Phenotypic and genetic differences among group B Streptococcus recovered from neonates and pregnant women in Shenzhen, China: 8-year study

Benqing Wu; Jinzhen Su; Li Li; Weiyuan Wu; Jingsong Wu; Yuemei Lu; Wenqing Li; Jin’e Cheng; Xunhong Liang

doi:10.1186/s12866-019-1551-2

BMC Microbiology (Aug 2019)

Phenotypic and genetic differences among group B Streptococcus recovered from neonates and pregnant women in Shenzhen, China: 8-year study

Benqing Wu,
Jinzhen Su,
Li Li,
Weiyuan Wu,
Jingsong Wu,
Yuemei Lu,
Wenqing Li,
Jin’e Cheng,
Xunhong Liang

Affiliations

Benqing Wu: Department of Neonatal Intensive Care Unit, University of Chinese Academy of Science-Shenzhen Hospital
Jinzhen Su: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen
Li Li: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen
Weiyuan Wu: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen
Jingsong Wu: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen
Yuemei Lu: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen
Wenqing Li: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen
Jin’e Cheng: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen
Xunhong Liang: Department of Laboratory Medicine, Shenzhen People’s Hospital, Second Clinical Medical College of Jinan University, Key Laboratory of Pathogenic Microorganism and Bacterial Resistance Surveillance in Shenzhen

DOI: https://doi.org/10.1186/s12866-019-1551-2
Journal volume & issue: Vol. 19, no. 1
pp. 1 – 9

Abstract

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Abstract Background Group B Streptococcus (GBS) is a leading cause of early-onset disease (EOD) and late-onset disease (LOD) in infants. We sought to investigate the antibiotic susceptibility profiles, resistance genes, virulence-related genes, serotype distribution and genotypic characteristics of GBS recovered from infected or colonized neonates and pregnant women in a tertiary teaching hospital in Shenzhen, China, from 2008 to 2015. Results High resistance rates of erythromycin (66.7–100%) were detected among early-onset GBS (EOGBS), late-onset GBS (LOGBS), neonatal colonizing GBS (NCGBS) and maternal colonizing GBS (MCGBS). 89.5–100% of four groups of GBS isolates showed resistance to tetracycline. More than 90 % of erythromycin resistant isolates of EOGBS (8/8, 100%), LOGBS (16/17, 94.1%) and NCGBS (10/11, 90.9%) harbored ermB, while only 9.1–17.6% harbored mefA/E. By contrast, 55.8% (24/43) and 62.8% (27/43) of erythromycin resistant MCGBS isolates carried ermB and mefA/E genes, respectively. The tetO gene was more common in tetracycline resistant EOGBS (10/11, 90.9%), LOGBS (17/17, 100%) and NCGBS (10/11, 90.9%), compared to tetracycline resistant MCGBS (12/51, 23.5%). Additionally, the tetM gene accounted for 90.9% (10/11), 76.5% (13/17), 45.5% (5/11) and 80.4% (41/51) of four groups of isolates, respectively. Serotype III was the most predominant in EOGBS (8/12, 66.7%) and LOGBS (15/17, 88.2%), while serotype Ib accounted for 50.0% (6/12) of NCGBS, and serotype Ia and III accounted for 45.6% (26/57) and 33.3% (19/57) of MCGBS, respectively. Sequence type 17 (ST17) was the most common in EOGBS (6/12, 50%) and LOGBS (12/17, 70.6%), while ST12 was predominant in NCGBS (5/12, 41.7%), and five STs (ST19, ST23, ST12, ST103 and ST485) accounted for 66.7% (38/57) of the MCGBS. All serotype III-ST17 isolates recovered from neonates were associated with invasive infections. Conclusions This study shows the meaningful differences in molecular mechanisms of resistance to erythromycin and tetracycline, and the prevalence of serotypes and STs among GBS recovered from neonates and pregnant women. ST17 is predominant in neonatal invasive GBS, but rare in NCGBS and MCGBS.

Published in BMC Microbiology

ISSN: 1471-2180 (Online)
Publisher: BMC
Country of publisher: United Kingdom
LCC subjects: Science: Microbiology
Website: http://www.biomedcentral.com/bmcmicrobiol/

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