Persistence of chlamydial antibodies after pelvic inflammatory disease

Serum antibodies to Chlamydia trachomatis in women with ectopic pregnancy, normal pregnancy or salpingitis

Serum antichlamydial antibodies were studied in three groups. Group A included 49 women with recent ectopic pregnancy, group B included 56 women with normal first trimester pregnancy, and group C included 20 women with a first episode of acute salpingitis. In the ectopic pregnancy group, a significantly higher percentage of women had IgG antichlamydial antibodies than in the normal pregnancy group (75.5% vs. 46.4%, P less than 0.001). Women with acute salpingitis had the same prevalence of IgG antibodies as patients who had an ectopic pregnancy (60% vs. 75.5%, P less than 0.10). In the ectopic pregnancy group, the women had a significantly higher geometric mean titer (GMT) of antichlamydial IgG antibodies than women with an intra-uterine pregnancy (70.4% vs. 27.3%, P less than 0.001). The results suggest that there is a positive relation between prior Chlamydia trachomatis infection and risk for tubal pregnancy.

Further details on sequelae at the cervical and tubal level of Chlamydia trachomatis infection in infertile women

OBJECTIVE

Relationships were studied between correlates of sexually transmitted diseases and chlamydial antibodies versus cervical mucus abnormalities and tubal abnormalities. An estimate was also attempted of the baseline prevalence of endogenous tubal abnormalities.

DESIGN

Prospective, descriptive.

SETTING

The outpatient department of the Fertility Unit of the Department of Obstetrics and Gynaecology of the Groningen University Hospital.

PATIENTS

Females (n = 184) of infertile couples consecutively visiting the department for evaluation and treatment.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Sexually transmitted disease correlates, cervical chlamydial infection, cervical and serum chlamydial antibodies, cervical mucus qualities according to World Health Organization criteria, tubal abnormalities.

RESULTS

Of the 175 cervical mucus samples studied, subnormal quality was because of imperfect timing of collection of 22 of the 23 subnormal samples. Tubal abnormalities correlated with more than five lifetime sexual partners (P less than 0.035), as well as with serum immunoglobulin G antibodies (P less than 0.05), which could be because of interaction between both risk factors.

CONCLUSIONS

No correlation was found between subnormal cervical mucus and chlamydial infection. Approximately two thirds of the tubal abnormalities seem unrelated to exogenous factors, although further study seems warranted.

Laboratory techniques for the diagnosis of chlamydial infections

Yolk-sac inoculation of embryonated eggs was superseded 25 years ago by the use of cell cultures (often McCoy) for the isolation of Chlamydia trachomatis. Centrifugation of specimens onto the cell monolayers was shown to increase sensitivity, but little of late has further improved sensitivity which is at least ten-fold greater than that of eggs. However, culture is slow and labour intensive so that non-cultural techniques without these drawbacks have come to dominate. Direct fluorescent antibody (DFA) tests are rapid and have sensitivities that range from 70% to 100% for men and 68% to 100% for women, and specificities that range from 87% to 99% for men and 82% to 100% for women; if the tests are read by competent observers the values are at the top end of the ranges. The detection rate may be enhanced even further by relatively low-speed centrifugation of specimens before staining. Skilled reading is not a feature of enzyme immunoassays (EIAs) which according to the literature have sensitivities that range from 62% to 97% for men and 64% to 100% for women, and specificities that range from 92% to 100% for men and 89% to 100% for women. However, comparison against poor reference tests is responsible for most of the higher values and the clinician should not be misled into believing that EIAs have excellent sensitivity; the lower values in the ranges are closer to reality. Furthermore, EIAs that are being designed for use by general practitioners should be regarded with the greatest caution since lack of sensitivity means that chlamydia-positive patients will go undetected. The polymerase chain reaction (PCR) is not bedevilled by insensitivity but it is no more sensitive than the most sensitive cell culture or DFA tests. PCR is unsuitable for routine diagnosis but has a place as a research tool. For men, examination of "first-catch" urine samples by the best of the non-cultural procedures provides an acceptable non-invasive approach to diagnosis; for women, the value of examining urine may be less, but needs to be thoroughly tested. However, there is little doubt that a Cytobrush used to obtain cervical specimens holds no practical advantage over a swab. Serological tests are reliant on the provision of paired sera for making a diagnosis; high antibody titres in single sera may be suggestive of an aetiological association in deep-seated chlamydial infections (epididymitis, arthritis, salpingitis, etc), but unequivocal interpretation is unusual, particularly in an individual case, since the distinction between a current and past infection is problematical.

Induction of antibody response to Chlamydia trachomatis in the genital tract by oral immunization

Groups of BALB/c mice were orally immunized with Chlamydia trachomatis serovar L2/434/Bu in order to characterize the nature and kinetics of the chlamydial antibody response in the cervix and other mucosal sites. These animals were subsequently challenged intravaginally to determine whether oral immunization offers protection against chlamydial antigen shedding in the genital tract. Following oral immunization, immunoglobulin A antibody activity was detected in the genital tract as well as other mucosal sites. Subsequent intravaginal challenges exhibited booster effects on preexisting antibody activity in the genital tract. Significant protection against challenge infection in the genital tract was observed by oral immunization. This was indicated by the absence of any chlamydial antigen shedding in cervical secretions. On the other hand, passively administered chlamydial-specific serum immunoglobulin G antibody did not significantly influence the course of cervical shedding of the organism and did not confer any protection against a subsequent intravaginal challenge. It is concluded that prior oral immunization can induce a secretory antibody response in the genital tract and provide protection against subsequent infection.

Immune response in chlamydial conjunctivitis among neonates and adults with special reference to tear IgA

Tear and serum samples from 128 neonates and 122 adults with conjunctivitis were examined for antibodies to Chlamydia trachomatis with a micro-immunofluorescence (MIF) technique and the results compared to antigen detection by culture, enzyme immunoassay (EIA) (Chlamydiazyme, Abbott) and direct immunofluorescence (IF) (MicroTrak, Syva and Chlamyset, Orion) tests. From the 52 culture-positive adults, chlamydial IgA (titre greater than or equal to 1:8) antibodies were detected in 81% of the tear and in 62% of the serum samples, while 88% had such serum IgG antibodies (titre greater than or equal to 1:32). The persistence of chlamydial IgA in tears and sera was related to the duration of symptoms of conjunctivitis and the antibody titres declined after institution of antibiotic treatment. In the adults, the sensitivity of the MIF tear IgA antibody test (81%) was higher than that of the EIA (71%) and the IF (MicroTrak 71% and Chlamyset 62%) tests. The specificity for the MIF test was 79%, while it was 100% for the EIA and the two IF tests. Of the 67 chlamydia-infected neonates, 36% had chlamydial tear IgA antibodies, while such antibodies were only found in 15% of the sera. No neonates with chlamydia-negative conjunctivitis had chlamydial IgA antibodies. The MIF test may be used as a diagnostic method complementary to culture, EIA and IF tests in the diagnosis of chlamydial conjunctivitis in adults, but is not applicable in neonates.

Chlamydial IgG and IgA in serum and follicular fluid among patients undergoing in vitro fertilisation

The point prevalence of IgG and IgA antibodies to Chlamydia was analyzed in serum and follicular fluid in 63 patients undergoing in vitro fertilisation (IVF) in comparison to sera of 298 healthy women by the single serovar (L2) inclusion immunoperoxidase assay (IPA). The presence of specific IgG and IgA to Chlamydia in follicular fluid was demonstrated. No statistical association was found between the presence of specific Chlamydia IgG and IgA in serum and follicular fluid to oocyte fertilization. The positive predictive value for mechanical infertility of Chlamydia IgG at titers of greater than or equal to 128 and IgA titers at greater than or equal to 16 was 91 and 92%, respectively, in this high-risk group for mechanical infertility. Multiple regression analysis singled out Chlamydia IgG levels as a major contributor to the variance between the groups of infertile patients.

Laboratory survey of Chlamydia trachomatis ocular infections

The authors used immunofluorescence and immunoperoxidase tests to study a group of 101 patients with acute or chronic conjunctivitis, etiologically unrelated to conventional bacterial pathogens, and a control group of 30 healthy adults. Positive titers of IgG in serum and of IgA in lacrimal secretions against Chlamydia, detected by IPA, correlated with the identification of microorganisms by direct immunofluorescence. The use of both tests allows a precise evaluation of the stage of the infection and of its evolutive pattern.

Antigen specific serum antibody response to Chlamydia trachomatis in patients with acute pelvic inflammatory disease

Sera from 35 patients with acute pelvic inflammatory disease (PID) with and without Chlamydia trachomatis confirmed by culture and sera from 19 control patients with neither evidence of pelvic infection nor C trachomatis infection were studied for the presence of serum IgG, IgA, and IgM antibodies to C trachomatis using enzyme immunoassay (EIA) and immunoblotting techniques. There was no correlation between the antibody concentrations in the EIA and the spread of chlamydial infection, as determined by cervical, endometrial, and laparoscopic sampling for chlamydia. The immunoblot analysis showed antibodies to the major outer membrane protein (MOMP) of C trachomatis elementary bodies in all patients who had had C trachomatis isolated. Reactivity was also frequently observed against the 68, 62, 60, 45, and 31 kilodalton antigens. About 20 antigenic polypeptides were identified. Differences in antibody prevalence to specific chlamydial antigens, however, were not related to the site of chlamydial isolation or serum antibody concentrations observed with the EIA. The results indicate that patients with PID with and without upper genital tract infection with C trachomatis cannot be differentiated by reactivity of sera to specific chlamydial polypeptide antigens. The determination of a specific serum IgA antibody response by EIA was the most effective single test to discriminate between patients with and without acute chlamydial infection.

Chlamydia trachomatis infection in primary unexplained infertility

In recent years Chlamydia trachomatis has emerged as a significant cause of acute salpingitis and reproductory failure. In this study, 85 women suffering from primary infertility and 85 parous women as control group were screened for C. trachomatis genital infection by means of cell culture and antigen detection on genital samples as well as the detection of anti-chlamydial antibodies in blood. C. trachomatis was detected in 31.8% of infertile women and 5.8% of fertile subjects. Isolation of C. trachomatis in cell culture proved to be the most reliable diagnostic tool when compared to immunofluorescence staining on smears and serology. Although the latter may be considered of great value in epidemiological researches, culture isolation should be associated for the diagnosis of active infection.

Seroepidemiology of chlamydia in Costa Rica

A population-based study of the sero-epidemiology of chlamydia was performed among a nationally representative sample of 760 Costa Rican women aged 25 to 59 years. Interviews and sera collection were completed between September 1984 and February 1985. The overall seroprevalence of chlamydial antibodies among these women was 56.1%. Women 25 to 39 years of age had a seroprevalence of 51.1%, while women 40 to 59 years of age had a seroprevalence of 64.2%. Women who reported no prior sexual activity had a seroprevalence rate of 48.6%, compared with a seroprevalence rate of 80.7% among women who reported three or more lifetime sexual partners. The geometric mean titre (GMT) of seropositive women ranged from 34.4 among the women who reported no prior sexual activity to 155.0 among the women with three or more lifetime sexual partners. Sero-positivity was more consistently associated with sexual activity than with age. Women with serological evidence of past Herpes simplex virus type 2 (HSV-2) or syphilis infection were more likely to be seropositive than were women without evidence of exposure to these sexually transmitted diseases, even when controlled for age and the number of lifetime sexual partners. The seropositivity among never sexually active women indicates the probable presence of Chlamydia pneumoniae infections, while the high seroprevalence of chlamydial antibodies among the sexually active women suggests that sexually transmitted Chlamydia trachomatis infections represent a public health problem not previously quantified in Costa Rica. Further seroepidemiological and/or culture studies are warranted to determine the incidence and prevalence of sexually transmitted chlamydial infection among men and younger women.

Significance of immunoglobulin A titres in the diagnosis of urogenital chlamydial infections

The significance of chlamydial serum IgA compared with IgM and IgG in the diagnosis of urogenital chlamydial infection was evaluated using 120 sera from different categories of patients. In urethritis patients both IgM and IgA antibodies were not found to be present consistently, whereas in patients with deep-seated chlamydial infection, IgA was more often present. Although of limited value in superficial infections, demonstration of IgA antibodies may be of value in the diagnosis of deep-seated chlamydial infections.

The significance of the ipazyme IgA and IgG antibody test in the diagnosis of urogenital chlamydial infections

Urogenital specimens from 200 male and female patients were cultivated for the detection of C. trachomatis. For comparison, serum of the same patients was investigated with the Ipazyme IgA and IgG test. This comparison of culture and serological tests revealed a sensitivity of the IgA Ipazyme test of 56% and a specificity of 81%. For the IgG Ipazyme test, the corresponding values were 77% and 39%. The sensitivity of the conventional immunofluorescence test reached 46% and its specificity was 50% for the same group of patients. Antibiotic treatment of 13 IgA-positive patients resulted in a significant decrease of the titre in only one case. The introduction of the Ipazyme test does not open a new aspect in chlamydial serology, i.e. the diagnostic value of serology for the detection of a current chlamydial infection remains low.

Prevalence of IgA and IgG antichlamydial antibodies in women in the third trimester of pregnancy

The prevalence of serum antichlamydial IgA and IgG antibodies was investigated by screening 77 randomly selected patients who were in the third trimester of pregnancy. An indirect immunoperoxidase assay that quantitates IgA and IgG was used for screening. Twenty-five women had both IgA and IgG antibodies; an additional ten women had only IgG antibodies. These findings suggest that greater than 45 percent of pregnant women tested had been exposed to Chlamydia trachomatis, and more than 32 percent had evidence of active infection.

Prevalence of antibody to Chlamydia trachomatis in spontaneous abortion and infertility

A higher prevalence of Chlamydia trachomatis antibody occurred in 57.6% of women with recurrent abortion, but not in their male partners, compared to 33.7% of normal pregnant women (p less than 0.01) and 44.2% of infertile women (NS). The mean titer for the recurrent abortion group was not significantly elevated, compared to controls. Women with blocked fallopian tubes had the highest prevalence of elevated titers (p less than 0.01) and the highest mean titer (p less than 0.001). Despite multiple testing, no women or men were chlamydia culture-positive. The lack of isolation among patients with antibody could be due to cryptic infection at a site not amenable to culture or to inhibition by secretory IgA. There could also be nonspecific stimulation of chlamydial antibody caused by other infections such as mycoplasma. The presence, though at a low level, of antibody in culture-negative patients suggests chlamydia may not be directly associated with recurrent abortion but reflect previous exposure to chlamydia or an altered immune system.