First-catch Urine Research Articles

Screening for Asymptomatic Gonorrhea in Males: a Comparison of Four Techniques

A total of 729 asymptomatic men were screened for gonococcal urethritis with four techniques: culture of urethral specimens, culture of first-catch urine sediment (FCUS), an enzyme immunoassay method (Gonozyme, Abbot Laboratories) for detection of gonococcal antigen in urethral specimens (EIA-Sb) and first-catch urine sediment (EIA-FCUS). The positivity rates of the aforementioned techniques were 0.13%, 0%, 2.33%, and 0.82%. In view of reduction of time and patients' discomfort as well as the closely comparable positivity rate (p less than 0.05) associated with the use of the EIA-FCUS technique, the latter method appears to be the simplest, most practical and reliable diagnostic tool for screening asymptomatic gonococcal urethritis.

Urinary Leukocyte Esterase Screening Test for Asymptomatic Chlamydial and Gonococcal Infections in Males

We evaluated the ability of the urinary leukocyte esterase test to predict culture-verified chlamydial and gonococcal urethritis among asymptomatic adolescent males. Nine hundred forty-eight sexually active males provided first-catch urine samples for esterase screening, and 76 (8%) tested positive (greater than or equal to 1+). Among 435 boys who agreed to undergo urethral culture, the esterase was positive in 66 (15%), Chlamydia trachomatis was isolated from 39 (9%), and Neisseria gonorrhoeae was isolated from 14 (3%). The sensitivity, specificity, and positive and negative predictive values for the esterase test were 72%, 93%, and 58% and 96%, respectively. Using the esterase test to screen asymptomatic males for urethritis, we identified 38 culture-verified infections that otherwise would have remained undetected. The urinary leukocyte esterase test is a noninvasive and cost-effective screening method to detect urethritis among asymptomatic adolescent males.

Diagnosing Chlamydia trachomatis urethritis by first-catch urine enzyme immunoassay in adolescent males

This study evaluates a first-catch urine sediment enzyme immunoassay (EIA) to diagnose Chlamydia trachomatis urethritis in symptomatic adolescent males. Seven of 23 patients evaluated were diagnosed with sexually transmitted urethritis, five caused by C. trachomatis. First-catch urine sediment was accurate in diagnosing C. trachomatis urethritis when compared to urethral swab EIA ( p < 0.003). First-catch urine pyuria was also highly correlated with urethritis ( p < 0.05). First-catch urine testing is a simple, nonpainful method of screening adolescent males for urethritis, and first-catch urine sediment EIA for C. trachomatis is a rapid, painless method of diagnosis. A method for screening and diagnosis with these techniques is described.

Use of a leukocyte esterase dipstick to detect Chlamydia trachomatis and Neisseria gonorrhoeae urethritis in asymptomatic adolescent male detainees.

We tested 91 asymptomatic adolescent male detainees in a short-stay detention facility in Seattle, Washington for the presence of leukocyte esterase in first-catch urine and for Chlamydia trachomatis and Neisseria gonorrhoeae infection. C. trachomatis was isolated from 10 subjects (11 per cent) and N. gonorrhoeae from five (5 per cent). Dipsticks detected leukocyte esterase in the urine of all 15 subjects with either infection and of 13 subjects with neither infection. Detection of leukocyte esterase was 100 per cent sensitive, 83 per cent specific, and 54 per cent predictive for the presence of either organism.

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.

Asymptomatic Chlamydia trachomatis infections in teenage males

This study examined the prevalence of Chlamydia trachomatis infections of the urethra in asymptomatic teenage males in a juvenile detention setting. Gonorrhea cultures, chlamydia smears using the direct immunofluorescent antibody (DFA) technique, and 15–20 ml of a first-catch urine (FCU) sample were obtained. Of the 227 adolescent males screened, 205 had experienced sexual intercourse. Twenty-seven (13.2%) of the sexually active adolescents had positive DFA smears for C. trachomatis. Three (1.5%) had positive Neisseria gonorrhoeae cultures. A urine leukocyte count of greater than 10 per high-power field gave a 91% specificity but only a 26% sensitivity for a positive DFA. The high prevalence of chlamydia in this population and the relative low cost of the DFA screen for chlamydia make this a useful procedure for discovering unsuspected disease, particularly in a high-risk population. The FCU screen for leukocytec was of limited value in identifying asymptomatic infection.

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

Detection of Leukocyte Esterase in Urine

First-catch urine samples of 130 men attending a clinic for genitourinary medicine were screened with the leukocyte esterase dipstick test. Conventional microscopy of centrifuged sediment and inverted microscopy of unspun urine samples were performed 2-4 hr later. The leukocyte esterase test had sensitivities of 100% and 96.6% and specificities of 55% and 52.8%, respectively, when compared with the two microscopic methods. The apparently low predictive value of the positive leukocyte esterase test was probably linked to its ability to detect lysed cells and the limitations of the microscopic methods, which were used as the absolute indicator of nongonococcal urethritis. Of the 42 patients with microscopic pyuria, 45.2% had positive cultures for Chlamydia trachomatis, and the leukocyte esterase test was positive in every case. Twenty-one per cent of the C. trachomatis-positive patients were asymptomatic, and 42% had fewer than five polymorphonuclear leukocytes per high-power field (X1000) of the gram-stained urethral smear. The leukocyte esterase test appears to be a simple, practical, and sensitive test that is useful in screening for nongonococcal urethritis, especially asymptomatic nongonococcal urethritis.

SCREENING FOR CHLAMYDIA TRACHOMATIS AND NEISSERIA GONORRHOEAE IN ADOLESCENT MALES: VALUE OF FIRST-CATCH URINE EXAMINATION

50 adolescent males attending a general teen clinic (aged 13-21) were evaluated for urethritis. After examination of sediment from the initial 15-20 ml of voided urine, first-catch urine (FCU), specimen urethral swabs were taken for culture of Chlamydia trachomatis and Neisseria gonorrhoeae. 21 of 23 (91%) males with >10 leucocytes per high-power field of resuspended sediment (FCU-positive) had positive urethral cultures for C trachomatis or N gonorrhoeae compared with only 1 of 27 (4%) FCU-negative subjects (p<0·001) 12 of 22 culture-positive subjects had no genitourinary symptoms and 11 of the 12 had C trachomatis infections. The sensitivity of FCU examination in identifying culture-positive urethritis was 95%, the specificity 93%, and the predictive value of a positive FCU 91%. FCU examination is a useful, non-invasive screening test to detect urethritis associated with C trachomatis and N gonorrhoeae. The test may be especially helpful in identifying symptom-free males with chlamydia-associated urethritis.