Screening for Chlamydia trachomatis in subfertile women

Chlamydia trachomatis is the most common sexually transmitted disease in the UK and Europe. The majority of female infections are asymptomatic and recognized sequelae include pelvic inflammatory disease, infertility, and ectopic pregnancy. Women with chlamydial infection who undergo uterine instrumentation are recognized to be at risk of ascending infection. Most patients attending for infertility investigations and treatment will undergo some form of uterine instrumentation. Published data regarding the prevalence of chlamydial infection in the subfertile are few and conflicting. In this study, more than 400 consecutive women presenting for infertility investigation and treatment at a single regional fertility centre were screened for Chlamydia: Half were screened using enzyme immunoassay (EIA) and half by ligase chain reaction (LCR). Prevalence by diagnostic test was 0% with EIA and 1.9% with LCR. Overall, the low prevalence was at least partly explained by older age. Until more evidence comes from studies testing consecutive subfertile patients both with EIA and a DNA amplification method such as LCR, centres using EIA should consider using prophylactic antibiotics prior to uterine instrumentation.     

Immunology: Circulating antibodies to Chlamydia trachomatis in women: relationship to antisperm and antichiamydial antibodies in semen of male partners

The relation between antibodies to Chlamydia trachomatis andspermatozoa in sera of 112 asymptomatic female partners of infertilecouples with no history of C.trachomatis infections and antichlamydialantibodies in semen or antisperm antibodies on ejaculated spermatozoaof their male partners was examined. Samples were tested forimmunoglobulin (Ig)A and IgG antibodies to C.trachomatis byenzyme-linked immunosorbent assay; antisperm antibodies in seraand on motile spermatozoa were assayed by immunobead binding.IgG antibodies to C.trachomatis were detected in 24 (21.4%)of the women; only five (4.5%) women were positive for antichlamydialIgA. Antichlamydial IgG was detected in sera from 10 (40.0%)of 25 women whose partners had antichlamydial IgA in semen asopposed to 14 (16.1%) of 87 women whose partners' semen werenegative for this antibody (P=0.02). Similarly, antichlamydialIgG was detected in sera from five (50%) of 10 women whose partnershad antichlamydial IgG in semen as opposed to 19 (18.6%) of102 women whose partners' semen lacked this antibody (P=0.03).There was no relation between antichlamydial antibodies in womenand circulating antichlamydial antibodies in men. A strong correlation(P=0.001) was observed between IgG antichlamydial antibodiesin a woman's serum and antisperm antibodies on ejaculated spermatozoaof her partner [8 of 14 (57.1%) versus 16 of 98 (163%)]. Conversely,antichlamydial antibodies in a woman's serum was unrelated tothe presence of antisperm antibodies in either her own serumor her partner's serum. The data demonstrate that chlamydialinfections of the male genital tract, which are associated withantisperm antibody formation on ejaculated spermatozoa, arelikely to be transmitted to the female partner. In contrast,the presence of antichlamydial antibodies in sera does not necessarilyappear to indicate an infection of the genital tract and isnot associated with the heterosexual transmission of C.trachomatis.     

Relationship between an asymptomatic male genital tract exposure to Chlamydia trachomatis and an autoimmune response to spermatozoa

The relationship between a localized genital tract humoral immuneresponse to Chlamydia trachomatis and the presence of antispermantibodies on the surface of motile spermatozoa in the ejaculatewas examined in 227 asymptomatic male partners of infertilecouples with no history of exposure to C.trachomatis. Semenand serum samples were assayed for immunoglobulin (Ig) A andIgG antibodies to C.trachomatis by enzyme-linked immunosorbentassay employing a recombinant Chlamydia-specific lipopolysaccharidefragment (Medac, Hamburg, Germany), while motile spermatozoawere tested for bound autoantibodies by immunobead binding.Semen samples from 24.7 and 10.9% of the men were positive forIgA and IgG antibodies to C.trachomatis respectively. In comparison,antichlamydial IgA was less prevalent in sera (14.5%) than insemen (P = 0.01), while antichlamydial IgG was most prevalent(21.5%) in sera (P =0.003). In 75.0% of the men with antichlamydialIgA in their semen, this antibody was undetectable in sera obtainedat the time of semen collection. Conversely, 84.0% of the menwith seminal antichlamydial IgG were also IgG seropositive.Antisperm IgG and/or IgA were detected on motile spermatozoafrom 16.3% of the men; their occurrence was strongly correlatedwith the presence of antichlamydial IgA in semen (P < 0.0001).Weaker associations between antisperm antibodies and eitherseminal IgG antibodies to C.trachomatis (P = 0.01) or circulatingIgA and IgG antichlamydial antibodies (P = 0.03) were also observed.Men with antichlamydial IgA in their semen had a lower mediansperm count (82 versus 144 x 10⁶/ml) than those men without(P = 0.003); sperm morphology and motility were comparable inboth groups. These data suggest that asymptomatic male genitaltract exposure to C.trachomatis is a frequent event among thispopulation and that the presence of a humoral immune responseto this organism is correlated with the development of an autoimmuneresponse to spermatozoa.     

Chlamydia trachomatis in subfertile women undergoing uterine instrumentation. The clinician's role

Most women attending a fertility clinic will undergo uterine instrumentation either diagnostically and/or therapeutically. This places them at potential risk of chlamydial pelvic inflammatory disease. Clinicians remain unclear about the roles of screening, serology and prophylactic antibiotics. A review of the evidence suggests that women <25 years and those older with risk factors, men with risk factors and gamete donors should have their lower genital tract screened for Chlamydia trachomatis by a sensitive test. More information is required before screening men by age can be recommended. Serology in its present form cannot be advocated as a screening tool. Those women with a past history of chlamydial morbidity or a diagnosis of tubal pathology should, in addition to screening, be covered with prophylactic antibiotics when undergoing uterine instrumentation. The partner should be screened for sexually transmitted infections. Non-selective use of prophylactic antibiotics serves only to increase the problem of antibiotic resistance and maintain the bacterial load of chlamydia in the community.     

沙眼衣原体诊断技术研究进展

沙眼衣原体（Ct）是一种特殊的病原体,具有与革兰氏阴性细菌相似的细胞壁,含有DNA和RNA两种类型的核酸,严格寄生于宿主细胞内,沙眼衣原体是一种能够通过滤器,以二分裂方式繁殖的原核细胞型微生物.它具有两种形态：在细胞外具有高度传染性的为原体 在细胞内进行复制、无传染性的为始体.它可以引起非淋球菌尿道炎等许多泌尿生殖道相关疾病,近年来其感染率和危害性已超过淋病奈瑟菌而居性传播疾病之首,眼部衣原体侵入人体眼结膜和角膜引起沙眼和包涵体结膜炎,是世界范围致盲的首要病因.约80%的被感染女性无临床症状,感染反复迁移,造成病理改变,可导致复杂的并发症.因此,早期、简便、快速、特异地发现Ct,对临床的诊断,疾病的早期治疗和预防其流行等具有重要的意义.目前,对沙眼衣原体的诊断方法主要有培养法,免疫学法和分子生物学法.     

Value of papanicolaou smear in detection of Chlamydia trachomatis infection

This study was undertaken to assess the value of Papanicolaou smear for the diagnosis of Chlamydia trachomatis infection. The study was both retrospective (groups I and II) and prospective (group III). Group I consisted of 41 smears with cytomorphological changes proposed by Gupta, Kiviat, or Shiina. Group II was a control group, consisting of 30 cytologically normal smears. All these smears were subjected to specific immunofluorescent (IF) staining under identical conditions to confirm the diagnosis. In group III, 40 consecutive duplicate cervical smears were collected from patients attending the Sexually Transmitted Disease Clinic. One smear was routinely examined, and the specific IF staining was done on the other smear. The results in all the three groups were analysed. It was concluded that Papanicolaou smear is not useful in the detection of Chlamydia trachomatis infection.     

The value of Chlamydia trachomatis antibody testing as part of routine infertility investigations

Laparoscopy is considered the gold standard for the evaluation of tubal disease but it is an invasive and costly procedure. Chlamydia trachomatis antibody testing is simple and inexpensive and causes minimal inconvenience to the patient. Using the micro-immunofluorescence technique we assessed the significance of positive serology. There was a marked association between the titre and the likelihood of tubal damage. In the group with low titres (1 in 32) there was only a 5% incidence of tubal damage; however, there was a progressive increase in the incidence of tubal damage in those with higher titres. Twenty out of 57 patients with titres higher than 1 in 32 had tubal damage (35%). The difference between the two groups was statistically significant (P < 0.0001, chi(2) test). By using C. trachomatis antibody testing more widely it may be possible to reduce the number of laparoscopies performed. It should therefore become an integral part of the fertility work-up.     

The value of Chlamydia trachomatis antibody testing in predicting tubal factor infertility

BACKGROUND: The objective of the present study was to compare the likelihood of abnormal Chlamydia trachomatis antibody test results with that of abnormal hysterosalpingography (HSG) test results in patients with tubal factor infertility. METHODS: Anti-C. trachomatis immunoglobulin G antibodies were determined prospectively in 295 infertility patients by means of an indirect fluorescent antibody technique. In 48 of the 295 patients both HSG and laparoscopy with chromotubation were performed. The results of C. trachomatis antibody testing were compared with the results of HSG with respect to their predictive value of tubal factor infertility. Likelihood ratios for abnormal C. trachomatis antibody and HSG test results were determined in infertility patients, as assessed by laparoscopy. RESULTS: The positive likelihood ratio for C. trachomatis antibody testing was 1.8. This was comparable with the HSG, which had a positive likelihood ratio of 1.7. CONCLUSIONS: The predictive value of C. trachomatis antibody testing was equal to that of HSG, but ratios of 1.7 and 1.8 indicate a poor test, so both C. trachomatis antibody testing and HSG have a poor predictive value. C. trachomatis antibody testing causes minimal inconvenience to the patient, in contrast to HSG, and therefore should be maintained in infertility examinations.     

Usefulness of transvaginal hydrolaparoscopy in investigating infertile women with Chlamydia trachomatis infection

BACKGROUND: A new technique called transvaginal hydrolaparoscopy (THL) was recently developed for the exploration of the tubo-ovarian structures in infertile patients without obvious pelvic pathology. This study was performed to investigate the usefulness of THL to evaluate Chlamydia trachomatis tubal infertility. METHODS: Forty-one women with primary and secondary infertility participated in this study. Fourteen had past C. trachomatis infection. In 38 (92.7%) of the 41, access to the pouch of Douglas was obtained. In total, 71 (93.4%) out of 76 adnexa were clearly visualized. Thirty-seven patients were analysed and compared their tubal passages and peritubal adhesions using both hysterosalpingography (HSG) and THL. Twenty-four tubes from 14 patients with past C. trachomatis infection and 44 tubes from 23 patients without a history of C. trachomatis infection were compared. RESULTS: For the diagnosis of the tubal passage, there were no significant differences in the discrepancy rates between HSG and THL, in patients with and without past C. trachomatis infection. In 14 (58.3%) of the 24 tubes from patients with past C. trachomatis infection and in eight (18.2%) of the 44 tubes from patients without infection, peritubal adhesion was diagnosed only by THL. There was a significant difference in the discrepancy rates of the diagnosis of peritubal adhesion between HSG and THL in the two groups (P = 0.0007 ). CONCLUSIONS: These results suggest that C. trachomatis infection is highly associated with peritubal adhesion which is difficult to diagnose by HSG. Therefore, in C. trachomatis antibody-positive patients, exclusion of tubal pathology by THL or standard laparoscopy should be carried out to consider appropriate treatments. Although THL is not a substitute for laparoscopy, it can be proposed as a first line procedure in the early stages of the infertility investigation.     

沙眼衣原体套式（Nested）PCR检测研究

本文报告沙眼衣原体（ＣＴ）的套式（Ｎｅｓｔｅｄ）ＰＣＲ检测方法，本方法ＣＴ隐匿性质粒为靶基因，外套引物采用国外学者所报告灵敏度和特异性较高的序列，内套引物自行设计，经方法学考核表明本法灵敏度和特异性极高。１４６例临检标本套式ＣＴ，ＰＣＲ阳性检出率为３６．３％而市售ＰＣＲ试剂盒（其引物序列与本文外套引物相同）阳性检出率仅为４．１％，前者明显高于后者（Ｐ〈０．０１）。     

Immunology: Chlamydial immunoglobulin IgG and IgA antibodies in serum and semen are not associated with the presence of Chlamydia trachomatis DNA or rRNA in semen from male partners of infertile couples

The role of Chlamydia (C.) trachomatis in male infertility iscontroversial. The objective of this study was to determinethe prevalence of asymptomatic C.trachomatis infections in malepartners of infertile couples, and to compare this result withthe presence of chlamydial antibodies in serum and semen. C.trachomatiswas detected in five of 50 semen specimens (10%) by either polymerasechain reaction for C.trachomatis DNA or direct DNA probing forC.trachomatis rRNA. There was no association between the detectionof C.trachomatis in semen and the presence of chlamydial antibodiesin serum or semen. Chlamydial serum antibodies were neitherassociated with antisperm serum antibodies nor with pathologicalstandard semen parameters. These results indicate that the assessmentof chlamydial immunoglobulin IgG and IgA antibodies in serumor semen is of limited use in male infertility work-up, in contrastto its significance in female tubal infertility. The presenceof C.trachomatis in semen emphasizes the potential risk of transmissionduring artificial insemination and other assisted reproductivetechniques, and underlines the importance of sensitive directdetection methods in this group of patients.     

An experimental model for salpingitis due to Chlamydia trachomatis and residual tubal infertility in the mouse

A mouse model of salpingitis and subsequent tubal infertility induced by a human strain of Chlamydia trachomatis has been studied. C3H/He female mice were inoculated into the ovarian bursa. Some of the mice (six infected, five controls) were killed on days 15 and 23 and the remaining animals (10 infected, 10 controls) were mated on day 15. On day 15, the infection was maximal with intratubal inflammation, elevated antichlamydial antibody titre and positive cultures in 12 cases out of 16. After 19 weeks of housing with the male, the proportion of fertilized females was significantly lower in the infected group (20% versus 100% in the control group P less than 0.01). In the killed mice, hydrosalpinx and or tubal occlusion were noted at this time in nine cases out of 10, despite an apparent bacteriological healing.     

Ultrastructural observations on the entry of Chlamydia trachomatis into human spermatozoa

Chlamydia trachomatis infections are an important problem inhuman reproduction and family planning. In this study, the significanceof chlamydial infection in male infertility and artificial inseminationhas been investigated. Electron microscope observations on maleejaculates have revealed the presence of the elementary andreticulate body forms of C.trachomatis in spermatozoa. Furthermore,the entry of the elementary body into the human spermatozoonhead has been demonstrated. After the passage of the infectiouselementary body into the nucleus, all stages of reticulate bodyformation in the head of the spermatozoon were detected. Accordingto ultrastructural findings, C.trachomatis not only adheredto but also penetrated into the tail structure. Thus two differentfunctional and morphological forms of C.trachomatis can infectand be transmitted by spermatozoa and may cause infertility.     

Use of the ligase chain reaction on urine of men and their female sexual partners for detection of genital Chlamydia trachomatis infection

Objective: The purpose of the present study was to evaluate an in vitro DNA amplification assay named the ligase chain reaction (LCR) for the detection of Chlamydia trachomatis cryptic plasmid DNA in urine from men and women, in comparison with urethral swab culture in men and cervical swab culture in women.
Methods: 591 patients (394 men with urethritis and 197 female sex partners) attending a center for sexually transmitted diseases in northern Italy between January 1994 and January 1995 were enrolled in this study. A cervical swab was collected from women and a urethral swab from men for standard tissue cell culture. From each patient 20 mL of the first stream of the urine (FVU), taken at least 2 h after the last urination, were collected for LCR analysis. Discrepant results were further analyzed by direct fluorescence and a LCR with alternative primers.
Results: In men the prevalence of C. trachomatis infection by urethral culture was 13.45% and, after resolution of discordant results, the LCR method performed on FVU showed a sensitivity, specificity, positive predictive value and negative predictive value of 89.4%, 100%, 100% and 98.2%, respectively; the sensitivity of tissue cell culture was 92.8%. In female sex partners, the prevalence of C. trachomatis infection by cervical culture was 3.04%; LCR detected eight true positive samples, two more than tissue cell culture, and no false-negative results.
Conclusion: LCR analysis of FVU is a rapid, non-invasive technique and represents a good alternative to tissue cell culture. Further study is needed to investigate possible LCR inhibitors present in urine samples.     

Chlamydia trachomatis in subfertile women undergoing uterine instrumentation: an alternative to direct microbial testing or prophylactic antibiotic treatment

Chlamydia trachomatis is the major cause of tubal occlusion, and is also associated with IVF failure and spontaneous abortion. These infections are asymptomatic in most individuals and can persist in the genital tract for long periods of time in a form resistant to immune destruction. A significant percentage of couples seeking treatment for infertility might, therefore, harbour C. trachomatis in their genital tract. An unresolved question is what to do about this possible chlamydial persistence. Cervical, endometrial and semen samples can be tested for C. trachomatis and only positive individuals treated. Alternatively, all couples undergoing infertility treatment can receive prophylactic antibiotics. We advocate a third option, to screen and treat only individuals who are positive for systemic and/or local anti-chlamydial antibody production. Detection of species-specific C. trachomatis antibodies in peripheral blood will determine which individuals have been exposed to this organism and who, therefore, may be at risk for harbouring persistent forms. Identification of IgA antibodies in genital tract secretions may be an even better indicator of the presence of C. trachomatis in the genital tract. Circulating antibodies to the chlamydial 60kDa heat shock protein (hsp60) is a specific indicator of tubal occlusion and, furthermore, correlates with the continued presence of this micro-organism in the genital tract of non-human primates. Screening for both cervical IgA antibodies to C. trachomatis and serum IgG anti-chlamydial hsp60 appears to provide the best indication as to which women may be harbouring C. trachomatis.     

Antibodies to Chlamydia trachomatis heat shock proteins in women with tubal factor infertility are associated with prior infection by C. trachomatis but not by C. pneumoniae.

The antibody response to heat shock proteins 60 and 10 were studied in 163 patients with tubal factor infertility and in 163 age-matched pregnant women. The associations of these antibodies with specific antibodies to Chlamydia trachomatis and to Chlamydia pneumoniae as well as with antibodies to the common chlamydial lipopolysaccharide antigen were studied. Patients with tubal factor infertility had significantly higher frequencies and titres of all antibodies except to C. pneumoniae. In a logistic regression model an association was found between the prevalence of antibodies to the heat shock proteins and to C. trachomatis but no independent influence of antibodies to C. pneumoniae. No interaction between C. trachomatis and C. pneumoniae suggesting a synergistic effect was found although the heat shock proteins from these two organisms are immunologically similar. Antibodies to the chlamydial lipopolysaccharide also seemed to be related to C. trachomatis and not to C. pneumoniae in these women.     

The hypo-osmotic swelling test and the sperm mucus penetration test in determining fertilization of the human oocyte

The usefulness of the hypo-osmotic swelling (HOS) test and thesperm mucus penetration (SMP) test as sperm function tests forin-vitro fertilization was analysed in 56 couples. Using logisticregression analysis only the SMP test was independently relatedto fertilization (P = 0.004), no false negative results wereobtained, i.e. no fertilization if sperm from the ejaculatefailed to penetrate mucus. The HOS test was of no predictivevalue. The results justify a further examination of the SMPtest in other IVF centres.     

100例不育症患者解脲支原体和沙眼衣原体定量分析

目的为了分析不育症和非淋茵性尿道炎患者感染解脲支原体和沙眼衣原体定量检测结果的差异.方法荧光定量多聚酶链式反应(FQ-PCR)技术连续对100例(有97例作了UU检测,84例作了CT检测)本院生殖中心不育症患者及同时时662例(有470例作了UU检测,540例作了CT检测)普通性病和妇科门诊非淋患者CTDNA和UUDNA进行了定量检测.结果不育组UU阳性率=57/97(58.76%),UU拷贝对数值6.016±1.044;CT阳性率=7/84(8.33%),CT拷贝对数值4.968±2.190.普通非淋组UU阳性率=209/470(46.60%),UU拷贝对数值6.131±1.385;CT阳性率=62/540(11.48%),CT拷贝对数值5.894±1.943.结论UU是引起非淋和不育症的主要病原体.UU相对于CT对人类生育的危害更为严重.不育组和普通非淋组UU的定量结果没有统计学差异,而普通非淋组的CT的拷贝数则高于不育组,P＜0.05.     

Demonstration of Chlamydia trachomatis IgG antibodies in the male partner of the infertile couple is correlated with a reduced likelihood of achieving pregnancy

BACKGROUND: The objective of this study was to determine the prevalence of Chlamydia trachomatis among both men and women seeking help at an infertility clinic, and to prospectively follow the effect of previous infection on pregnancy rates and pregnancy outcome after a long follow-up period (mean 37 months). METHODS: A total of 244 infertile couples was tested for C. trachomatis IgG antibodies, and IgG(+) couples were also tested for C. trachomatis DNA by PCR in a first-void urine sample. Study parameters were serology, PCR results, clinical diagnoses, treatments, pregnancy rates and pregnancy outcome. As controls, age-matched and spontaneously pregnant women were also tested with serology. RESULTS: The prevalence of IgG antibodies was 24.2, 20.1 and 15.6% among infertile women, infertile men and control women respectively. The prevalence of C. trachomatis DNA was 6.8 and 7.1% among tested women and men respectively. The presence of C. trachomatis IgG antibodies in women was related to tubal factor infertility (TFI) (P = 0.002). Decreased pregnancy rates were seen in couples where the man was IgG(+) (P = 0.005) with no relationship to TFI. Among women who achieved pregnancy, there was no difference in pregnancy outcome between IgG(+) or negative couples. CONCLUSIONS: C. trachomatis IgG antibodies in the man of the infertile couple was related to decreased pregnancy rates and to the presence of IgG antibodies in the woman. There was a high prevalence of asymptomatic persistent infections among infertile couples.