Evaluation of a rapid latex test for direct detection of Streptococcus agalactiae in various obstetrical and gynaecological disorders.

Cervical samples collected during speculum examination in 413 women were tested for the presence of Streptococcus agalactiae by Gram staining, a new latex agglutination test and standard cultures. The results of each method are reported in correlation with the clinical circumstances of isolation. Gram stain and the latex agglutination test had a sensitivity of 30% and 78%, and a specificity of 89% and 98% respectively compared with culture. The sensitivity of the latex agglutination test was higher in cases of premature rupture of membranes (90%), presumed chorioamnionitis (86%), presumed post-partum endometritis (86%) and presumed salpingitis (87%). This latex agglutination test appears to be useful for identifying patients who are heavily colonized with Streptococcus agalactiae and are at a high risk of infection.