Evaluation of Culture, Antigen Detection and Polymerase Chain Reaction for Detection of Vaginal Colonization of Group B Streptococcus (GBS) in Pregnant Women.
OBJECTIVE
Group B Streptococcal infection is an important cause of neonatal morbidity and mortality. Early detection of perinatal vagino-rectal (VR) carriage of Group B Streptococcus (GBS) is important in the management of newborn infections. The objective of the study was to evaluate Culture, antigen detection and Polymerase chain reaction for detection of GBS in Pregnant women.


METHODS
Observational descriptive study was done in a tertiary care hospital in Southern India.


METHODS
VR swabs were collected from 50 women at 35 to 37 weeks of gestation. Culture in a selective Lim enrichment broth with subsequent culture on 5% sheep blood agar, Conventional PCR assay and antigen detection method were performed. The performance of antigen detection and PCR methods were compared with culture.


METHODS
STATISTICAL ANALYSIS was performed by Chi-Square test.


RESULTS
GBS cultures were positive for 16% of the specimen (8 out of 50). Considering culture as a gold standard, Sensitivity, Specificity, Positive predictive value and Negative predictive value of antigen detection was 100%, 92.86%, 72.73%, 100% and similarly for that of PCR was 100%, 45.23%, 25.80%, 100%, respectively.


CONCLUSIONS
Antigen detection method was the rapid, sensitive and specific test for the detection of GBS colonizers during pregnancy.
Assistant Professor, Department of Microbiology, Government Medical College , Thrissur, India .
Kavitha Paul
KP
Konikkara
Professor and Head, Department of Microbiology, Kasturba Medical College , Mangalore, India .
Shrikala
S
Baliga
Associate Professor, Department of Microbiology, Kasturba Medical College , Mangalore, India .
Suchithra
S
Shenoy
Associate Professor, Department of Microbiology, Aua College of Medicine , Antigua, West Indies .
B
B
Bharati
Antigen detection; Group B Streptococcus; Pregnancy