TThe Syva MicroTrak Chlamydia enzyme immunoassay (EIA; Syva Company, San Jose, Calif.) with cytospin and direct fluorescent-antibody assay (DFA) confirmation was evaluated on 43,630 urogenital specimens over a 1-year period in the Provincial Laboratory in Regina, Saskatchewan, Canada. This was a two-phase study intended to define a testing algorithm for Chlamydia trachomatis that would be both highly accurate and cost-effective in our high-volume (> 3,000 tests per month) laboratory. The prevalence of C. trachomatis infection in our population is moderate (8 to 9%). In phase 1, we tested 6,022 male and female urogenital specimens by EIA. All specimens with optical densities above the cutoff value and those within 30% below the cutoff value were retested by DFA. This was 648 specimens (10.8% of the total). A total of 100% (211 of 211) of the specimens with optical densities equal to or greater than 1.00 absorbance unit (AU) above the cutoff value, 98.2% (175 of 178) of the specimens with optical densities of between 0.500 and 0.999 AU above the cutoff value, and 83% (167 of 201) of the specimens with optical densities within 0.499 AU above the cutoff value were confirmed to be positive. A total of 12% (7 of 58) of the specimens with optical densities within 30% below the cutoff value were positive by DFA. In phase 2, we tested 37,608 specimens (32,495 from females; 5,113 from males) by EIA. Only those specimens with optical densities of between 0.499 AU above and 30% below the cutoff value required confirmation on the basis of data from phase 1 of the study. This was 4.5% of all specimens tested. This decrease in the proportion of specimens requiring confirmation provides a significant cost savings to the laboratory. The testing algorithm gives us a 1-day turnaround time to the final confirmed test results. The MicroTrak EIA performed very well in both phases of the study, with a sensitivity, specificity, positive predictive value, and negative predictive value of 96.1, 99.1, 90.3, and 99.7%, respectively, in phase 2. We suggest that for laboratories that use EIA for Chlamydia testing, a study such as this one will identify an appropriate optical density range for confirmatory testing for samples from that particular population.
Urethral specimens from 172 men who attended sexually transmitted disease clinics in the Moscow Oblast were examined for Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium by nucleic acid amplification tests. N. gonorrhoeae was detected in the urethra of 41 (24%) of the 172 men and C. trachomatis in 57 (33%). The latter occurred in 15 (36%) of the 41 men who were infected by N. gonorrhoeae and in 42 (32%) of 131 uninfected by gonococci. Of the 42 men uninfected by gonococci but chlamydia infected, 39 (93%) had symptoms and/or signs of urethritis. M. genitalium was detected in 45 (26%) of the 172 men, in nine (22%) of the 41 men infected with N. gonorrhoeae and in 12 (21%) infected with C. trachomatis. M. genitalium was detected alone in 25 (28%) of the 89 men uninfected by either gonococci or C. trachomatis. Of these 25 men, 24 (96%) had urethral symptoms and signs of inflammation, a proportion significantly more than experienced by the 64 men uninfected by any of the microorganisms. Of the 31 men who apparently had no symptoms or signs of urethritis, only three (10%) were infected by M. genitalium. The data provide evidence for the pathogenicity and frequent occurrence of M. genitalium in men in Moscow and presumably elsewhere in Russia.
Many countries have witnessed a disturbing increase in cases of Chlamydia trachomatis infection despite enhanced control programs. Since the goal of Chlamydia control is to prevent reproductive complications such as pelvic inflammatory disease and ectopic pregnancy, an understanding of recent trends in these conditions is needed to fully evaluate the effect of control efforts.
We analyzed 2 provincial, comprehensive health services administrative databases (encompassing hospitalizations and all physician-delivered services) for pelvic inflammatory disease and ectopic pregnancy trends from 1992 through 2009 in women of reproductive age in British Columbia, Canada. Trends were compared to provincial Chlamydia surveillance data by time-series analysis, using the cross-correlation function method and Granger causality testing.
Chlamydia cases substantially increased from 1992 through 2009. Inpatient, outpatient, and total diagnoses of pelvic inflammatory disease and ectopic pregnancy declined from 1992 through 2003. After 2003, pelvic inflammatory disease rates continued to fall, while ectopic pregnancy rates significantly increased. The male Chlamydia urethritis rate increased from 39.4 to 173.6 cases/100,000 from 1996 to 2009.
In the context of increasing Chlamydia infection rates, the reproductive complications of Chlamydia infection in women are declining overall. A recent increase in rates of ectopic pregnancies is cause for concern.
Comparison of first void urine and urogenital swab specimens for detection of Mycoplasma genitalium and Chlamydia trachomatis by polymerase chain reaction in patients attending a sexually transmitted disease clinic.
The objective of this study was to compare urogenital swab specimens and first void urine (FVU) specimens from male and female patients at a sexually transmitted disease clinic for the detection of Mycoplasma genitalium and Chlamydia trachomatis infections using in-house, inhibitor-controlled polymerase chain reaction (PCR).
Urethral swabs and FVU were collected from 1856 men and 753 women who also had a cervical swab collected. A positive diagnosis of infection was made if any 1 of the specimens tested positive and were confirmed in a second PCR assay targeting independent genes.
M. genitalium DNA and C. trachomatis DNA were detected in 126 (6.8%) and 246 (13.3%) of the male sample sets and in 51 (6.8%) and 73 (9.7%) of the female specimen sets, respectively. Using our in-house PCR and sample preparation methods, FVU was found to be the most sensitive diagnostic specimen for both pathogens, but for optimal sensitivity, it should be supplemented with a cervical specimen in women. In a small subset of female FVUs, storage at -20 degrees C led to false-negative M. genitalium PCR results in 27% of specimens found positive when a sample preparation was performed before freezing. The age-specific prevalence of M. genitalium in men was almost constant between 18 and 45 years of age in contrast to C. trachomatis infections, which were more common in younger men.
Urine appeared to be a better diagnostic specimen than the urethral swab for M. genitalium and C. trachomatis detection by PCR in this cohort of sexually transmitted disease clinic attendees but should be supplemented with a cervical specimen in women.
Noninvasive urine samples have been used to diagnose Chlamydia trachomatis infections, with the assumption that the first-void urine (FVU), defined as the first 20 to 30 ml at any micturition, would be the optimal collection. We compared testing technologies on first, second, and third volumes for diagnosis.
The goal was to test in nonculture assays three sequential volumes of urine from men also undergoing urethral swabbing for C trachomatis culture specimens.
A total of 237 men attending an STD clinic (C trachomatis prevalence, 11%) collected three containers of urine (each containing 20-30 mL) for testing in four nonculture assays. A urethral swab specimen was tested in cell culture.
The numbers of men positive by testing of FVU with nucleic acid amplification (LCx chlamydia), nucleic acid hybridization (PACE 2), enzyme immunoassay (Chlamydiazyme), and a leukocyte esterase dipstick were 26, 7, 14, and 11, respectively; urethral culture identified 6 of the infected men. Comparative testing of all voids from the 26 men positive by the FVU assays demonstrated a reduction of LCx-positives. Non-amplified-test positivity declined precipitously in subsequent voids, approaching zero in the third void. The presence of symptoms and time of last void up to 8 hours had little effect on the number of positives detected by LCx of FVU.
Amplified testing of FVU was most effective for diagnosing infection in these men.