Comparison among performances of a ligase chain reaction-based assay and two enzyme immunoassays in detecting Chlamydia trachomatis in urine specimens from men with nongonococcal urethritis.

1996 ◽  
Vol 34 (7) ◽  
pp. 1708-1710 ◽  
Author(s):  
T Deguchi ◽  
M Yasuda ◽  
M Uno ◽  
K Tada ◽  
H Iwata ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Chain Reaction ◽  
Ligase Chain Reaction ◽  
Enzyme Immunoassays ◽  
Nongonococcal Urethritis ◽  
Urine Specimens

scholarly journals Genotyping of Chlamydia trachomatis in Urine Specimens Will Facilitate Large Epidemiological Studies

1998 ◽  
Vol 36 (10) ◽  
pp. 3077-3078 ◽  
Author(s):  
Servaas A. Morré ◽  
Robert Moes ◽  
Irene Van Valkengoed ◽  
Joan P. Boeke ◽  
Jacques T. M. van Eijk ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Rflp Analysis ◽  
Epidemiological Studies ◽  
Chain Reaction ◽  
Typing Method ◽  
Ligase Chain Reaction ◽  
Positive Urine ◽  
Urine Specimens

The serovars of Chlamydia trachomatis-positive urine specimens (n = 81; as detected by PCR and ligase chain reaction) were successfully analyzed in 94% of cases byomp1 PCR-based RFLP analysis. The use of urine specimens and this simple and sensitive typing method will greatly facilitate epidemiological studies of C. trachomatis serovar distribution in asymptomatic C. trachomatis infections in both females and males.

Pooling Cervical Swabs and Testing by Ligase Chain Reaction Are Accurate and Cost-Saving Strategies for Diagnosis ofChlamydia trachomatis

2000 ◽  
Vol 38 (7) ◽  
pp. 2480-2483 ◽  
Author(s):  
J. Kapala ◽  
D. Copes ◽  
A. Sproston ◽  
J. Patel ◽  
D. Jang ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Cost Saving ◽  
Nucleic Acids ◽  
Positive Control ◽  
Test Results ◽  
Chain Reaction ◽  
Ofchlamydia Trachomatis ◽  
Ligase Chain Reaction ◽  
Pooling Strategies ◽  
Urine Specimens

Specimen pooling to achieve efficiency when testing urine specimens for Chlamydia trachomatis nucleic acids has been suggested. We pooled endocervical swabs from 1,288 women and also tested individual swabs by ligase chain reaction (LCR). Out of 53 positive specimens, pools of 4 or 8 specimens missed two positives, providing 96.2% accuracy compared to individual test results. Dilution and positive-control spiking experiments showed that negative specimens with inhibitors of LCR in the pool reduced the signal. Conversely, two extra positives, detected only through pooling, were negative by individual testing but became positive after storage, suggesting that fresh positive specimens with labile inhibitors may be positive in a pool because of dilution of inhibitors. For this population of women with a 4% prevalence of C. trachomatis infection, substantial savings in cost of reagents (55 to 63%) and technologist time (50 to 63%) made pooling strategies a desirable alternative to individual testing.

scholarly journals Urine Specimens from Pregnant and Nonpregnant Women Inhibitory to Amplification of Chlamydia trachomatis Nucleic Acid by PCR, Ligase Chain Reaction, and Transcription-Mediated Amplification: Identification of Urinary Substances Associated with Inhibition and Removal of Inhibitory Activity

1998 ◽  
Vol 36 (11) ◽  
pp. 3122-3126 ◽  
Author(s):  
J. Mahony ◽  
S. Chong ◽  
D. Jang ◽  
K. Luinstra ◽  
M. Faught ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Chlamydia Trachomatis ◽  
Pregnant Women ◽  
False Negative ◽  
Nucleic Acid Amplification ◽  
Urine Specimen ◽  
Chain Reaction ◽  
Ligase Chain Reaction ◽  
Negative Results ◽  
Urine Specimens

The presence of endogenous amplification inhibitors in urine may produce false-negative results for the detection of Chlamydia trachomatis nucleic acids by tests such as PCR, ligase chain reaction (LCR), and transcription-mediated amplification (TMA). Consecutive urine specimens from 101 pregnant women and 287 nonpregnant women submitted for urinalysis were processed for C. trachomatis detection. Aliquots were spiked with the equivalent of one C. trachomatis elementary body and were tested by three commercial assays: AMPLICOR CT/NG, Chlamydia LCX, and Chlamydia TMA. The prevalence of inhibitors resulting in complete inhibition of amplification was 4.9% for PCR, 2.6% for LCR, and 7.5% for TMA. In addition, all three assays were partially inhibited by additional urine specimens. Only PCR was more often inhibited by urine from pregnant women than by urine from nonpregnant women (9.9 versus 3.1%;P = 0.011). A complete urinalysis including dipstick and a microscopic examination was performed. Logistic regression analysis revealed that the following substances were associated with amplification inhibition: beta-human chorionic gonadotropin (odds ratio [OR], 3.3) and crystals (OR, 3.3) for PCR, nitrites for LCR (OR, 14.4), and hemoglobin (OR, 3.3), nitrites (OR, 3.3), and crystals (OR, 3.3) for TMA. Aliquots of each inhibitory urine specimen were stored at 4 and −70°C overnight or were extracted with phenol-chloroform and then retested at dilutions of 1:1, 1:4, and 1:10. Most inhibition was removed by storage overnight at 4 or −70°C and a dilution of 1:10 (84% for PCR, 100% for LCR, and 92% for TMA). Five urine specimens (three for PCR and two for TMA) required phenol-chloroform extraction to remove inhibitors. The results indicate that the prevalence of nucleic acid amplification inhibitors in female urine is different for each technology, that this prevalence may be predicted by the presence of urinary factors, and that storage and dilution remove most of the inhibitors.

scholarly journals Use of Ligase Chain Reaction with Urine versus Cervical Culture for Detection of Chlamydia trachomatis in an Asymptomatic Military Population of Pregnant and Nonpregnant Females Attending Papanicolaou Smear Clinics

1998 ◽  
Vol 36 (5) ◽  
pp. 1300-1304 ◽  
Author(s):  
Charlotte A. Gaydos ◽  
M. Rene Howell ◽  
Thomas C. Quinn ◽  
Joel C. Gaydos ◽  
Kelly T. McKee
Keyword(s):  
Chlamydia Trachomatis ◽  
Pregnant Women ◽  
Fluorescent Antibody ◽  
Chain Reaction ◽  
Military Population ◽  
Predictive Values ◽  
Papanicolaou Smear ◽  
Ligase Chain Reaction ◽  
Culture Positive ◽  
Urine Specimens

Ligase chain reaction (LCR) (Abbott Laboratories, Abbott Park, Ill.) with first-catch urine specimens was used to detectChlamydia trachomatis infections in 465 asymptomatic military women attending clinics for routine Papanicolaou smear tests. Results were compared to results of cervical culture to determine the sensitivity of the urine LCR and the possible presence of inhibitors of amplification in pregnant and nonpregnant women. Discrepant results for LCR and culture were resolved by direct fluorescent antibody staining of culture sediments, two different PCR assays, and LCR for the outer membrane protein 1 gene. The prevalence of Chlamydia in specimens by urine LCR was 7.3% compared to 5% by culture. For 434 women with matching specimens, there were 11 more specimens positive by LCR than were positive by culture, of which all but one were determined to be true positives. There were four culture-positive, LCR-negative specimens, all from nonpregnant women. The sensitivity, specificity, and positive and negative predictive values of urine LCR after discrepant results were resolved were 88.6, 99.7, 96.9, and 99.0%, respectively. The sensitivity of culture was 71.4%. From the 148 pregnant women (prevalence by LCR, 6.8%), there were no patients who were cervical culture positive and urine LCR negative to indicate the presence in pregnant women of inhibitors of LCR. Additionally, a subset of 55 of the LCR-negative frozen urine specimens from pregnant women that had been previously processed in LCR buffer were inoculated with 5 cell culture inclusion forming units of C. trachomatis each and retested by LCR; all tested positive, indicating the absence of inhibitors of LCR in urine from these pregnant women. The use of LCR testing of urine specimens from asymptomatic women, whether pregnant or not, offers a sensitive and easy method to detect C. trachomatis infection in women.

scholarly journals Evaluation of the Abbott LCx Ligase Chain Reaction Assay for Detection of Chlamydia trachomatis and Neisseria gonorrhoeae in Urine and Genital Swab Specimens from a Sexually Transmitted Disease Clinic Population

1998 ◽  
Vol 36 (6) ◽  
pp. 1630-1633 ◽  
Author(s):  
Karen C. Carroll ◽  
William E. Aldeen ◽  
Michael Morrison ◽  
Roberta Anderson ◽  
Deborah Lee ◽  
...  
Keyword(s):  
Data Analysis ◽  
Chlamydia Trachomatis ◽  
Neisseria Gonorrhoeae ◽  
Positive Result ◽  
Transmitted Disease ◽  
Urine Samples ◽  
Chain Reaction ◽  
Ligase Chain Reaction ◽  
Pilin Gene ◽  
Urine Specimens

The Abbott LCx ligase chain reaction (LCR) assay for the simultaneous detection of Chlamydia trachomatis andNeisseria gonorrhoeae was evaluated by using swab and urine specimens from 562 patients. C. trachomatis results by LCR were compared to those by the Gen-Probe PACE 2 assay, whereas N. gonorrhoeae results by LCR were compared to those by culture. The Gen-Probe and LCR assays were performed according to the manufacturers’ instructions. Gram-negative diplococci growing on modified Thayer-Martin medium were confirmed as N. gonorrhoeae by the GonoGen II assay. Supplemental data analysis was performed by major outer membrane protein PCR for C. trachomatis and probes for pilin gene detection for N. gonorrhoeae. A true-positive result for each pathogen was defined as a positive result for all three or two of three assays. Overall agreement among the six assays was 94.8%. C. trachomatis prevalence was 16.2%; N. gonorrhoeae prevalence was 5.5%. The overall sensitivity and specificity, respectively, for each test (after supplemental data analysis) were as follows: for C. trachomatis, Gen-Probe, 65.9 and 100%; LCR on urine, 90.1 and 100%; LCR on swab specimens, 96.7 and 100%; and for N. gonorrhoeae, culture, 80.6 and 100%; LCR on urine, 93.5 and 99.8%; and LCR on swab specimens, 96.8 and 100%. For women, theN. gonorrhoeae culture was very insensitive compared to its performance in men (58.3 versus 94.7%, respectively). ForC. trachomatis, the Gen-Probe assay’s sensitivity was lower for men than for women (62.3 versus 71.1%, respectively). The sensitivity for C. trachomatis detection by LCR on urethral and cervical swab specimens was 96.2 and 97.4% for men and women, respectively. For men, swab results were slightly better than urine results for both pathogens (sensitivity for C. trachomatis in swab and urine specimens, 96.2 and 92.5%, respectively; sensitivity for N. gonorrhoeae in swab and urine specimens, 100 and 94.7%, respectively), while for women, cervical swabs were superior in sensitivity to urine samples for detecting C. trachomatis (swab, 97.4%; urine, 81.6%) and equivalent for N. gonorrhoeae (swab, 92.3%; urine, 91.6%). The LCx LCR appears to be both sensitive and specific for the detection of C. trachomatis andN. gonorrhoeae when performed on urine or genital swab samples. Swab samples had better sensitivity than urine samples for the detection of both pathogens.

Detection of Chlamydia trachomatis in urine specimens from women by ligase chain reaction.

1995 ◽  
Vol 33 (4) ◽  
pp. 898-900 ◽  
Author(s):  
M Bassiri ◽  
H Y Hu ◽  
M A Domeika ◽  
J Burczak ◽  
L O Svensson ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Chain Reaction ◽  
Ligase Chain Reaction ◽  
Urine Specimens

scholarly journals Pooling Urine Samples for Ligase Chain Reaction Screening for Genital Chlamydia trachomatis Infection in Asymptomatic Women

1998 ◽  
Vol 36 (2) ◽  
pp. 481-485 ◽  
Author(s):  
Katherine A. Kacena ◽  
Sean B. Quinn ◽  
M. René Howell ◽  
Guillermo E. Madico ◽  
Thomas C. Quinn ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Cost Savings ◽  
Urine Samples ◽  
Chain Reaction ◽  
Ligase Chain Reaction ◽  
Chlamydia Trachomatis Infection ◽  
Population Prevalence ◽  
Pooled Samples ◽  
Asymptomatic Women ◽  
Urine Specimens

The accuracy of pooling urine samples for the detection of genitalChlamydia trachomatis infection by ligase chain reaction (LCR) was examined. A model was also developed to determine the number of samples to be pooled for optimal cost savings at various population prevalences. Estimated costs included technician time, laboratory consumables, and assay costs of testing pooled samples and retesting individual specimens from presumptive positive pools. Estimation of population prevalence based on the pooled LCR results was also applied. After individual urine specimens were processed, 568 specimens were pooled by 4 into 142 pools and another 520 specimens were pooled by 10 into 52 pools. For comparison, all 1,088 urine specimens were tested individually. The sample-to-cut-off ratio was lowered from 1.0 to 0.2 for pooled samples, after a pilot study which tested 148 samples pooled by 4 was conducted. The pooling algorithm was 100% (48 of 48) sensitive when samples were pooled by 4 and 98.4% (61 of 62) sensitive when samples were pooled by 10. Although 2.0% (2 of 99) of the negative pools of 4 and 7.1% (1 of 14) of the negative pools of 10 tested presumptive positive, all samples in these presumptive-positive pools were negative when retested individually, making the pooling algorithm 100% specific. In a population with 8% genital C. trachomatis prevalence, pooling by four would reduce costs by 39%. The model demonstrated that with a lower prevalence of 2%, pooling eight samples would reduce costs by 59%. Pooling urine samples for detection of C. trachomatis by LCR is sensitive, specific, and cost saving compared to testing individual samples.

scholarly journals Comparison of the ligase chain reaction with cell culture for the diagnosis of Chlamydia trachomatis infection in women.

1996 ◽  
Vol 49 (2) ◽  
pp. 116-119 ◽  
Author(s):  
G L Ridgway ◽  
G Mumtaz ◽  
A J Robinson ◽  
M Franchini ◽  
C Carder ◽  
...  
Keyword(s):  
Cell Culture ◽  
Chlamydia Trachomatis ◽  
Chain Reaction ◽  
Ligase Chain Reaction ◽  
Chlamydia Trachomatis Infection
Sign in / Sign up

Export Citation Format

Share Document