孕期沙眼衣原体感染与妊娠结局的关系

目的研究孕期沙眼衣原体(Chlamydia trachomatis,CT)与妊娠结局的关系.方法120例CT感染给予治疗的孕妇为A组;选择在年龄、孕周与之匹配因故未治疗的57例CT感染孕妇为B组;同期行围产监测的120例正常孕妇为C组.比较不良妊娠结局及宫内感染率.结果B组的自然流产、胎膜早破、早产、低体重儿、产褥感染、新生儿结膜炎、新生儿肺炎的发生率高于C组,P＜0.05,差异有显著性意义.A组与B组相比,其妊娠结局好转、宫内感染率下降,P＜0.05,差异有显著性意义.结论孕期CT感染可造成不良妊娠结局,治疗降低了宫内垂直传播率,应在孕前、孕早期常规筛查以便早诊早治从而改善妊娠结局.     

Chlamydia trachomatis infection of human trophoblast alters estrogen and progesterone biosynthesis: an insight into role of infection in pregnancy sequelae

The trophoblast cells are in direct contact with endometrial tissues throughout gestation, playing important early roles in implantation and placentation. The physiologic significance and the operating mechanisms involved in probable altered trophoblast functions following Chlamydia trachomatis infection were investigated to determine if C. trachomatis initiates productive infection in trophoblast, effects of such event on the biosynthesis of cholesterol and its derivatives estrogen and progesterone; and the regulator of the biosynthesis of these hormones, human chorionic gonadotropin. Chlamydia trachomatis exhibited productive infection in trophoblast typified by inclusion formation observed when chlamydia elementary bodies were harvested from trophoblast and titrated onto HEp-2 cells. Assessment of the status of C. trachomatis in trophoblast showed a relative increase in protein of HSP-60 compared with MOMP, features suggestive of chlamydial chronicity. There was a decrease in cellular cholesterol of chlamydia infected trophoblast and a down regulation of HMG-CoA reductase. The levels of estrogen and progesterone were decreased, while the expression of aromatase and adrenodoxin reductase was up regulated. Also, there was a decrease in human chorionic gonadotropin expression. The implications of these findings are that C. trachomatis infection of trophoblast may compromise cellular cholesterol biosynthesis, thus depleting the substrate pool for estrogen and progesterone synthesis. This defect may impair trophoblast functions of implantation and placentation, and consequently affect pregnancy sequelae.     

Cross-reactivity between Chlamydia trachomatis heat shock protein 10 and early pregnancy factor

Chlamydia trachomatis heat shock protein 10 (Chsp10) is associated with chronic genital tract infection with C. trachomatis. Chsp10 is homologous to human chaperonin 10 (Cpn10) and early pregnancy factor (EPF), a form of human Cpn10 that is specifically secreted at the start of pregnancy. We investigated cross-reactions between serum anti-Chsp10 antibodies and anti-EPF antibodies in pregnant and nonpregnant patients. Pregnancy was found to be associated with the presence of anti-EPF antibodies, which are specifically induced in pregnant women with a history of C. trachomatis infection, and with the presence of serum anti-Chsp10 antibodies. We also found that infertility was associated with the presence of anti-Chsp10 and anti-EPF antibodies. The HLA class II haplotype DR8 DQ4 was associated with the presence of anti-Chsp10 antibodies but not of anti-EPF antibodies.     

Serum IgM to Chlamydia trachomatis in pregnancy: its usefulness for screening

Asymptomatic infection with Chlamydia trachomatis represents an important health problem. A non-invasive diagnostic test to screen pregnant women is needed that is cost effective and can be used widely, especially in developing countries. In this setting, quantitation of antichlamydial IgM antibodies may offer an additional strategy for the control of C. trachomatis infection. The aim of this prospective study is to evaluate the quantitation of serum antichlamydial IgM antibodies, based on absorbance (A) values, in pregnant women for the prediction of C. trachomatis infection. Serum samples from a cohort of 148 pregnant women (first to third trimesters; age range: 18-35 years) presenting to the antenatal department at Safdarjang Hospital were tested for IgM antibodies specific to C. trachomatis by an enzyme-linked immunosorbent assay (ELISA) kit (Novum Diagnostics, Germany). Co-infection with other STD pathogens was ruled out. In this cohort, 85 (57.4%) pregnant women were found to be positive for IgM antibodies to C. trachomatis. Based on the cut-off value of the ELISA test (calculated as 0.558), pregnant women with an A value between 0.558 and 0.999 and those with a value > 1.000 were categorised as low positive (LP, n=41) and high positive (HP, n=44), respectively. The differences in mean A values for the LP versus negative groups (0.7504 versus 0.2249, P<0.05) and the HP versus negative groups (1.5353 versus 0.2249, P<0.05) were statistically significant. Maximum seroprevalence (44.4%, P<0.05) was found among those in the HP group in the first trimester of pregnancy. Multigravidae (34.4%, P<0.5) and multiparous (34.9%, P<0.5) pregnant women in the HP group were at an increased risk of chlamydial infection. As overall results indicated that pregnant women in the HP group were at higher risk, we stress the importance of large-scale screening of pregnant women for C. trachomatis infection, particularly in developing countries where sophisticated techniques for collection/diagnosis are as yet unavailable.     

Specific-pathogen-free pigs as an animal model for studying Chlamydia trachomatis genital infection

The purpose of the present study was to evaluate pigs as a large-animal model for female genital infection with two Chlamydia trachomatis human serovar E strains. Sixteen-week-old specific-pathogen-free female pigs (gilts) were intravaginally infected with the trachoma type E reference strain Bour or the urogenital serovar E strain 468. Several conclusions can be drawn from our findings on the pathogenicity of a primary C. trachomatis genital infection in gilts. First of all, we demonstrated that the serovar E strains Bour and 468 could ascend in the genital tract of gilts. The serovar E strains could replicate in the superficial columnar cervical epithelium and in the superficial epithelial layer of the uterus, which are known to be the specific target sites for a C. trachomatis genital infection in women. Second, inflammation and pathology occurred at the replication sites. Third, the organisms could trigger a humoral immune response, as demonstrated by the presence of immunoglobulin M (IgM), IgG, and IgA in both serum and genital secretion samples. Our findings imply that the pig model might be useful for studying the pathology, pathogenesis, and immune response to a C. trachomatis infection of the genital system.     

沙眼衣原体感染诱导精子凋亡

目的:研究精液沙眼衣原体(CT)感染对男性生殖的影响.方法:选择精液CT阳性的男性不育者57例作为CT阳性组,另选择正常对照组15例.检测精液常规,免疫层析法检测CT感染情况,末端脱氧核苷酸转移酶(TdT)介导的TUNEL法检测凋亡精子.结果: CT阳性组精子凋亡率为33.03%±14.98%,正常对照组为9.68%±2.78%,CT阳性组精子凋亡率明显增高.结论:精液CT感染诱导精子凋亡率增加,精液沙眼衣原体感染是引起男性不育的原因之一.     

Value of screening for oro-pharyngeal Chlamydia trachomatis infection.

AIMS--To determine whether oro-pharyngeal colonisation by Chlamydia trachomatis occurs in patients at risk of genital chlamydia infection; to determine whether screening pharyngeal specimens by polymerase chain reaction (PCR) increases detection of C trachomatis compared with isolation and the immune dot blot test; and to correlate the detection of C trachomatis and Neisseria gonorrhoeae in the pharynx with a history of oro-genital contact. METHODS--Thirteen homosexuals and 11 heterosexuals were included in the study. Urogenital and pharyngeal specimens were tested for C trachomatis and N gonorrhoeae using standard clinical diagnostic procedures. Two different PCR methodologies were also used to detect C trachomatis in the pharyngeal specimens. Results were correlated with the mode of sexual practice. RESULTS--Oro-genital sexual contact was practised by 64.9% (72/111) of heterosexuals in addition to penetrative penovaginal intercourse. Additionally, 62.1% (77/124) of all patients did not use any form of barrier protection. Of those who admitted to oro-genital sexual contact, 17.6% of patients with a genital chlamydial infection and 36.4% of those with genital gonorrhoea also had asymptomatic pharyngeal colonisation. C trachomatis was detected in three of 124 (2.4%) pharyngeal specimens by PCR which were reported as negative by chlamydial culture; one was positive by the immune dot blot test. CONCLUSION--The majority of patients practised unprotected oro-genital contact and significant pharyngeal colonisation by C trachomatis and N gonorrhoeae occurred if genital infection was present. Despite the use of PCR in a population at high risk of sexually transmitted disease, the prevalence of chlamydia in the pharynx was very low. This indicates that transmission of C trachomatis to the oro-pharynx does not pose a serious health risk and that screening of patients for oro-pharyngeal C trachomatis is not worthwhile.     

A study of prevalence of Chlamydia trachomatis infection in women with first trimester pregnancy losses

The study included 125 patients in the first trimester of pregnancy, who were divided into group A (50 control subjects with normal intrauterine pregnancy), Group B (50 patients with spontaneous abortion), group C (25 patients with ectopic pregnancy). All the patients were investigated including routine blood and urine tests and special tests related to the cause of pregnancy loss. The patients were tested for IgG antibodies to Chlamydia trachomatis by ELISA technique and conjunctival smear were tested for presence of inclusion bodies to C. trachomatis. It was concluded that C. trachomatis is one of the important cause of spontaneous abortion and ectopic pregnancy. It is highly prevalent in our population, the prevalence being 10% in group A, 26% in group B, 28% in group C. Conjunctival smear showed presence of inclusion bodies in 0.8% patients. With abortions then risk of lower genital tract chlamydia infection spreading to upper genital tract increases. ELISA for C. trachomatis should be done when women are being investigated for the cause of spontaneous abortion and ectopic pregnancy.     

Prevalence and risk factors for Chlamydia trachomatis infection in adolescent females and young women in central Brazil

In order to determine the prevalence and risk factors for Chlamydia trachomatis infection in adolescent females and young women in central Brazil, 296 subjects attending two public health services were evaluated. The overall prevalence of C. trachomatis infection, as determined using polymerase chain reaction, was 19.6% (95% confidence interval [CI], 15.3–24.7). In multivariate analysis, young age (odds ratio [OR]_adjusted 2.32, 95%CI 1.1–4.8, p<0.05) and having 2–3 (OR_adjusted 3.41, 95%CI 1.6–6.3, p<0.05) or ≥4 sexual partners in life (OR_adjusted 3.10, 95%CI 1.1–6.3, p<0.05) were factors significantly associated with chlamydial infection. In conclusion, the prevalence of C. trachomatis infection was high in the studied population and risk factors were related to age and sexual behavior.     

Local markers for prediction of women at higher risk of developing sequelae to Chlamydia trachomatis infection

PROBLEM: Chlamydial infections are often associated with various fertility-related disorders. Serological prediction of these has limitations, as they do not differentiate between past and current infections. Thus, we looked for local markers that could predict more precisely women at higher risk of developing severe complications. METHOD OF STUDY: A total of 320 Chlamydia trachomatis positive women with or without fertility disorders were tested for the prevalence of immunoglobulin A antibodies to synthetic peptides of chlamydial heat-shock protein 60 (cHSP60) and cHSP10 along with cervical interferon-gamma (IFN-gamma) and serum C-reactive protein (CRP) levels. RESULTS: Positive IFN-gamma level was the single best predictor for fertility disorder [odds ratio (OR) 15.4]. The predictive value of IFN-gamma could be significantly improved only by the addition of CRP test (OR 37.9). CONCLUSION: Positive IFN-gamma levels in cervical washes along with elevated CRP levels could be used to predict women who are at higher risk of developing fertility disorders.     

Chlamydia trachomatis infection: host immune responses and potential vaccines

Chlamydia trachomatis causes genital tract infections that affect men, women, and children on a global scale. This review focuses on innate and adaptive immune responses in the female reproductive tract (FRT) to genital tract infections with C. trachomatis. It covers C. trachomatis infections and highlights our current knowledge of genital tract infections, serovar distribution, infectious load, and clinical manifestations of these infections in women. The unique features of the immune system of the FRT will be discussed and will include a review of our current knowledge of innate and adaptive immunity to chlamydial infections at this mucosal site. The use of animal models to study the pathogenesis of, and immunity to, Chlamydia infection of the female genital tract will also be discussed and a review of recent immunization and challenge experiments in the murine model of chlamydial FRT infection will be presented.     

Cultural method for large-scale screening for Chlamydia trachomatis genital infection.

Idoxuridine-treated McCoy cells grown as monolayers in 96 well microplates provide a convenient method for the isolation of Chlamydia trachomatis. Staining of infected monolayers with periodic acid-Schiff reagent (PAS) allows easy recognition of C trachomatis inclusions without the need for dark-ground microscopy. By this method 384 clinical specimens can be examined concurrently. It is sufficiently sensitive to form the basis of a chlamydial culture service for patients attending Sexually Transmitted Diseases (STD) Clinics.     

Simultaneous Chlamydia trachomatis and HPV infection in pregnant women

Pregnancy is associated with HPV infection and with Chlamydia trachomatis (CT) infection mostly due to the natural immunosuppression. In addition, pregnancy associated to CT infection can lead to adverse conditions to the woman and fetus, and CT is also believed to be a co‐factor in human immunodeficiency virus infection and HPV‐induced cervical cancer. The aim of this study was to establish the odds ratios (OR) of CT infection in to HPV‐infected pregnant women and vice versa of women stratified by age (<25 years) and marital status. This work is part of a national multicentric transversal study carried out in six Brazilian cities supported by the Ministry of Health of Federal Government of Brazil in 2003. Cervical scrapes of 371 pregnant women were sampled. We performed a hybrid capture‐2 technique to diagnose these samples on HPV and CT infection, and the women responded a questionnaire. Significant association was observed between nonstable marital status and hr‐HPV infection [OR = 2.61 (1.38–4.97) P = 0.003)], and age <25 years old [OR = 2.26 (1.09–4.71) P = 0.029]. Nonstable marital status was also associated with lr‐HPV infection [OR = 2.67 (1.59–4.50) P < 0.001), and age <25 years old [OR = 2.55 (1.51–4.32) P < 0.001). Fifty of the 371 pregnant women were infected with hr‐HPV (13.5%) and 111 (30.0%) were infected with lr‐HPV. The coinfections of HPV and CT were found in 31 women, that is, 8.36% of the pregnant women (P < 0.001). The high rate of simultaneous CT and HPV infection in pregnant women favors the recommendation to screen pregnant women for both CT and HPV. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.     

Experimental Chlamydia trachomatis infection causes apoptosis in human sperm

BACKGROUND: Chlamydia trachomatis is responsible for a widespread sexually transmitted infection. In men, it is associated with a wide clinical spectrum causing infertility. Furthermore, C. trachomatis serovar E infection decreases motility and increases the number of non-viable sperm. No other effects of C. trachomatis have been reported on sperm despite the crucial role of DNA integrity for sperm function. The aim of this study was to investigate the effects of C. trachomatis on sperm apoptosis. METHODS: Sperm from eight normozoospermic men were incubated with increasing concentrations of C. trachomatis serovar E elementary bodies (EB) for 6 and 24 h. Sperm were then collected to evaluate phosphatidylserine (PS) membrane translocation and DNA fragmentation by Annexin V-propidium iodide staining, TUNEL assay and flow cytometry. RESULTS: After 6 h of incubation, C. trachomatis had no effect on the percentage of sperm showing PS externalization. However, a significant effect on this parameter was observed after 24 h. C. trachomatis also significantly increased the number of sperm with DNA fragmentation both after 6 and 24 h of incubation. CONCLUSIONS: C. trachomatis causes sperm PS externalization and DNA fragmentation. These effects may explain the negative direct impact of C. trachomatis infection on sperm fertilizing ability.