Detection of IgG, IgM and IgA antibodies in patients with uncomplicated Chlamydia trachomatis infection: a comparison between enzyme linked immunofluorescent assay and isolation in cell culture.

The diagnostic value of serum IgG, IgM and IgA in patients with uncomplicated urogenital Chlamydia trachomatis infection was compared with isolation in cell culture. C. trachomatis specific antibodies were determined with an enzyme linked immunofluorescent assay using elementary bodies from C. trachomatis serotypes E,F,H,I,J and LGV2 as antigens. At least two sera from each patient were tested and cultures were also established on the same day. Excluding the IgM titres in men, significantly more IgG, IgA and IgM and combinations of these antibodies were observed in culture positive patients. The sensitivity with which IgG titres in men or IgG and/or IgM titres in men and women could be determined, was significantly lower using C. trachomatis LGV2 as the only antigen than when all 6 antigens were used. The presence of 10 or more leucocytes in the urine sediment of men correlated positively with an IgG or an IgG and/or IgM titre.

Factors influencing the infectivity of Chlamydia pneumoniae elementary bodies on HL cells.

The influence of variations in the pH, NaCl concentration, temperature, and concentrations of calcium and magnesium ions on the survival of Chlamydia pneumoniae elementary bodies (EBs) outside the host cells was investigated. The survival was determined after various incubation periods by counting the inclusion-forming units after C. pneumoniae was cultured for 72 h on monolayers of HL cells. The normal physiological conditions were restored prior to infecting the HL cells with C. pneumoniae. Declines in the infectivities of C. pneumoniae EBs were observed at pH values of lower than 5 and higher than 8 or at NaCl concentrations of less than 80 mM. The viability of C. pneumoniae EBs in SPG medium decreased as the temperature and/or incubation period increased. Incubation temperatures of up to 20 degrees C and incubation periods of up to 48 h did not affect the viability of C. pneumoniae. One hundred percent of the C. pneumoniae EBs were infective after 1 h of incubation at 35 degrees C, whereas 90, 50, and 40% survived after incubations of 8, 24, and 48 h, respectively. The viability of C. pneumoniae was unaffected within the investigated range of Ca2+ and Mg2+ ion concentrations in the medium. The presence of 10% fetal calf serum in the incubation medium had a stabilizing effect on the viability of C. pneumoniae. This effect became more pronounced as the incubation period increased.

Sexually communicable micro-organisms in human semen samples to be used for artificial insemination by donor.

Two hundred and thirty seven semen samples from 10 institutes for artificial insemination by donor (AID) in Belgium and the Netherlands were tested for the presence of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma urealyticum, herpes simplex virus, and cytomegalovirus. The incidence of these micro-organisms in the semen samples was 0%, 6.3%, 4.6%, 35.9%, 0%, and 0.4% respectively, and 47% of all samples were infected with one or more of the micro-organisms. As the ejaculates from which the samples had been taken had already been, or would be, used for AID, the exclusion of microbiological contamination with sexually communicable micro-organisms before insemination is indicated.

Evaluation of an enzyme immunoassay for the diagnosis of chlamydial infections in urogenital specimens.

A total of 194 male urethral and 402 cervical specimens were obtained from patients at the venereal disease outpatient clinic of University Hospital, Rotterdam, The Netherlands, to evaluate the IDEIA test (Boots Celltech) for the detection of chlamydial infections. The prevalences of culture-positive males and females were 17.5 and 8.2%, respectively. The respective overall sensitivities and specificities found were 67.6 and 93.7% for the males and 63.6 and 93.8% for the females. The highest sensitivity (83.3%) was found in male patients with more than 20 leukocytes per field in the sediment of the first-voided urine (magnification, X250) and in women with more than 10 leukocytes per field in a cervical Gram stain (magnification, X800). However, in men without urethritis and in women with fewer than 10 leukocytes per field in the Gram stain, sensitivities of 44.4 and 40%, respectively, were found. Culture-positive, IDEIA-negative results were predominantly observed in samples with few inclusions in the culture.

Evaluation of the direct fluorescent antibody test for diagnosis of chlamydial infections.

The direct fluorescent antibody test and two culture methods were compared for accurate diagnosis of chlamydial infections. Using the same samples, 109 were found to be positive in the microtitre method with the direct confirmation test without subpassage, whereas 66 were positive in the vial method with Giemsa staining and subpassage. The direct test was evaluated for accuracy using cervical and male urethral specimens. Specimens for culture were obtained prior to sampling for the direct test. For cervical samples the sensitivity of the direct test, with the vial method taken as reference, appeared to be 72.2% with a specificity of 93.5%. With the microtitre method as standard, these values were 55.9% and 91.3%, respectively for females, and for male patients 49% and 95.6%, respectively. For cervical samples, in which sampling for the direct test was carried out prior to sampling for culture, the values were 46.3% and 93.2% respectively. Both culture method and study population influenced the sensitivity of the direct test. According to our findings, the direct test cannot replace the culture method for diagnosis of chlamydial infections.

Prevalence of antibodies to Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma hominis in infertile women.

A total of 57 infertile women, who had been referred for in vitro fertilisation or for diagnostic laparoscopy, were tested for the presence of antibodies to Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma hominis. Four were excluded from the study. Of the remaining 53, 33 had laparoscopically obvious tubal disorders, such as adhesions, distal occlusions and strictures, and 20 did not. Antibodies to C trachomatis were found in 7/33 (21.2%) v 0/20, antibodies to N gonorrhoeae in 20/38 (60.6%) v 5/20 (25%), and antibodies to M hominis in 18/24 (75%) women with tubal disorders v 13/19 (68.4%) of those with no disorder. Antibodies to C trachomatis and N gonorrhoeae were significantly (p less than 0.05) more common in women with tubal disorders. The high prevalence of antibodies to N gonorrhoeae in infertile women without tubal disorders suggests that ciliated tubal epithelium is damaged after inflammation without this being laparoscopically visible. Our results confirm the important role of N gonorrhoeae and C trachomatis in the aetiology of infertility after tubal inflammation.

Survival of Chlamydia trachomatis in different transport media and at different temperatures: diagnostic implications.

We compared the survival of a laboratory strain of Chlamydia trachomatis serovar L-2 in different media and at different temperatures (room temperature, 4 degrees C, and -70 degrees C). At these temperatures the best storage medium was 2SP (0.2 mol/l sucrose in 0.02 mol/l phosphate buffer supplemented with 10% fetal calf serum). We used material obtained from patients to study the sensitivity of the culture method as a function of sample storage time and temperature. Compared with results on direct inoculation, material stored in 2SP for 48 hours gave 11% fewer positive cultures at 4 degrees C and 14% fewer at room temperature. Of samples which gave negative results on direct inoculation, 4% were positive after storage at 4 degrees C for 48 hours and 2% after storage at -70 degrees C for a week. As expected, the number of inclusion forming units in the original material proved to be important for the percentage of positive cultures among the stored samples.