Phenotypes and Genotypes of Macrolide-Resistant Streptococcus Pneumoniae

Abstract

_Macrolide resistance in Streptococcus pneumoniae (S. pneumoniae) is a worldwide problem. Aims_ The aim of this work was to analyze the phenotypes, genotypes, and clonal relatedness among macrolide-resistant S. pneumoniae strains isolated from various clinical specimens in our hospital. Study Design_ Cross-sectional study. Methods_ 80 non-duplicate S. pneumoniae strains were analyzed by polymerase chain reaction for both the erm (B) and mef (A) genes. Results_ Macrolide resistance was observed in 22.5% (18 strains) of strains. Two (11.2%) isolates possessed mef (A), eight possessed erm (B) (44.4%) and eight strains (44.4%) were positive for both erm (B) and mef (A) genes. Although BOX-PCR of 18 macrolide-resistant strains revealed 11 band patterns, they clustered as seven clones with a genetic distance _10% to each other. Eight isolates possessed both erm (B) and mef (A) genes and belonged to a single clone (44.44% of all macrolide-resistant strains). Conclusion_ Increased positivity rates for both resistance genes have also been reported from other hospitals in Turkey, but this is the first study from Turkey showing the clonal dissemination of both resistance genes_

Keywords

• erm (B), BOX-PCR, Macrolide resistance, mef (A), Streptococcus pneumoniae

Kaynakça

1. 1. Daneman N, McGeer A, Green K, Low DE; Toronto Invasive Bacterial Diseases Network. Macrolide resistance in bacteremic pneumococcal disease: implications for patient management. Clin Infect Dis 2006;43:432-8. [CrossRef]
2. 2. Calatayud L, Ardanuy C, Tubau F, Rolo D, Grau I, Pallarés R, et al. Serotype and genotype replacement among macrolide-resistant invasive pneumococci in adults: mechanisms of resistance and association with different transposons. J Clin Microbiol 2010;48:1310-6. [CrossRef]
3. 3. Clinical and Laboratory Standards Institute. Performance standards for antimicrobial susceptibility testing M100-S23. 2013; Wayne, Pa: USA.
4. 4. Montanari MP, Mingoia M, Giovanetti E, Varaldo PE. Differentiation of resistance phenotypes among erythromycin-resistant pneumococci. J Clin Microbiol 2001;39:1311-5. [CrossRef]
5. 5. Sutcliffe J, Grebe T, Tait-Kamradt A, Wondrack L. Detection of erythromycin-resistant determinants by PCR. Antimicrob. Agents Chemother 1996;40:2562-6.
6. 6. Van Belkum A, Sluijter M, de Groot R, Verbrugh H, Hermans PW. Novel BOX repeat PCR assay for high-resolution typing of Streptococcus pneumoniae strains. J Clin Microbiol 1996;34:1176-9.