Urine-based screening for Chlamydia trachomatis in men attending sexually transmitted disease clinics.

BACKGROUND: Nucleic acid-amplified tests for Chlamydia trachomatis are accurate but costly. Screening strategies for asymptomatic men are needed. GOAL: To assess C trachomatis screening strategies for asymptomatic males. STUDY DESIGN: Men attending a sexually transmitted disease clinic were tested for C trachomatis with ligase chain reaction and culture, and for urethral inflammation with urine leukocyte esterase and urethral Gram stain. RESULTS: C trachomatis prevalence was 5.5% among 1,625 asymptomatic men. Ligase chain reaction increased detection by 49% among men without urethral inflammation. An age of younger than 25 years and urethral inflammation were associated with positive ligase chain reaction results. The negative predictive value of urine leukocyte esterase was highest among older men, but urethral Gram stain was equally sensitive in predicting infection regardless of age. An age of younger than 30 years or urethral inflammation identified the highest proportion of infections (92%) and reduced the percentage of men screened by 43%. CONCLUSIONS: Urine ligase chain reaction increased C trachomatis detection, particularly among men without urethral inflammation. Testing all asymptomatic men younger than 30 years is optimal, whereas negative urine leukocyte esterase or urethral Gram stain results in men 30 years or older support no testing.

Community-based urine screening for Chlamydia trachomatis with a ligase chain reaction assay.

BACKGROUND: Urine tests for Chlamydia trachomatis permit expansion of screening beyond traditional clinic environments. Prevention of infection in teenagers is a high priority. OBJECTIVE: To define the prevalence of C. trachomatis among teenagers by using the ligase chain reaction assay on urine specimens and to evaluate leukocyte esterase testing of urine specimens as an indicator of infection. DESIGN: Cross-sectional study. SETTING: An adolescent clinic, a juvenile detention facility, seven school-based clinics, and three community-based youth organizations in Seattle, Washington. PARTICIPANTS: 10,118 sexually active teenagers and young adults. MEASUREMENTS: Chlamydia trachomatis infection detected in urine specimens by ligase chain reaction assay and leukocyturia detected by leukocyte esterase testing. RESULTS: The prevalence of chlamydial infection among female participants was 8.6% and declined with increasing age; among male participants, it was 5.4% and increased with increasing age. In female participants, independent predictors of infection were being 17 years of age or younger (odds ratio [OR], 1.49), having had two or more sex partners in the previous 2 months (OR, 1.61), and having genitourinary symptoms (OR, 1.46). In male participants, independent predictors were being of nonwhite race or ethnicity (OR, 2.00 to 3.08), having had two or more sex partners in the previous 2 months (OR, 1.57), and having used a condom during the most recent sexual encounter (OR, 0.67). For identifying infection in male participants, the sensitivity of leukocyte esterase testing was 58.9%, the specificity was 94.9%, the positive predictive value was 38.4%, and the negative predictive value was 97.7%. CONCLUSIONS: Chlamydial infection is common in teenagers and young adults in community settings. The urine ligase chain reaction assay will permit widespread screening for C. trachomatis, but leukocyte esterase testing had low sensitivity for selecting persons for screening with this assay. Indicators of chlamydial infection differed substantially in male and female participants.