Streptococcus agalactiae and Chlamydia trachomatis detection in women without symptoms of infection

Chlamydia trachomatis (C. trachomatis) and Streptococcus agalactiae (GBS) may be present in the female cervical canal without any symptoms of infection. Chronic chlamydial infections lead to many serious complications and perinatal infections, while the presence of GBS is a reservoir for infections of newborns or invasive streptococcal infection in adults.

To examine healthy women for C. trachomatis without symptoms from the reproductive system, assess the frequency of asymptomatic infections, detect GBS in the cervical canal, demonstrate differences in drug susceptibility, and determine the serotype of S. agalactiae strains and correlations among the ones present in the cervical canal.

A total of 315 cervical swabs were collected for genetic and microbiological analysis for the presence of C. trachomatis and S. agalactiae. Latex and diffusion-disk methods were used to determine the serotype and susceptibility of streptococci.

Ten out of 315 women (3.2%) were C. trachomatis-positive. Using traditional methods of microscopy, culture and serology, 42 strains (13.3% of the subjects) obtained from patients were identified as S. agalactiae and further analyzed. The most common serotypes identified were II (18/42, 42.9%), V (11/42, 26.2%) and III (10/42, 23.8%). The less common serotypes found were VII (2/10, 4.8%), and Ib (1/10, 2.4%); no Ia, IV or VII serotypes were found. All the strains were susceptible to penicillin, while 71.4% of them were susceptible to erythromycin and 81.0% were susceptible to clindamycin. Seven isolates (16.7%) were concomitantly resistant to erythromycin and clindamycin.

Chlamydia trachomatis was confirmed in 3.2% of the respondents, and GBS was found in 13.3%, despite a lack of symptoms of infection. The incidence of C. trachomatis infections and GBS colonization in Poland is similar to those in other European countries.