Serological studies on the role of Chlamydia in the aetiology of non-specific urethritis

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.

Evidence of Chlamydia trachomatis infection in sexually acquired reactive arthritis

Thirty male patients with sexually acquired reactive arthritis (SARA) have been studied at the time of their initial presentation and thereafter. Chlamydia trachomatis was isolated from the urethral exudate of 9 (36.0%) of the 25 patients from whom urethral specimens were taken, and elevated titres of IgM antibody of C. trachomatis were detected in 11 (36.6%) of the 30 initial sera. Thirteen (43.3%) of the patients has a positive urethral culture and/or elevated titre of IgM antibody, and it is therefore suggested that 43.3% of these patients suffered an acute chlamydial infection at or near the time of the onset of their joint disease. The demonstration of 4-fold or greater rises and/or falls in IgM antibody titre (8 patients) and IgG antibody titre (6 patients) in a group of 15 men studied throughout the course of their disease strongly supports this conclusion. A positive urethral culture and/or raised titre of IgM serum antibody was also detected in 25 (50%) of 50 men with uncomplicated nongonococcal urethritis (NGU), suggesting that the prevalence of chlamydial infections in the 2 conditions is similar. Titres of IgG serum antibody to C. trachomatis were, however, significantly higher in patients with SARA than in those with NGU or other rheumatic diseases, and in healthy controls. The geometric mean titres (GMT) of IgG serum antibody in patients with SARA, NGU, rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus, and in healthy controls were 1:47.5, 1:8.6, 1:2.2, 1;2.2, 1:3.5, and 1:1.4, respectively. These findings suggest that an exaggerated antibody response to acute infection by C. trachomatis may be an important factor in the development of SARA in some but not all patients.

The rôle of Chlamydia trachomatis in genital-tract and associated diseases

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Chlamydial infection in animals: a review

A review of the literature concerning chlamydial infection in birds and animals, particularly domestic animals is presented. Following a general discussion of the agent, the nature of chlamydial infection and diagnostic criteria, information regarding disease is summarized for each species. The possibility of zoonotic transmission is also discussed.

Etiology of nongonococcal urethritis. Evidence for Chlamydia trachomatis and Ureaplasma urealyticum

Chlamydia trachomatis, Ureaplasma urealyticum (T-mycoplasma), and Hemophilus vaginalis have previously been considered possible etiological agents in nongonococcal urethritis (NGU). In this study, current C. trachomatis infection was confirmed by culture and (or) micro-immunofluorescence serology in 26 of 69 men experiencing afirst episode of NGU, and 1 of 39 with no urethritis. Serum IgM immunofluorescent antibody to chlamydia was demonstrated in 16 of 20 men with chlamydia culture positive NGU, and 3 of 39 with chlamydia culture negative NG, and none of 34 with no urethritis. 9 of 10 culture positive men with less than or equal to 10 days symptoms developed immunofluorescent antibody seroconversion in paired sera. U. realyticum was isolated significantly more often and in significantly higher concentration from first voided urine from chlamydia-negative cases of NGU than from chlamydia-positive NGU. Ureaplasmacidal antibody titers increased fourfold in six men, four of whom had negative cultures for for unreaplasma. H. vaginalis was isolated from c9 of 33 men with no urethritis and 2 of 69 with NGU. C. trachomatis is susceptible, and U. urealyticum is resistant to sulfonamides. A 10-day course of sulfisoxazole therapy produced improvement in 13 of 13 chlamydia-positive, unreaplasma-negative, and only 14 of 29 chlamydia-negative, unreaplasma-positive NGU cases (P less than 0.002). Thus, culture, serology, and response to therapy support the etiologic role of chlamydia in NGU. Quantitative culture and response to therapy suggest U. unrealyticum may cause many cases of chlamydia-netative NGU.

Simplified serological test for antibodies to Chlamydia trachomatis

Three-hundred sixty sera from unselected patients attending two London venereal disease clinics were examined by a microimmunofluorescence test. Eleven egg-grown serotypes of Chlamydia trachomatis and the so-called "fast" strain SA2(f) were used as antigens. Of the 360 sera tested, 119 (33%) reacted to a titer of 1:16 or above with at least one antigen. Of these positive sera, over 50% cross-reacted with all 12 serotypes, and 95.5% reacted with SA2(f) in addition to other antigenic types. It is suggested that SA2(f) could be used as a single antigen for preliminary screening of a large number of sera for the presence or absence of chlamydial antibody.

Non-specific urethritis and the tetracyclines

The possible aetiological factors in non-gonococcal and non-specific urethritis are reviewed. The response of NSU to various courses of different tetracycline drugs is assessed. Prolonged courses of treatment did not give better results than shorter courses. When reviewing the infective aetiology of non-gonococcal urethritis, it was noted that more than one organism (or potential pathogen) would be present in many cases. It is therefore surmised that there may be at times a mixed aetiology and at other times a truly non-specific aetiology. Isolations by different workers have indicated that the following organisms might be expected: Chlamydia 40 per cent.; Mycoplasma-M. hominis 20 per cent., T-strain over 60 per cent.; Trichomonas 15 per cent.; Candida possibly over 5 per cent. Truly non-specific urethritis may account for 25 to 30 per cent. of cases.

Fluorescent antibody studies in chlamydial infections

Irradiated McCoy cells infected with genital strains of Chlamydia trachomatis were grown in wells on slides coated with polytetrafluoroethylene. The inclusions produced in this system formed the antigen in an indirect immunofluorescence test, which detected group-specific chlamydial antibodies in sera from patients attending veneral disease clinics. Chlamydial antibodies were found more frequently and in higher titer in sera from women attending veneral disease clinics then in sera from a less promiscuous population attending a Family Planning Association clinic. Paired sera from 13 patients with nongonococcal urethritis from whom chylamydiae had been isolated were tested against the homologous isolates; seroconversion was demonstrated in only one instance, and antibody was present in the first serum specimens of all the other patients. Chlamydia-specific immunoglobulin M was found in four of eight patients with psittacosis and in a proportion of sera from patients attending veneral disease and Family Planning Association clinics. The antigen for this immunofluorescence test can easily be prepared in laboratories with cell culture facilities for the isolation of C. trachomatis, and the test should be useful for laboratories which cannot undertake the micro-immunofluorescence test.