First-catch Urine Specimens Research Articles

Should we still be testing for asymptomatic non-specific urethritis in departments of genitourinary medicine?

It has recently been advocated that non-invasive testing with first-catch urine specimens using nucleic acid amplification techniques, to detect Chlamydia trachomatis and Neisseria gonorrhoeae, should replace routine microscopy on asymptomatic men. Although it is assumed that this strategy will be cost effective, the available evidence suggests that this will result in fewer sexually transmitted infections being averted than continuing the current practice of screening for urethritis and testing for both microorganisms in asymptomatic men. This review article summarizes the available evidence and argues that research is urgently needed in order to properly evaluate the cost-effectiveness of detecting urethritis in asymptomatic men.

Utility of Pooled Urine Specimens for Detection of Chlamydia trachomatis and Neisseria gonorrhoeae in Men Attending Public Sexually Transmitted Infection Clinics in Mumbai, India, by PCR

Pooling urogenital specimens for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae by nucleic acid amplification tests is an attractive alternative to individual testing. As pooling can reduce the costs of testing as well as labor, it has been advocated for use in resource-poor settings. However, it has neither been widely adopted nor evaluated for use in developing countries. We evaluated the practical use of pooling first-catch urine (FCU) specimens for the detection of C. trachomatis and N. gonorrhoeae from 690 men in Mumbai, India, by PCR. FCU, urethral smears, and swabs were collected from men seen at two sexually transmitted infection (STI) clinics. All laboratory testing was done at the Lokmanya Tilak General Hospital. Gram stain smears and culture isolation for N. gonorrhoeae were performed. Each FCU was tested individually and in pools using the Roche Amplicor PCR for C. trachomatis and N. gonorrhoeae with an internal control for inhibition. Specimen pools consisted of aliquots from five consecutively processed FCUs combined into an amplification tube. An optical density reading of > or =0.20 indicated a pool for which subsequent testing of individual samples was required. Prevalence by PCR on single specimens was 2.2% (15/690) for C. trachomatis and 5.4% (37/690) for N. gonorrhoeae. Compared to individual FCU results, pooling for C. trachomatis and N. gonorrhoeae had an overall sensitivity of 96.1% (50/52). Specificity was 96.5% (83/86) in that three pools required single testing that failed to identify a positive specimen. Pooling missed two positive specimens, decreased the inhibition rate, and saved 50.3% of reagent costs. In this resource-limited setting, the use of pooling to detect C. trachomatis and N. gonorrhoeae by PCR proved to be a simple, accurate, and cost-effective procedure compared to individual testing.

Volume Effect on Sensitivity of Nucleic Acid Amplification Tests for Detection of Chlamydia trachomatis in Urine Specimens from Females

Nucleic acid amplification tests (NAATs) for the detection of Chlamydia trachomatis are routinely used on first-catch urine (FCU) specimens. We analyzed data from a head-to-head comparison of NAATs on female FCU specimens and found that the volume of urine collected could affect test performance.

Cervicovaginal coinfections with human papillomavirus and chlamydia trachomatis

Human papillomavirus (HPV) and Chlamydia trachomatis (CT) are the two most common sexually transmitted pathogens, and infection with either reportedly was associated with cervical intraepithelial neoplasia (CIN) in women. In view of their similar mode of transmission, CT infection was examined as a possible HPV cofactor in the etiology of CIN disease. In total, 129 women were included in the study, of whom 80 were negative (mean age 34.17 ± 6.9) and 49 were positive (mean age 33.16 ± 6.8) for HPV DNA (assessed by PCR). CT DNA was determined in endocervical and first-catch urine specimens by PCR. Whereas HPV-positive and HPV-negative women were similar with respect to age ( p = 0.419) and pregnancy outcomes ( p = 0.628), the number of smokers ( p = 0.001), women with multiple male sex partners ( p = 0.002) or with abnormal cytology ( p < 0.001) was higher in the HPV-positive group. There was an increase in CT infection rate in HPV-positive (29/49) as compared to HPV-negative (10/80) women ( p < 0.01). Within HPV-positive patients, there was no significant difference between CT-positive and CT-negative patients with regards to the risk factors studied. Collectively, this suggests that CT infection is a cofactor of HPV in CIN disease development, possibly by modulating the host’s immunity and/or precipitation of chronic inflammation.

Screening for Neisseria gonorrhoeae and Chlamydia trachomatis at entertainment venues among men who have sex with men.

To assess the prevalence and increase awareness of Neisseria gonorrhoeae and Chlamydia trachomatis infections among men who have sex with men, a screening program was conducted at three inner-city homosexual entertainment venues and one community function. Each venue was accessed twice over a 3-month period between March and June 2000. First-catch urine specimens were collected for analysis by polymerase chain reaction (PCR), and throat swabs were collected for culture and PCR. A total of 202 men were tested during the 7 screening nights, including 16 who were tested more than once. From the 186 men tested for the first time, 184 urine specimens were collected, of which 8 (4.3%; 95% CI, 1.9-7.8%) were PCR-positive for C trachomatis and 1 (0.5%; 95% CI, 0-2.1%) was PCR-positive for N gonorrhoeae. Of the 161 throat swabs collected, none were positive for C trachomatis or N gonorrhoeae. C trachomatis is a potentially significant pathogen in this population of urban homosexual men. Screening programs such as these are valuable as health-promotion exercises.

Which Test is Best for Chlamydia? *

Nucleic acid amplification tests are now the tests of choice for diagnosing Chlamydia trachomatis infection. For the first time there are diagnostic tests for Chlamydia trachomatis that are more sensitive than tissue culture. Another major advantage is that they can be used with first-catch urine specimens and vaginal swabs. It is thus possible to test for genital chlamydial infection without using invasive specimen collection methods.

Urethral syndromes in children.

1. Walid Farhat, MD* 2. Gordon McLorie, MD* 1. 2. *Division of Urology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada. Objectives After completing this article, readers should be able to: 1. Describe the evaluation of a child suspected of having urethritis. 2. Delineate the screening tests that have the highest yield for urethritis in young children. 3. List components of a behavioral modification approach to treating dysfunctional voiding. 4. Compare and contrast physical findings in gonococcal and nongonococcal urethritis. Inflammation of the urethra (urethritis) may be due to infection, trauma, allergy, foreign body, or an undetermined factor. Certain characteristics distinguish urethritis in the pediatric population from that in adults. First, urethritis in adults and adolescents has an infectious etiology and always is the result of sexual contact; infectious urethritis in the pediatric age group is uncommon, except in sexually active adolescents or children who have been sexually abused by an adult who has the disease. Second, the variability and nonspecificity of a variety of noninfectious urethral pathologies may mimic infectious urethritis in children. Children who have urethritis may present with irritative voiding symptoms, such as dysuria, urgency, or frequency; possible urethral discharge; initial hematuria; or blood spotting on the underwear. Patients suspected of having urethritis are evaluated with a detailed history, physical examination, urethral smear, or urine culture. In girls, examination may show evidence of vaginitis, which is a common cause of dysuria after urinary tract infection, labial adhesions, or even sexual abuse; in males, results of the examination frequently are inconclusive. In infants, young children, and sexually inactive adolescents, screening tests that have the highest yield include urinalysis and abdominal ultrasonography (US); uroflow is reserved for toilet-trained children. The urine should be examined for evidence of infection or hematuria. Abdominal US can diagnose a variety of abnormalities, including bladder stone or inflammation, ureterocele, foreign body, or tumor. Uroflow is a noninvasive urodynamics test that assesses the ability to initiate voiding on command, quantitates …

Pooling of urine specimens for PCR testing: a cost saving strategy for Chlamydia trachomatis control programmes.

OBJECTIVES: To evaluate pooling of first catch urine (FCU) specimens as a cost effective strategy for chlamydia testing. METHODS: Mock specimens were pooled with and without dilution to determine optimal...

Evaluation of the Vidas Chlamydia test to detect and verify Chlamydia trachomatis in urogenital specimens.

The Vidas Chlamydia test (CHL) is an automated enzyme-linked immunofluorescence assay for the detection of Chlamydia trachomatis. Positive and equivocal results are confirmed with a blocking assay. A mouse monoclonal antibody directed against the chlamydial lipopolysaccharides was used for the test. The CHL assay is widely used in Europe, but U.S. experience with it is limited. Three clinical test sites (The Arlington Hospital, Arlington, Va., Indiana University, Indianapolis, and the University of California, San Francisco) compared CHL with tissue culture (TC) for the identification of chlamydia in urogenital specimens (2,453 females and 850 males). True positives (TP) were defined as either TC positive or TC negative and CHL positive by a positive direct fluorescent-antibody assay or PCR test. Overall prevalence was 5.5% for females, 10.3% for male urethral swabs, and 10.7% for combined male TC urethral swabs and CHL with first catch urine (FCU) specimens. Compared to TP, CHL and TC had sensitivities of 89.6 and 94.1% with female cervical swabs and 90.9 and 86.4% with male urethral swabs, respectively. CHL sensitivity was 81.2 for male FCU specimens and 77.7% for matching male TC swabs. There were relatively few false-positive results, with all specificities being >99.4%. With the blocking assay, Vidas CHL specificity was >99.7%. However, male FCU specimen sensitivity was compromised because 9.2% (7 of 76) of the TP were initially positive but were not confirmed. An improvement in the Vidas blocking assay is needed before we can recommend its use with male urine. Alternatively, one could argue that the specificity of the test is so high that a confirmatory assay is not needed. For male and female swabs, the Vidas CHL assay has a performance that is similar to that of TC.

Urethral infection in a workplace population of East African men: evaluation of strategies for screening and management.

Transport workers (n = 504) in Mombasa, Kenya, were screened for urethral infection by history, clinical examination, and laboratory testing of urethral swabs and first-catch urine specimens. The prevalence of Neisseria gonorrhoeae was 3.4%, Chlamydia trachomatis, 3.6%, and Trichomonas vaginalis, 6.0%; more than two-thirds of infections were asymptomatic. A complaint of urethral discharge, dysuria, or both was twice as sensitive as the sign of discharge on physical examination (34.5% vs. 15.5%) in identifying infection. A positive leukocyte esterase dipstick (LED) test on urine predicted infection with a sensitivity of 95.0% and a specificity of 59.3% in symptomatic men and with a sensitivity of 55.3% and a specificity of 82.8% in asymptomatic men. Demographic and behavioral factors were not independent predictors of infection. In resource-poor settings with high prevalences of urethral infection, an effective screening and management strategy would be to treat symptomatic men, as well as asymptomatic men with a positive LED test, for all three infections.

Prevalence of Mycoplasma genitalium in asymptomatic men in Japan.

We aim to clarify the prevalence of Mycoplasma genitalium in asymptomatic men in Japan. First-catch urine specimens were obtained from 187 asymptomatic Japanese men and examined for the presence of M. genitalium using a polymerase chain reaction (PCR)-based assay. Two (1.1%) of 187 first-catch urine specimens were positive for M. genitalium. The prevalence of M. genitalium in urine specimens of asymptomatic men in Japan is lower than that in asymptomatic men in the UK (6%) and Denmark (9%).

Comparison of manual Amplicor PCR, Cobas Amplicor PCR, and LCx assays for detection of Chlamydia trachomatis infection in women by using urine specimens

We compared the Roche Amplicor PCR, Roche Cobas Amplicor PCR, and Abbott LCx assays by using urine specimens for the detection of Chlamydia trachomatis infections in a female population. First-catch urine and endocervical swab specimens were collected from a total of 442 patients. Urine specimens were tested by the manual Roche Amplicor PCR, the automatic Roche Cobas Amplicor PCR, and the Abbott LCx assays as instructed by the manufacturers. For the Cobas Amplicor PCR, the internal control protocol was used for every specimen to reveal the presence of polymerase inhibitors. Cell culture of cervical specimens was used as a reference method. Of 442 patients, 50 (11.3%) were confirmed to have chlamydial infection. The diagnostic sensitivity and specificity of cell culture with cervical swab specimens were 88 and 100%, respectively. With urine specimens the sensitivity and specificity for the manual Amplicor PCR assay were 100 and 99.7%, respectively; those for the automatic Cobas Amplicor PCR assay were 94 and 99.2%, respectively; and those for the LCx assay were 94 and 100%, respectively. Thus, all amplification methods with urine specimens proved to be highly sensitive and specific for the detection of C. trachomatis infection in women. No statistically significant differences in the test performances could be demonstrated for specimens from this population. All three amplification techniques with urine specimens proved to be superior to cell culture with cervical swab specimens in diagnosing C. trachomatis infections in women.

Is urine leukocyte esterase test a useful screening method to predict Chlamydia trachomatis infection in women?

We evaluated the use of the leukocyte esterase test (LET) on first-catch urine specimens from women as a screening test to predict infection with Chlamydia trachomatis. For diagnosis, we used Abbott's ligase chain reaction (LCR) on urine specimens and isolation by tissue culture (TC) on cervical brushes. Of 4,053 women attending sexually transmitted disease and family planning clinics, 4.3% (n = 174) were positive by TC and 5.9% (n = 239) were positive by LCR. When LET was compared to TC, the sensitivity, specificity, positive predictive value, and negative predictive value were 54.0, 67.0, 6.8, and 97.0%, respectively. The corresponding performance of LET versus LCR was 53.1, 67.3, 10.1, and 95.8%. Almost half of the laboratory-confirmed chlamydial infections were negative by LET. The low specificity probably reflects multiple causes of pyuria in women and results in a low positive predictive value. LET is neither sensitive nor specific as a predictor of chlamydial infection and cannot be recommended for use as a screening test for C. trachomatis with first-catch urine samples from females from low- or moderate-prevalence populations.

Noninvasive Tests for Diagnosis of Chlamydia trachomatis Infection: Application of Ligase Chain Reaction to First-Catch Urine Specimens of Women

Ligase chain reaction (LCR) to diagnose Chlamydia trachomatis infection was evaluated using first-catch urine (FCU) specimens from 4053 women. Results were compared with those of cell culture (TC) isolation from cervix (all) and urethra (2812 women). The reference standard was TC positivity or positive LCR for chlamydial plasmid DNA confirmed by direct fluorescent antibody test or LCR for another chlamydial gene. Compared with cervical culture, LCR was 88.2% sensitive and 100% specific. Adding urethral culture increased TC sensitivity from 67.1% to 74% and reduced LCR sensitivity to 85.9%. The prevalence of chlamydial infection was 5% (142/2812) by the dual culture system and 5.9% (165/2812) by LCR on FCU specimens. LCR on FCU specimens is highly sensitive and specific for diagnosing chlamydial infection. It is more sensitive than TC and may well present public health authorities with a useful noninvasive screening test for chlamydial infection in asymptomatic women.

Screening voided urine for Chlamydia trachomatis in asymptomatic adolescent females.

First catch urine (FCU) from 751 asymptomatic adolescent female high school students, with sexual debut, were screened for the presence of Chlamydia trachomatis (Group A). The prevalence of C. trachomatis infection in Group A was 2.1% (16/751). In Group B, 619 asymptomatic adolescent females attending a youth and a family planning clinic were screened for C. trachomatis by testing FCU and cervical specimens. An enzyme immunoassay (IDEIA-III) was used to detect C. trachomatis verified by fluorescein isothiocyanate-conjugated (FITC) monoclonal antibodies. Only samples positive in both tests were regarded as true positive. The cervical samples from the women in Group B were positive in 7.8% (48/619), while the FCU were positive in 6.0% (37/619). Detection of C. trachomatis by EIA in FCU samples was found useful for screening females for genital chlamydial infection. The prevalence of C. trachomatis in an unselected asymptomatic population was found to be lower than in age-matched individuals seeking medical advice in the same coherent area.

Gonococcal urethritis diagnosed from enzyme immunoassay of urine sediment.

First-catch urine specimens were obtained before clinical examination from 101 sexually active men who attended a sexually transmitted diseases clinic with a complaint of urethral discharge. Urethral swab specimens were used for preparation of smears and were then cultured on Martin-Lewis medium. Enzyme immunoassay (EIA) tests were performed on (1) uncentrifuged urine, (2) urine sediment, and (3) urine sediment diluted 1:6 with detergent buffer. Urethral cultures from 65 (64%) of the 101 men were positive for N. gonorrhoeae. EIA performed on urine sediment diluted 1:6 yielded the highest sensitivity: 98.5% (64/65). Sensitivity of EIA for uncentrifuged urine was only 66% (43/65). Specificity of all samples tested exceeded 97.2%. Overall agreement between results of EIA on diluted urine sediment and culture was 98% (99/101). Discordant culture and EIA results were unrelated to urine volume, time since prior urination, quantity of gonococcal growth on Martin-Lewis medium, duration of urine storage (less than 72 hours) before testing, or immunotype. EIA tests using urine sediment are highly sensitive and specific, and they offer an alternative means of diagnosing gonorrhea in men who refuse urethral manipulation. They also provide a means of screening men at high risk for gonorrhea who have submitted a urine specimen for other reasons.

Dipstick Leukocyte Esterase Activity in First-Catch Urine Specimens

Although sexually active female adolescents are often routinely screened for sexually transmitted diseases, indications for culturing adolescent males for sexually transmitted urethral infections are controversial. A study of 54 sexually active males (14 to 22 years old) was undertaken to assess the reliability of using dipstick leukocyte esterase activity in first-catch urine specimens to detect urethritis caused by Neisseria gonorrhoeae and Chlamydia trachomatis. Eighteen males had sexually transmitted diseases: N gonorrhoeae (nine patients), C trachomatis (eight patients), and N gonorrhoeae and C trachomatis (one patient). First-catch urine specimens with a 1+ (mild) or 2+ (moderate) reaction on dipstick testing had a leukocyte (WBC) count of 10 WBCs per high-power field or greater on microscopic analysis, with an 83% sensitivity, 100% specificity, a 100% positive predictive value, and a 92% negative predictive value for the presence of N gonorrhoeae, C trachomatis, or both. Clinical criteria for screening (urethral discharge, dysuria, or exposure to a sexually transmitted infection) plus a dipstick-positive first-catch urine specimen had a 94% sensitivity, 89% specificity, an 81% positive predictive value, and a 97% negative predictive value.

Dipstick leukocyte esterase activity in first-catch urine specimens. A useful screening test for detecting sexually transmitted disease in the adolescent male

Dipstick leukocyte esterase activity in first-catch urine specimens. A useful screening test for detecting sexually transmitted disease in the adolescent male