A study on molecular characterization of macrolide resistance mechanism among isolates of Streptococcus pneumoniae from the southern Marmara region of Turkey, as well as resistance to macrolides and penicillin in these isolates

To determine the distribution of macrolide resistance genes as well as resistance rates in isolated Streptococcus pneumoniae strains from the southern Marmara region of Turkey. Materials and methods: Antimicrobial resistance rates and MIC values were determined by the E-test method in 300 Streptococcus pneumoniae isolates that were isolated from clinical samples. Resistance genes were determined by the polymerase chain reaction (PCR) method in erythromycin-resistant strains. Results: It was found that 11.4% of Streptococcus pneumoniae isolates were resistant to macrolides. The penicillin MIC value was >=0.12 µg/mL in 23% of the strains and 2 µg/mL in 2% of the strains. The erm(B) genotype was observed in 58.8% of all macrolide-resistant strains, 38.2% were of the mef(A) genotype, and 3% were a combination of both genotypes. Conclusion: Based on the data from this study, it was concluded that the local resistance to antibiotics is not as high as that observed in other countries, and the erm(B) genotype was dominant in macrolide-resistant strains. Therefore, it is suggested that macrolide-group antibiotics still be included in treatment protocols.