Chlamydia trachomatis infections, which most frequently are asymptomatic, are major public health concerns globally. The 2015 European C. trachomatis guideline provides: up-to-date guidance regarding broader indications for testing and treatment of C. trachomatis infections; a clearer recommendation of using exclusively-validated nucleic acid amplification tests for diagnosis; advice on (repeated) C. trachomatis testing; the recommendation of increased testing to reduce the incidence of pelvic inflammatory disease and prevent exposure to infection; and recommendations to identify, verify and report C. trachomatis variants. Improvement of access to testing, test performance, diagnostics, antimicrobial treatment and follow-up of C. trachomatis patients are crucial to control its spread. For detailed background, evidence base and discussions, see the background review for the present 2015 European guideline on the management of Chlamydia trachomatis infections (Lanjouw E, et al. Int J STD AIDS. 2015).

Summary: This guideline aims to provide comprehensive information regarding the management of infections caused by Chlamydia trachomatis in European countries. The recommendations contain important information for physicians and laboratory staff working with sexually transmitted infections (STIs) and/or STI-related issues. Individual European countries may be required to make minor national adjustments to this guideline as some of the tests or specific local data may not be accessible, or because of specific laws.

SummaryChlamydia trachomatis infections are major public health concerns globally. Of particular grave concern is that the majority of persons with anogenital Chlamydia trachomatis infections are asymptomatic and accordingly not aware of their infection, and this silent infection can subsequently result in severe reproductive tract complications and sequelae. The current review paper provides all background, evidence base and discussions for the 2015 European guideline on the management of Chlamydia trachomatis infections (Lanjouw E, et al. Int J STD AIDS 2015). Comprehensive information and recommendations are included regarding the diagnosis, treatment and prevention of anogenital, pharyngeal and conjunctival Chlamydia trachomatis infections in European countries. However, Chlamydia trachomatis also causes the eye infection trachoma, which is not a sexually transmitted infection. The 2015 European Chlamydia trachomatis guideline provides up-to-date guidance regarding broader indications for testing and treatment of Chlamydia trachomatis infections; clearer recommendation of using validated nucleic acid amplification tests only for diagnosis; advice on (repeated) Chlamydia trachomatis testing; recommendation of increased testing to reduce the incidence of pelvic inflammatory disease and prevent exposure to infection and recommendations to identify, verify and report Chlamydia trachomatis variants. Improvement of access to testing, test performance, diagnostics, antimicrobial treatment and follow-up of Chlamydia trachomatis patients are crucial to control its spread.

BackgroundChlamydia trachomatis is the most prevalent bacterial sexually transmitted infection (STI) worldwide. A strong link between C. trachomatis serogroup/serovar and serological response has been suggested in a previous preliminary study. The aim of the current study was to confirm and strengthen those findings about serological IgG responses in relation to C. trachomatis serogroups and serovars.MethodsThe study population (n = 718) consisted of two patient groups with similar characteristics of Dutch STI clinic visitors. We performed genotyping of serovars and used titre based and quantitative commercially available ELISA kits (medac Diagnostika) to determine specific serum IgG levels. Optical density (OD) values generated by both tests were used to calculate the IgG titres (cut-off 1:50). Analyses were conducted stratified by gender.ResultsWe observed very significant differences when comparing the median IgG titres of three serogroups, B, C and I: in women for B vs. C: p < 0.0001 (median titres B 200 vs. C <50); B vs. I: p < 0.0001 (200 vs. 50), and in men for B vs. C: p = 0.0006 (150 vs. <50); B vs. I: p = 0.0001 (150 vs. <50); C vs. I was not significant for both sexes. Serovars D and E of serogroup B had the highest median IgG titres compared to the other serovars in both men and women: 200 and 200 vs. ≤ 100 for women and 100 and 200 vs. ≤ 75 for men, respectively.ConclusionsThis study shows that B group serovars induce higher serological responses compared to the C and I group serovars in vivo in both men and women.

Results Sixty-six (49%) women seroconverted; of 54 tested on day zero, 46 (85%) were positive and 8 (15%) were negative and then positive when next tested (median 90 days). Of 12 seroconverters not tested on day zero, 11 (92%) were seropositive when next tested (median, 157 days). Nineteen (28%) of 69 non-seroconverters had no IgG testing beyond day zero and could not be assessed for delayed seroconversion. Of 52 seroconverters with subsequent testing, 27 (52%) remained persistently IgG-positive through the last test (median 248 days after seroconversion). Persistent IgG-positivity occurred in 61% (22/36) of those who were ever cHSP60-positive and 37% (6/16) of those who were not (NS), and in 56% (19/34) of those with only one Ct-PCR-positive visit and 50% (9/18) of those with more than one Ct-PCR-positive visit (NS). Conclusions Anti-MOMP IgG antibodies developed in half of women with incident Ct infection and persisted in half of them. Although persistence was more common in those who were cHSP60-positive (suggesting complicated infection), the difference was not statistically significant. Background Chlamydia trachomatis infection increases above gonorrhoea and syphilis, ranking first among the STDs. Molecular epidemiological researches have shown the predominant genotypes vary between regions, periods and population subgroups. However, serovars E, D and F are the most prevalent serovars. It is unclear whether the epidemiological characteristics were contributed to geography or pathogenicity. We explored the pathogenic diversity of different C. trachomatis serovars in mouse genital infection. Methods One hundred of female BALB/C mice were divided into serovar E, F, H, J and K groups. The mice in study group treated by medroxyprogesterone acetate were inoculated 10 7 C. trachomatis into genital tract. C. trachomatis was detected by culture, direct immunofluorescence assay (DFA) and PCR in the cervicovaginal secretion. On the days 7 and 35 after inoculation, inflammation of the cervix, uterus and oviduct were examined by HE stain, and expressions of cHSP60 and CPAF in the uterus and fallopian tube were detected by ELISA. Results The inflammatory of the cervical mucosa was more severe in serovar E group compared with J, K and H groups on day 7 postinoculation. Accordingly, cHSP60 and CPAF expression increased significantly in E group compared with other experimental and control groups. On day 35 post-inoculation, the histo-pathological changes of the genital tract were obvious in J, K and H groups, characterised with uterine swelling, pyometra and effusion, fallopian expansion, hydrops, fibrosis and stenosis. cHSP60 and CPAF expression in H group was superior to that in other groups. Positive correlation between cHSP60 and CPAF expression was present on day 7 and 35 post-inoculation, respectively. Conclusion There existed pathogenic diversity among different C. trachomatis servoars in mouse genital infection. The expression of inflammatory cytokines of cHSP60 and CPAF during Chlamydial infection might partially ...