Streptococcus agalactiae colonization and screening approach in high-risk pregnant women in southern Brazil

  • Jeane Zanini da Rocha Medical Microbiology Research Center, Faculty of Medicine, Universidade Federal do Rio Grande - FURG, Rio Grande/RS, Brazil
  • Jéssica Feltraco Medical Microbiology Research Center, Faculty of Medicine, Universidade Federal do Rio Grande - FURG, Rio Grande/RS, Brazil
  • Vanessa Radin Medical Microbiology Research Center, Faculty of Medicine, Universidade Federal do Rio Grande - FURG, Rio Grande/RS, Brazil
  • Carla Vitola Gonçalves Medical Microbiology Research Center, Faculty of Medicine, Universidade Federal do Rio Grande - FURG, Rio Grande/RS, Brazil
  • Pedro Eduardo Almeida da Silva Medical Microbiology Research Center, Faculty of Medicine, Universidade Federal do Rio Grande - FURG, Rio Grande/RS, Brazil
  • Andrea von Groll Medical Microbiology Research Center, Faculty of Medicine, Universidade Federal do Rio Grande - FURG, Rio Grande/RS, Brazil
Keywords: Streptococcus agalactiae, prevalence, premature labor, high-risk pregnancy, Granada medium, GeneXpert

Abstract

Introduction: Considering that Group B Streptococcus (GBS) persists as an important cause of neonatal morbidity and mortality, the objective of this study was to evaluate the frequency of maternal colonization by GBS, comparing the culture by the Granada broth with the GeneXpert real-time PCR diagnostic methods and the impact of chemoprophylaxis in high-risk pregnant women.

Methodology: A prospective cohort of 110 pregnant women hospitalized for gestational complications was formed and recruited following interview and collection of rectovaginal swabs.

Results: The frequency of maternal colonization was 28.2% and statistically associated with Capurro> 37 weeks (p = 0.030) and neonatal infection (p = 0.008). Chemoprophylaxis was offered to 80% of those colonized. Among the pregnant women treated, a fivefold reduction in the rate of prematurity and rate of neonatal infection was observed. The sensitivity was 76.6% and 86.6% in culture and PCR, respectively, with an optimal index of agreement between the methods (K = 0.877). Grenade culture was considered an easy and low-cost method, while GeneXpert presented higher cost and error rate of 10%. However, 23.3% of the pregnant women were diagnosed exclusively by GeneXpert and the results were obtained in two hours.

Conclusions: This study showed a significant prevalence of maternal colonization for GBS and that both culture and molecular methods had peculiarities that allow different applicability, with the culture being feasible for antenatal screening and in the hospital for high-risk pregnant women with no sign of imminent delivery and GeneXpert being prioritized for situations of preterm birth.

Published
2020-04-30
How to Cite
1.
Zanini da Rocha J, Feltraco J, Radin V, Vitola Gonçalves C, Almeida da Silva PE, von Groll A (2020) Streptococcus agalactiae colonization and screening approach in high-risk pregnant women in southern Brazil. J Infect Dev Ctries 14:332-340. doi: 10.3855/jidc.12025
Section
Original Articles