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 greater than 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 less than 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, noninvasive 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.