Correlation between group B streptococcus GBS capsular typing, tetracycline and macrolide resistance genes in colonizing maternal-newborn

Introduction and Objectives: Group B streptococcus (GBS) is one of important causative agents of infection in newborns. The distribution of GBS trains with reduced penicillin susceptibility and increasing resistance to macrolides are considered as global concern. The aim objective of the current study was to determine the relationship between GBS isolates of colonizing maternal-newborn and frequency of tetracyclin and erythromycin resistance genes in pregnant women. Materials and Methods: Samples were collected from recto-vaginal of pregnant women and the ears and noses of their newborns from 2012 to 2014, Semnan province. Capsular types and resistance genes to erythromycin and tetracycline were detect in GBS using PCR and multiplex PCR method. Results: GBS prevalence was in rectum 9.5%, vagina 27.9%, in the ear & nose infants respectively 28.6% & 26.1%. The highest and lowest antibiotic resistance were observed in tetracycline, erythromycin and gentamicin. The frequency of capsular typing including type III 20 (33.3%), II12 (20%), Ib10 (16.7%), v 9 (15%), IV (8.3%). 6.7% of samples were nontypable. The capsular genes VIII, VII, Ia andVI not detected. There was a significant correlation between tetM, ermB, and ermA gene with type of capsular, but it wasn’t relationship between tetK, ermTR andermC with capsular types. Conclusions: The multi resistance to penicillin, macrolides and tetracycline in type IIa III with correlation between type II, III and tetM, ermB, ermA genes could be as serious problem for treatment of GBS infections.

کلیدواژه ها:

GBS ، Antibiotic resistance ، Capsular typing