Asymptomatic Chlamydia Trachomatis Research Articles

Cost-Effectiveness of Partner Pharmacotherapy in Screening Women for Asymptomatic Infection with Chlamydia Trachomatis

Objective To assess the cost-effectiveness of pharmacotherapy for male partners in screening women for asymptomatic infection with Chlamydia trachomatis (CT). Methods and Data A pharmacoeconomic decision analysis model was constructed for the health outcomes of a CT screening program, such as averted cases of pelvic inflammatory disease and infertility (major outcomes). Reinfection in the absence of partner pharmacotherapy was included in the model. Cost-effectiveness from a societal perspective was estimated for prevalence data from a selective opportunistic screening program in Amsterdam. For diagnosis of asymptomatic CT infection a Ligase Chain Reaction (LCR) test on urine was used; for pharmacotherapy of women and partners azithromycin was used. By linking health outcomes with health care costs and productivity losses, averted costs were estimated. Cost-effectiveness was expressed as net costs per major outcome averted. Results Partner pharmacotherapy reduces net costs per major outcome averted of the screening program by approximately 50%. Sensitivity analysis indicates significant improvements in cost-effectiveness of the screening program, even when relevant assumptions are varied. Within the broader framework of the screening program, partner pharmacotherapy is a cost-saving activity. Conclusions Inclusion of partner pharmacotherapy provides significant improvements in overall cost-effectiveness of the CT screening program among women aged 15 to 29. Partner pharmacotherapy lowers net costs per major outcome averted to the realm where implementation of the screening program should be considered. Considering the cost-saving potential, male partner pharmacotherapy should be pursued within the broader framework of a CT screening program for women. Reinfection should be included in any future pharmacoeconomic model of CT screening. Further work on this type of model should also be directed to linking cost-effectiveness to epidemiological models for the long-term spread of infectious diseases in populations.

Low diagnostic accuracy of selective screening criteria for asymptomatic Chlamydia trachomatis infections in the general population

Objectives: To develop and validate selective screening criteria for asymptomatic Chlamydia trachomatis infections in the general population. Methods: 11 505 people, aged 15–40 years, registered in 16 general practices in...

An assessment of diagnostic tests for the detection of asymptomatic Chlamydia trachomatis—A systematic review

An assessment of diagnostic tests for the detection of asymptomatic Chlamydia trachomatis—A systematic review

A prospective study of asymptomatic Chlamydia trachomatis in Barbadian women

A prospective study to determine the prevalence of asymptomatic female genital tract Chlamydia trachomatis infection was performed on 167 women at the Queen Elizabeth Hospital, Barbados, West Indies and at a private clinic. The ELISA (Microtrak, chlamydia EIA, Syva, CA) method was used to detect Chlamydia trachomatis antigen. Nineteen (11.4% 95% CI 6.5-16.3) women were found positive. The efficacy of a single 1 gram dose of azithromycin given orally to 18 patients was tested after 4 weeks. One patient who was pregnant was given 500 mg erythromycin four times daily orally for 1 week. Only six patients (including the pregnant patient) reported for follow up. All six repeat swabs were negative for C. trachomatis antigen. The prevalence of 11.4% asymptomatic chlamydial infection in endocervical swabs in Barbadian women is in agreement with a previous study which reported a prevalence of 18.4% +/7.8%. Patient compliance was assured, using a single dose of azithromycin. It was found to be as effective as doxycyline and ciprofloxacin as reported by other workers.

Immunity to heat shock proteins and pregnancy outcome

Heat shock proteins are among the first proteins produced by the zygote after fertilization. In addition, the maternal decidua also expresses heat shock proteins during the early stages of pregnancy. Autoimmunity to heat shock proteins is not typically evident in healthy women of reproductive age. However, a chronic microbial infection, such as an asymptomatic Chlamydia trachomatis upper genital tract infection, results in prolonged exposure of the immune system to the microbial 60 kDa heat shock protein (hsp60). This may result in immunity to conserved hsp60 epitopes and subsequent autoimmunity to self hsp60. Women undergoing in vitro fertilization (IVF) who never realized they had a chlamydial infection but who were positive for cervical anti-chlamydial immunoglobulin A (IgA) antibodies had a much lower pregnancy rate than did women who were negative for these antibodies. Furthermore, cervical IgA antibodies to the chlamydial hsp60, as well as to a synthetic peptide corresponding to an hsp60 epitope present in both the chlamydial and human hsp60, also correlated with IVF failure. In vitro incubation of newly fertilized human embryos in medium containing maternal serum was shown to be deleterious to embryo development if the sera was positive for antibodies reactive with human hsp60. In another study, the ability of human hsp60 to elicit a lymphocyte proliferative response (cell-mediated immunity) correlated with a history of spontaneous early stage pregnancy loss. Thus, autoimmunity to hsp60 might increase susceptibility to early stage pregnancy loss. Infect. Dis. Obstet. Gynecol. 7:35–38, 1999. © 1999 Wiley-Liss, Inc.

Immunity to heat shock proteins and pregnancy outcome.

Heat shock proteins are among the first proteins produced by the zygote after fertilization. In addition, the maternal decidua also expresses heat shock proteins during the early stages of pregnancy. Autoimmunity to heat shock proteins is not typically evident in healthy women of reproductive age. However, a chronic microbial infection, such as an asymptomatic Chlamydia trachomatis upper genital tract infection, results in prolonged exposure of the immune system to the microbial 60 kDa heat shock protein (hsp60). This may result in immunity to conserved hsp60 epitopes and subsequent autoimmunity to self hsp60. Women undergoing in vitro fertilization (IVF) who never realized they had a chlamydial infection but who were positive for cervical antichlamydial immunoglobulin A (IgA) antibodies had a much lower pregnancy rate than did women who were negative for these antibodies. Furthermore, cervical IgA antibodies to the chlamydial hsp60, as well as to a synthetic peptide corresponding to an hsp60 epitope present in both the chlamydial and human hsp60, also correlated with IVF failure. In vitro incubation of newly fertilized human embryos in medium containing maternal serum was shown to be deleterious to embryo development if the sera was positive for antibodies reactive with human hsp60. In another study, the ability of human hsp60 to elicit a lymphocyte proliferative response (cell-mediated immunity) correlated with a history of spontaneous early stage pregnancy loss. Thus, autoimmunity to hsp60 might increase susceptibility to early stage pregnancy loss.

Immunity to heat shock proteins and pregnancy outcome

Heat shock proteins are among the first proteins produced by the zygote after fertilization. In addition, the maternal decidua also expresses heat shock proteins during the early stages of pregnancy. Autoimmunity to heat shock proteins is not typically evident in healthy women of reproductive age. However, a chronic microbial infection, such as an asymptomatic Chlamydia trachomatis upper genital tract infection, results in prolonged exposure of the immune system to the microbial 60 kDa heat shock protein (hsp60). This may result in immunity to conserved hsp60 epitopes and subsequent autoimmunity to self hsp60. Women undergoing in vitro fertilization (IVF) who never realized they had a chlamydial infection but who were positive for cervical anti-chlamydial immunoglobulin A (IgA) antibodies had a much lower pregnancy rate than did women who were negative for these antibodies. Furthermore, cervical IgA antibodies to the chlamydial hsp60, as well as to a synthetic peptide corresponding to an hsp60 epitope present in both the chlamydial and human hsp60, also correlated with IVF failure. In vitro incubation of newly fertilized human embryos in medium containing maternal serum was shown to be deleterious to embryo development if the sera was positive for antibodies reactive with human hsp60. In another study, the ability of human hsp60 to elicit a lymphocyte proliferative response (cell-mediated immunity) correlated with a history of spontaneous early stage pregnancy loss. Thus, autoimmunity to hsp60 might increase susceptibility to early stage pregnancy loss. Infect. Dis. Obstet. Gynecol. 7:35–38, 1999. © 1999 Wiley-Liss, Inc.

Chlamydia trachomatisInfections in Female Military Recruits

Asymptomatic genital Chlamydia trachomatis infections in women can lead to pelvic inflammatory disease, infertility, and ectopic pregnancy. To design a chlamydia-control program, we conducted a large survey of women in the U.S. military. From January 1996 through December 1997, urine samples from 13,204 new female U.S. Army recruits from 50 states were screened by ligase chain reaction for C. trachomatis infection. Information on potential risk factors was obtained by questionnaire. With multivariate analysis, we identified criteria for a screening program. The overall prevalence of chlamydial infection was 9.2 percent, with a peak of 12.2 percent among the 17-year-old recruits. The prevalence was 15 percent or more among the recruits from five southern states. The following risk factors were independently associated with chlamydial infection: having ever had vaginal sex (odds ratio for infection, 5.9), being 25 years of age or less (odds ratio, 3.0), being black (odds ratio, 3.4), having had more than one sex partner in the previous 90 days (odds ratio, 1.4), having had a new partner in the previous 90 days (odds ratio, 1.3), having had a partner in the previous 90 days who did not always use condoms (odds ratio, 1.4), and having ever had a sexually transmitted disease (odds ratio, 1.2). A screening program for subjects 25 years of age or less (87.9 percent of our sample) would have identified 95.3 percent of the infected women. Among female military recruits, the prevalence of chlamydial infection is high. A control program that screens female recruits who are 25 years old or younger with urine DNA-amplification assays has the potential to reduce infection, transmission, and the sequelae of chlamydial infection.

Mailed home obtained urine specimens are suitable for the detection of asymptomatic Chlamydia trachomatis (CT) infections: A new screening approach

Mailed home obtained urine specimens are suitable for the detection of asymptomatic Chlamydia trachomatis (CT) infections: A new screening approach

Prevalence and serovar distribution of asymptomatic cervical Chlamydia trachomatis infections as determined by highly sensitive PCR

The prevalence rates and serovar distributions of Chlamydia trachomatis cervical infections were investigated in two different groups of women. Group I consisted of 393 asymptomatic young women (aged 17 to 30 years) who were invited to participate in a C. trachomatis screening program. Group II consisted of 734 randomly selected patients (aged 17 to 68 years) attending an inner-city gynecological outpatient clinic. C. trachomatis was detected in cervical scrapes by PCR specific for endogenous plasmid. These plasmid PCR-positive samples were subsequently subjected to genotyping by C. trachomatis-specific omp1 PCR-based restriction fragment length polymorphism analysis (J. Lan, J. M. M. Walboomers, R. Roosendaal, G. J. van Doornum, D. M. MacLaren, C. J. L. M. Meijer, and A. J. C. van den Brule, J. Clin. Microbiol. 31:1060-1065, 1993). The overall prevalence rates of C. trachomatis found in patients younger than 30 years were 9.2 and 11.8% in groups I and II, respectively. A clear age dependency was seen in group II, with the highest prevalence rate (20%) found in patients younger than 20 years, while the rate declined significantly after 30 years of age (5.9%). In women younger than 30 years, the genotyping results showed that serovars E, I, and D (in decreasing order) were frequent in group I, while serovars F, E, and G (in decreasing order) were predominantly found in group II. The study shows that C. trachomatis infections are highly prevalent in asymptomatic young women. The different serovar distributions found most likely reflect the different compositions of the study groups, but additional analysis of the case histories of individual patients suggests that certain serovars might be associated with symptomatic (i.e., serovar G) or asymptomatic (i.e., serovars D and I) infections.

Autoimmunity to spermatozoa, asymptomatic Chlamydia trachomatis genital tract infection and gamma delta T lymphocytes in seminal fluid from the male partners of couples with unexplained infertility.

The relationship between an undetected, asymptomatic Chlamydia trachomatis genital tract infection, the concentration of gamma delta and alpha b T cells in semen and sperm autoimmunity was examined in 48 male partners of couples with unexplained infertility. Immunoglobulin A (IgA) antibodies to C. trachomatis were detected in seminal fluids from 14 (29.2%) of the men. Only four of these were positive for circulating anti-chlamydial IgA, suggesting that the stimulus for antibody production was within the genital tract. In contrast, four men were positive for anti-chlamydial IgG in their semen; all were also seropositive for anti-chlamydial IgG. T lymphocytes bearing the alpha beta and gamma delta antigen receptors were present in every semen sample. Men with seminal anti-chlamydial IgA, however, had significantly (P = 0.035) elevated semen gamma delta T cell concentrations (median 3100 cells/ml) than did men lacking this antibody (median 1400 cells/ml); concentrations of alpha beta T cells were comparable in both groups. Genital tract sperm autoimmunity, as shown by antibodies bound to motile ejaculated spermatozoa, was detected in 13 (27.1%) men. The presence of these antibodies was associated with elevated concentrations of both gamma delta (median 4200 versus 700 cells/ml) and alpha beta (median 5000 versus 850 cells/ml) T cells (P = 0.0002 and 0.0001 respectively). Men with antisperm antibodies only in their serum had seminal T cell concentrations comparable with men testing negative for antisperm antibodies. Anti-chlamydial IgA was identified in semen from four of 10 men with IgA bound to their spermatozoa and in none of the men with only spermatozoa-bound IgG.(ABSTRACT TRUNCATED AT 250 WORDS)

Asymptomatic genitourinary Chlamydia trachomatis infection in women seropositive for human immunodeficiency virus infection: Spinillo A.; Gorini G.; Regazzetti A.; De Seta F.; Nicola S.; Zara C. ITA Obstet Gynecol 1994 83/6 (1005–1010)

International Journal of Gynecology & ObstetricsVolume 48, Issue 2 p. 253-254 Citations from the literature infectious disease Asymptomatic genitourinary Chlamydia trachomatis infection in women seropositive for human immunodeficiency virus infection Spinillo A.; Gorini G.; Regazzetti A.; De Seta F.; Nicola S.; Zara C. ITA Obstet Gynecol 1994 83/6 (1005–1010) First published: February 1995 https://doi.org/10.1016/0020-7292(95)90225-2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume48, Issue2February 1995Pages 253-254 RelatedInformation

Asymptomatic genitourinary Chlamydia trachomatis infection in women seropositive for human immunodeficiency virus infection.

To evaluate the prevalence of asymptomatic Chlamydia trachomatis genitourinary infection in women with human immunodeficiency virus (HIV) infection. The prevalence of asymptomatic chlamydial genitourinary infection in HIV-seropositive women was compared with both HIV-seronegative controls and women with unknown HIV status. Chlamydia trachomatis was isolated in cell culture from endocervical and urethral specimens. The prevalence of genitourinary C trachomatis infection among HIV-seropositive women was 18.3% (21 of 115), a rate significantly higher than in both HIV-negative women (11 of 136; P = .016) and controls with unknown HIV status (18 of 326; P = .0001). Crude odds ratios for endocervical and urethral chlamydial infection in HIV-seropositive women compared to HIV-seronegative controls were 2.6 (95% confidence interval [CI] 1.13-6.08) and 3.3 (95% CI 1.15-9.67), respectively. After adjustment for variables related to sexual habits, there was no difference in the risk of cervical C trachomatis infection between HIV-seropositive cases and HIV-seronegative controls (Mantel-Haenszel odds ratio 1.04, 95% CI 0.93-1.14; P = .41). Finally, in HIV-seropositive patients, both the severity of immunosuppression evaluated by CD4+, CD8+, and total lymphocyte counts and the detection of p24 HIV-related antigen did not correlate with the presence of chlamydial infection. Women infected with HIV are at high risk for asymptomatic genitourinary chlamydial colonization. To prevent a possible "epidemic" of pelvic inflammatory disease, appropriate screening programs and therapeutic strategies should be planned.

Prevalence of isolated urethral asymptomatic Chlamydia trachomatis infection in the absence of cervical infection in incarcerated adolescent girls.

Adolescent girls may have isolated asymptomatic urethral Chlamydia trachomatis infection. To determine if a single direct fluorescent antibody (DFA) slide can detect as many urethral and cervical infections as the use of separate slides and to determine if isolated urethral infection occurs. During pelvic examinations upon admission, DFA slides were prepared from the cervix, from the urethra, and with cells from both sites. Of 125 girls, 17 had C. trachomatis infection: 4 in the urethra only (24%), 5 in the cervical sample only (31%), 5 in both sites (31%), 3 had positive results only on the combined slide, and 1 had a positive result on the cervical slide and an inadequate urethral slide. Isolated urethral C. trachomatis infection occurs frequently, and sampling both sites as opposed to sampling the cervix alone increases the number of cases found by 24% (P < 0.002). Using a single slide to detect infection in both sites detects as many infections as using two separate slides.

Detection of Chlamydia trachomatis in semen by the polymerase chain reaction in male members of infertile couples

Our objective was to evaluate the presence of asymptomatic Chlamydia trachomatis infection by means of the polymerase chain reaction in male members of couples with previously undiagnosed infertility. Twenty-eight infertile-couples who had negative cultures or negative results when tested by deoxyribonucleic acid probe for Chlamydia trachomatis in semen and cervical samples were studied. Semen samples were tested for Chlamydia trachomatis by means of the polymerase chain reaction. Sera from both partners were diluted 1:128 and tested for immunoglobulin M antibodies to Chlamydia. Sera and ejaculated sperm were evaluated for the presence of antisperm antibodies. Semen analyses were also performed. Chlamydia trachomatis was identified in semen from 11 (39.3%) of the male partners. Its detection correlated with the presence in the ejaculate of motile sperm containing antisperm antibodies (p < 0.01). Either antisperm immunoglobulin G, immunoglobulin A, or both were located on sperm only from 5 (45.5%) of the 11 men whose results were positive when tested for Chlamydia trachomatis. Similarly, immunoglobulin G or immunoglobulin A antibodies to sperm were only detected in 5 (45.5%) of the spouses of men with Chlamydia in semen. Immunoglobulin M antibody to Chlamydia trachomatis was identified in only one of the men. However, antichlamydial immunoglobulin M antibodies were present in sera from 6 (54.5%) female partners of men with seminal Chlamydia trachomatis but in none of the other 17 women (p < 0.01). Although undetected by culture of deoxyribonucleic acid probe of semen samples, Chlamydia trachomatis was nevertheless identified in semen of some symptom-free men by the polymerase chain reaction. This is probably a result of the increased sensitivity of the polymerase chain reaction to detect Chlamydia trachomatis. The increased prevalence of an autoimmune response to sperm in men with this organism in their semen suggests that a subclinical chlamydial infection may activate an immune response to sperm. A similar association between Chlamydia trachomatis in semen and circulating antisperm antibodies in female partners indicates that Chlamydia may also induce an immune response to sperm in women. Infertility in these couples may be the result of a direct inflammatory response in the cervix or endometrium to repeated Chlamydia exposure or of the ability of Chlamydia to evoke an immune response to spermatozoa.

Screening for asymptomatic Chlamydia trachomatis infection in adolescent men by examination of voided urine.

Screening for asymptomatic Chlamydia trachomatis infection in adolescent men by examination of voided urine.

Laparoscopically verified acute salpingitis: Clinical diagnosis, laparoscopic grading, microbiological aetiology and second-look laparoscopy

First catch early morning urine (FCU) samples from a male population were compared with urethral swabbing to access the prevalence of symptomatic and asymptomatic Chlamydia trachomatis infection using an enzyme immunoassay (IDEIA). Syva “Microtrak” was used as the “gold” standard to detect C. trachomatis from smears prepared from all urine samples in this study. The sensitivity and specificity of the IDEIA assay compared to the “gold” standard was 97·7% and 98·6%, respectively. Of the 615 male patients screened for C. trachomatis 420 (68%) were asymptomatic and 179 (29%) patients were diagnosed as having non-gonococcal urethritis. A further 16 patients had minimal signs and symptoms. Overall C. trachomatis was detected in 103 (16·7%) male patients. Of the 195 patients presenting with symptoms 42% had C. trachomatis detected. Nine of the 103 positive patients failed to provide a FCU, therefore a valid comparison was made between FCU and urethra swabbing from 94 positive and 512 negative patients. Twenty-one of the 94 positive patients were asymptomatic and antigen was detected from 2021 in FCU compared with 721 from urethra swabs. In summary 9094 (95·7%) positive patients were diagnosed by examination of FCU compared with 5994 (62·7%) by examination of urethral swabs.FCU is an ideal sample for the detection of C. trachomatis in both symptomatic and asymptomatic male patients. This non-invasive technique is more acceptable to the patient and clinician and would allow the widespread screening of C. trachomatis from the male population.

A comparison of urine and urethral swabbing for the diagnosis of C. trachomatis infection in males

First catch early morning urine (FCU) samples from a male population were compared with urethral swabbing to access the prevalence of symptomatic and asymptomatic Chlamydia trachomatis infection using an enzyme immunoassay (IDEIA). Syva “Microtrak” was used as the “gold” standard to detect C. trachomatis from smears prepared from all urine samples in this study. The sensitivity and specificity of the IDEIA assay compared to the “gold” standard was 97·7% and 98·6%, respectively. Of the 615 male patients screened for C. trachomatis 420 (68%) were asymptomatic and 179 (29%) patients were diagnosed as having non-gonococcal urethritis. A further 16 patients had minimal signs and symptoms. Overall C. trachomatis was detected in 103 (16·7%) male patients. Of the 195 patients presenting with symptoms 42% had C. trachomatis detected. Nine of the 103 positive patients failed to provide a FCU, therefore a valid comparison was made between FCU and urethra swabbing from 94 positive and 512 negative patients. Twenty-one of the 94 positive patients were asymptomatic and antigen was detected from 20 21 in FCU compared with 7 21 from urethra swabs. In summary 90 94 (95·7%) positive patients were diagnosed by examination of FCU compared with 59 94 (62·7%) by examination of urethral swabs. FCU is an ideal sample for the detection of C. trachomatis in both symptomatic and asymptomatic male patients. This non-invasive technique is more acceptable to the patient and clinician and would allow the widespread screening of C. trachomatis from the male population.

Detection of asymptomatic Chlamydia trachomatis infection in adolescents

Endocervical swabs from 137 asymptomatic girls 12–18 years of age (mean 16.1 years) were tested for Chlamydia trachomatis using a direct fluorescent antibody (DFA) slide test (MicroTrak, Syva Co., Palo Alto, CA) and compared with the tissue culture isolation of the organism. The DFA slides were examined for quality of the specimen as well as for the presence of elementary bodies. Of 137 slides, 5 (3.6%) were “poor” (less than 50 epithelial cells per well) and were excluded from the analysis. The DFA test identified 26 (89.7%) of 29 culture-positive specimens and 102 (99.0%) of 103 culture-negative specimens. The DFA test is a valuable screening tool (positive predictive value 96.30%, negative predictive value 97.14%) for identification of asymptomatic chlamydial cervical infection in adolescents when slides are interpreted for adequacy of the specimen as well as the presence of elementary bodies.

Asymptomatic Chlamydia Trachomatis Infections Among Sexually Active Men

Genital infections with Chlamydia trachomatis have been recognized as a significant public health problem in the United States. Studies of normal pregnant women have suggested that a large reservoir of asymptomatic chlamydial infection is present in poor, inner-city populations [1,2]. Among normal pregnant women, young age, out-of-wedlock conception, and multiple sexual exposures have been recognized as risk factors for endocervical infections with C. trachomatis [1-3]. Young age has also been shown to be a risk factor for C. trachomatis infection in men attending a sexually transmitted disease clinic [4]. Considerably less is known about asymptomatic infections in men in settings other than sexually transmitted disease clinics. Because men may be more likely to transmit sexually transmitted pathogens to susceptible female partners than vice versa [5], men who are unaware that they are infected are likely to play a critical role in maintaining the high prevalence of chlamydial infections in certain populations.