade Microbiana
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Meningites Bacterianas
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Bacteriemia
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Farmacorresistência Bacteriana
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Reação em Cadeia da Polimerase Multiplex
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article