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Background: Upper genital tract chlamydial infections in women are on the increase, and serology might be a convenient tool for diagnosis. Evaluations of this approach are needed in women with or without microbiologic evidence of organisms in the upper genital tract. Goals: To compare the results of antibody assays with cervical culture and upper genital tract histopathology in women with pelvic pain and chlamydial plasmid DNA in endometrial biopsies. Study Design: Chlamydia trachomatis plasmid DNA was detected by polymerase chain reaction (PCR) on extracted deparaffinized endometrial biopsy tissue. Five antichlamydial antibody assays were performed measuring total antibodies or immunoglobulin G (IgG), IgM, and IgA classes on sera from 14 women with plasmid DNA as well as 31 without plasmid DNA. Results: Accepting the presence of plasmid DNA as the gold standard, no single test had total diagnostic accuracy. The best sensitivity and specificity occurred with the following assays: whole inclusion fluorescence (WIF) (100% and 80.6%); microimmunofluorescence IgM (MIF IgM) (78.6% and 93.6%); and heatshock protein-60 enzyme immunoassay (42.9% and 100%). Although recombinant anti-lipopolysaccharide enzyme-linked immunosorbent assays measured antichlamydial antibodies in a large proportion of these women, specificity was low. The sensitivity and specificity of cervical culture was 28.6% and 100% and of endometrial histopathology was 71.4% and 48.4%. Analysis of patient serological profiles suggested that 6 women without plasmid DNA may have been cases that were missed by PCR. Conclusions: Evaluations of assays to diagnosis Chlamydia trachomatis upper genital tract infections could use the presence of organisms or their markers in the upper genital tract as a standard of comparison. Some of these serological assays, such as WIF or MIF IgM, may be helpful in diagnosis, but more studies are needed., No single blood test appears to be able to accurately distinguish women with and without chlamydia infections who have characteristic pelvic pain. Blood tests were performed on 45 symptomatic women and compared with genetic tests on tissue samples. Fourteen of these women had confirmed chlamydia infections and 31 were not infected. The percentage of true positive blood test results ranged from 42.9% using the heatshock protein-60 enzyme immunoassay (HSP-60 EIA) to 100% using whole inclusion fluorescence (WIF). The percentage of true negative blood test results ranged from 80.6% using WIF to 100% using HSP-60 EIA.

Abstract Objectives: To estimate the prevalence of Chlamydia trachomatis in asymptomatic women attending general practice; to assess the potential of the ligase chain reaction as a screening tool; and to [...]

Background and Objectives: The Syva MicroTrak enzyme immunoassay (EIA) is used widely for screening women infected with Chlamydia trachomatis. Confirmatory tests used in conjunction with EIA screening have shown that false-positive results are common. Goals: To evaluate the specificity of the Syva MicroTrak EIA by confirmation of positive specimens with the Syva Direct Fluorescent Specimen Test. Study Design: Of 6,039 endocervical specimens collected from women attending Colorado family planning clinics, 328 positive EIA results (5.4%) were obtained by Syva MicroTrak EIA. A random subset of 136 positive specimens was tested by Syva Direct Specimen Test. Twenty of 136 specimens (14.7%) negative by Syva Direct Specimen testing were also tested by Syva blocking antibody tests (9 of 20 positive, 45%) and Roche Amplicor polymerase chain reaction (PCR; 6 of 20 positive, 30%). Of 20 specimens positive by Syva MicroTrak EIA and negative by Syva Direct Specimen Test, 11 (55%) were also negative by blocking antibody and PCR, including three specimens with initial EIA sample-to-cutoff ratios greater than 2. Conclusions: Confirmatory testing of Syva MicroTrak EIA positive specimens with Syva Direct Specimen Test showed that 14.7% were false positive. Coupling the Syva Direct Specimen test with either blocking antibody or PCR reduces the rate of false-positive results to 8%., A popular commercial screening test for Chlamydia appears to require follow-up testing on women testing positive to reduce the number of false-positive tests, but any one follow-up test may produce a false-negative result. Among 136 cervical secretion specimens originally testing positive for Chlamydia, 20, or 15%, tested negative on a second type of test. Of these 20, 11 tested negative on both of yet two other types of test while the rest tested positive on one or both of these other tests. Therefore, follow-up testing by two different tests reduced the false-positive rate from 15% to 8%.

Background and Objectives: The aim of the study was to investigate the value of the Gen-Probe PACE 2 assay for routine diagnosis of Chlamydia trachomatis in genital specimens of symptomatic and asymptomatic men and women patients. Study Design: Samples were collected from 90 men and 299 women patients and tested by using the Gen-Probe assay and the EIA MicroTrak. Discrepant results were further analyzed by immunofluorescence, a second run of the Gen-Probe assay, and a probe competition assay (PCA) to establish the number of true positive and negative outcomes based on the two tests used. Results: The overall prevalence of C. trachomatis was 8.5% in all patients tested (women: 3.7%, men: 13.3%) with an overall agreement of 95.4% between the two diagnostic methods. Of the 18 discordant results, 12 (67%) were considered to be false positive in the Gen-Probe assay and 3 (16%) false positive in the EIA. Two (11%) positive results were missed in the Gen-Probe assay and 1 (6%) in the EIA, all observed in female specimens. The sensitivities and specificities of the EIA were 91.7% and 100% for men and 100% and 99% for women, and for the Gen-Probe assay were 83.3% and 100% for men and 100% and 95.8% for women, respectively, when compared with true positive and true negative results. Although the predictive value for all positive results (PVP) was 88% for the EIA and 78.2% for the Gen-Probe assay, it was only 47.8% for positive female samples when using the Gen-Probe assay. Conclusion: The Gen-Probe assay revealed a sensitivity comparable with the EIA. The accuracy of test results provided by a single Gen-Probe assay was considerably lower than by MicroTrak reducing the utility of PACE 2 as a diagnostic technique for Chlamydia diagnosis. Due to the high rate of false-positive samples in the Gen-Probe assay, positive results with a low value of relative light units have to be further analyzed by confirmation procedures., Gen-Probe's PACE 2 test for Chlamydia trachomatis (C. trachomatis) infection appears to have a high false positive rate compared to the MicroTrak enzyme immunoassay (EIA). PACE 2 analyzes DNA sequences in order to diagnose infections with C. trachomatis. Chlamydial infections may be sexually transmitted. People infected with C. trachomatis may or may not have symptoms. Samples were collected from 90 men and 299 women. The samples were tested by PACE 2 and MicroTrak EIA. Agreement in results between the two tests occurred in 95.3% of the cases. When results differed between the two tests they were analyzed further. Fifteen of eighteen samples with differing results were from women. Twelve (67%) of these false-positive results occurred with PACE 2 and three (16%) occurred with MicroTrak. PACE 2 did not identify chlamydial infection in two male samples and MicroTrak did not identify one infection in a male sample. Because of the high false positive rate with PACE 2, borderline samples require further analysis.

Background and Objectives: Non-invasive tests are needed to detect Chlamydia trachomatis in the genital tract. For men, urine appears to be a useful specimen for chlamydial antigen or nucleic acid detection. Goal of this Study: To evaluate enzyme immunoassays (EIA) for chlamydial antigens in first catch urine (FCU) from symptomatic and asymptomatic men. Study Design: We conducted five different studies; FCUs and urethral swabs were collected from 1,341 symptomatic and 816 asymptomatic males. Four EIAs (SureCell, Chlamydiazyme, MicroTrak and IDEIA) were tested on the FCU sediments. Results: Prevalence of chlamydia by tissue culture isolation was 6% for asymptomatic and 14% for symptomatic men. With symptomatic males, the EIA sensitivities and specificities were: SureCell 85% and 97%, IDEIA 82% and 98%, MicroTrak 86% and 99%, and Chlamydiazyme 91% and 95%. For asymptomatic men, Chlamydiazyme sensitivity was 35% with frozen urine vs 77% with fresh urine. Overall, tissue culture sensitivity was about 90%. Conclusion: EIA results on FCU sediments are comparable to that of tissue culture isolation on urethral swabs. In many settings, FCU may be the specimen of choice for diagnosing chlamydial infections in men., Testing first catch urine samples with enzyme immunoassays (EIAs) appears to provide a relatively effective, non-invasive test for chlamydial infections. Chlamydia is a sexually transmitted disease. Those who are infected may or may not have symptoms. Both urine and urethral swab samples were taken from 816 men without signs of infection and 1,341 men with symptoms of infection. Four EIAs were evaluated. They included Chlamydiazyme, Kodak SureCell, Syva MicroTrak EIA and IDEIA. Results from the urethral swabs were compared with results from the EIAs. Six percent of the men without symptoms and 14% of the men with symptoms tested positive for chlamydial infection by the urethral swab tests. The EIAs detected from 82% to 91% of chlamydial infections. Chlamydia was detected less frequently in frozen urine samples. The urethral swab test detected approximately 90% of chlamydial infections.

Background and Objectives: Chlamydia trachomatis antigen testing of clinical specimens is replacing culture as the test of choice. Because of a potential for false positive results in low prevalence populations, there is an apparent need for confirming specimens positive by enzyme immunoassay (EIA). Goal of this Study: To examine specimens falsely positive in the Chlamydiazyme EIA assay according to gender and specimen type. Study Design: Testing of genitourinary specimens from men and women consecutively enrolled from five health care delivery sources in an urban Canadian population. All specimens were initially tested in the Chlamydiazyme test and all positives repeated in a confirmatory blocking assay provided by the manufacturer. Additional confirmatory testing was performed using immunofluorescence (IF) staining for C. trachomatis elementary bodies (EB's) and polymerase chain reaction (PCR). Results: From Jan. 1, 1990 to June 1, 1991, multiple specimens from 656 men and 5,628 women of varying population prevalences were screened. EIA-positive specimens from women had a repeat negative rate of 22% to 27% from cervical swabs and 29% from urethral swabs. Male urethral swabs had a high repeat negative rate of 22% when EIA was the only positive test, but 2.4% when the specimen was positive by EIA and culture. EIA-positive first void urine (FVU) specimens from men had a repeat negative rate of 8.7% as opposed to 17% to 32% from women. Only 1.7% (2/115) of male FVU did not block compared to rates of 47% (22/47) to 80% (4/5) in FVU from women. Analysis of EIA optical densities (OD's) and EB counts showed an association between the absorbance range 0.1 to 1.4 OD and 0-85 EB's. The greatest number of EB's and highest OD's were seen with cervical specimens, followed by urine and urethral specimens in women infected at all three specimens. All 55 specimens that did not confirm in the blocking test had no EB's and a convenience sample of seven were negative by PCR. All of a subset of 50 blocked specimens contained EB's or were positive by PCR. Conclusions: Although a variable proportion of specimens may not repeat positive in the EIA, use of the blocking reagent to confirm the repeat positives is highly recommended and the rate of blocking may be heavily influenced by gender and specimen type., Gender and specimen type may affect the prevalence of false-positive test results on the Chlamydiazyme enzyme immunoassay (EIA). The Chlamydiazyme EIA is a laboratory test used to diagnose infections of the urogenital tract caused by Chlamydia trachomatis. Researchers used different methods to test multiple specimens from 6,284 individuals who were initially tested for chlamydial infection using the Chlamydiazyme EIA. Twenty-two percent to 27% of the specimens taken from women by cervical swabs had false-positive results on the Chlamydiazyme EIA. Twenty-nine percent of the specimens taken from women by urethral swabs had false-positive results. In men, 22% of specimens taken from urethral swabs had false-positive results on the Chlamydiazyme EIA. False-positive test results were more prevalent among urine specimens taken from men than among those from women.

To determine limitations in commonly used methods for detection of Chlamydia trachomatis, 601 genitourinary specimens from patients in a sexually transmitted disease clinic were examined with quantitative cultures and by 2 different direct antigen tests, immunofluorescence (Micro Trak; Syva Company, Palo Alto, CA) and enzyme immunoassay (Chlamydiazyme; Abbott Laboratories, North Chicago, IL). Genital specimens were held no longer than 5 hours (at 4 [degrees] C) prior to inoculation for culture; 28% (168/601) were positive. To evaluate the effect of storage on culture efficacy, duplicate specimens were also stored at -70 [degrees] C and brought out subsequently for culture a second time. Only 32% (8/25) of specimens cultured within 5 hours and having 100 inclusions; 50% (22/44) with 10-100 inclusions; and only 11% (6/53) with

An enzyme immunoassay (EIA; AntigEnz Chlamydia; Northumbria Biologicals, Northumberland, United Kingdom) and a polymerase chain reaction (PCR) assay (Genemed Biotechnologies, San Francisco, CA) were evaluated for the detection of Chlamydia trachomatis in urogenital specimens. Of 324 specimens, 23 were positive by cycloheximide-treated McCoy's cell culture method. Of 23 culture-positive specimens, 20 and 22 were found to be positive by EIA and PCR, respectively. Among 301 culture-negative samples, 4 were found to be positive by both PCR and EIA, 2 were PCR-positive and EIA-negative and 3 PCR-negative and culture-negative specimens were found to be positive by EIA. In comparing nonculture methods with cell culture technique, combined sensitives of 87.0% (90.9% in men and 83.3% in women) and 95.6% (90.9% in men and 100% in women), and specificities of 97.7% (99.4% in men and 95.7% in women) and 98.0% (99.4% in men and 96.5% in women) are achieved by EIA and PCR, respectively. The PCR proved to be the more sensitive of these two nonculture methods, and it can be used for the rapid diagnosis of C. trachomatis urogenital infection.

Genital Chlamydia trachomatis infection is believed to be the most prevalent sexually transmitted disease in the US. This sexually transmitted disease frequently goes unnoticed and is a major threat to health in women due to the clinical consequences, which include salpingitis, chronic pelvic pain, endometritis, ectopic pregnancy, and infertility. Although a variety of laboratory tests are used for the identification of C. trachomatis, many are not conclusive or accurate as a diagnostic tool for acute infection. A culture is the most accurate laboratory test for the diagnosis of this infection; however, it is expensive, not always available, and is not a rapid diagnostic tool. The enzyme-linked immunosorbent assay (ELISA) test has a high sensitivity (able to detect the organism 85 to 89 percent of the time) and a high specificity (able to differentiate the organism form others 95 to 97 percent of the time). A study was conducted to evaluate test-of-cure methods for genital C. trachomatis infections. Of 373 college-aged women who tested positive for C. trachomatis by ELISA, 75 were enrolled in a treatment study. Treatment with tetracycline 500 mg was prescribed four times a day for seven days. The ELISA test was performed 10 days following initiation of treatment. This method was a reliable test of cure for genital C. trachomatis infections in the women studied and resolution of the infection was confirmed by culture. (Consumer Summary produced by Reliance Medical Information, Inc.), Convenient, reliable tests of cure for genital chlamydial infections have not been evaluated. Cervical appearance, endocervical Gram stain, enzyme immunoassay, and culture for Chlamydia trachomatis were evaluated during a pretreatment visit and at two subsequent randomized test-of-cure visits for 64 nongravid women with endocervical C trachomatis of 3544 patients screened. There were no useful correlations between C trachomatis resolution and cervical appearance. Endocervical Gram stain was determined to be unreliable for test-of-cure use. Both C trachomatis culture and enzyme-linked immunosorbent assay (ELISA) were shown to be effective for test-of-cure evaluation. The ELISA test became reliably negative 10 days after initiation of treatment and 1 to 5 days after the clearance of viable organisms detected by culture (P = .03). Convenience and cost considerations favor antigen detection methods. This study suggests that antigen detection methods can be used for situations in which test of cure is indicated, such as therapy noncompliance, circumstances supporting reinfection, pregnancy, complicated infections, requests for psychological reassurance, and evidence of persistent cervicitis. J FAM PRACT 1990; 31:36-41., Genital Chlamydia trachomatis infection in women has emerged as a problem of major public health importance. Although the true incidence of genital C trachomatis is unknown, it is now thought [...]

Female genital chlamydial infection is a sexually transmitted disease that can cause permanent damage to health and fertility if left untreated. The nonspecific and silent nature of symptoms and signs, the changing sexual behavior of men and women, and the lack of widely available diagnostic tests, are responsible for the increased incidence of chlamydial infections among women. Accurate diagnosis is therefore important. Detection of chlamydial infections by family practice physicians requires skill in evaluating laboratory results. Sensitivity and specificity of the available laboratory tests must be fully understood since false positive and false negative results may occur. Increased risk of chlamydial infection must be considered and consultation regarding sexual history is important with patients in whom a positive test result may be possible. Upon completion of treatment for a chlamydial infection and during follow-up consultation, laboratory testing is usually repeated as a test of cure. In addition to discussing test results with patients, family practice physicians should discuss the importance of the treatment of sexual partners and the importance of prevention. In an article in the July 1990 issue of The Journal of Family Practice, the accuracy of the enzyme-linked immunosorbent assay (ELISA) test for identification of Chlamydia trachomatis as a test of cure is discussed. (Consumer Summary produced by Reliance Medical Information, Inc.), The laboratory diagnosis of female genital chlamydial infections is a difficult area for family physicians, many of whom now realize the disastrous effect on family life that an untreated infection [...]