HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS REGISTER		Author Keyword(s) Vol Page [Advanced]

This Article Full Text Full Text (PDF) All Versions of this Article: jcp.2006.043489v1 60/10/1140    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this link to a friend Similar articles in this journal Similar articles in PubMed Add article to my folders Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Busetti, M. Articles by Campello, C. Search for Related Content PubMed PubMed Citation Articles by Busetti, M. Articles by Campello, C. Pubmed/NCBI databases Medline Plus Health Information High Risk Pregnancy Infections and Pregnancy Streptococcal Infections

Group B streptococcus prevalence in pregnant women from North-Eastern Italy: advantages of a screening strategy based on direct plating plus broth enrichment

Department of Public Medicine Sciences, UCO Hygiene and Preventive Medicine, University of Trieste, and IRCCS "Burlo Garofolo", Trieste, Italy

Correspondence to:
Professor C Campello, Department of Public Medicine Sciences, UCO Hygiene and Preventive Medicine, Via dell’Istria 65/1, 34137 Trieste, Italy; campello{at}burlo.trieste.it

Aims: To assess the sensitivity of a combined selective broth enrichment technique plus selective plating for the detection of group B streptococcus (GBS) colonisation in a large cohort of pregnant women from North-Eastern Italy.

Methods: During 2002–2005, 5020 pregnant women were screened between the 35th and the 37th week of gestation. A lower vaginal sample and a rectal sample were collected and inoculated onto LIM broth and a selective colistin aztreonam blood agar plate (CAP). Direct agar plates were examined after 18–24 hours and, if negative, after 48 hours. LIM broth was subcultured after 18–24 hours onto a Columbia blood agar plate. All colonies suggestive for GBS were submitted to phenotypic identification.

Results: 901 Women (17.9%) were positive for GBS. On 728 positive samples, corresponding to patients enrolled between 2003 and 2005, the results of selective direct plating and selective broth enrichment were compared. A total of 561 (77.1% of positive samples, corresponding to 13.9% of patients) were positive on direct selective agar; an additional 167 isolates (22.9% of samples, 4.1% of patients) were recovered from the LIM broth subculture.

Conclusions: The prevalence of GBS carriage in this population-based study is a reliable estimate considering the sensitivity of the microbiological methods used, the rate of attendance of pregnant women to clinical and laboratory settings and the compliance to the protocol. Results confirm that the combination of selective enrichment broth and selective direct plating is a time-saving and sensitive method.

Abbreviations: CAP, colistin aztreonam blood agar plate; GBS, group B streptococcus

Keywords: GBS; pregnant women; prevalence; culture methods