transmitted infections (STIs), a common cause of dysuria in adolescents ( Figs 57.1 and 57.2 ) Urethral or vaginal discharge suggests an infection of the genitalia: urethritis in the boy and urethritis or vulvovaginitis in the girl (see Table 57.3 ) To evaluate the cause of discharge when there is concern for STI in prepubertal children, noninvasive methods of testing should be considered Nucleic acid amplification tests (NAATs), which use ligase chain reaction (LCR) or polymerase chain reaction (PCR) technologies, can be performed on first-catch urine (not clean-catch) to test for the presence of Chlamydia trachomatis and Neisseria gonorrhoeae in a noninvasive manner They may also be used to test for the presence of Trichomonas vaginalis in both males and females NAATs are considered the gold standard in STI testing for postpubertal patients These tests may be considered an accurate screening tool for STIs and not require obtaining cervical or male urethral swabs Self-collected vaginal swabs from adolescent female patients can also be used for testing and offer similar accuracy when compared with providerobtained cervical specimens In cases of suspected abuse, a urethral or vaginal culture may be required by local law enforcement agencies as all not accept NAAT testing Treat postpubertal patients in the ED; treatment in young children is based on presence of symptoms and clinical findings after all needed testing has been collected for medical–legal documentation For recommended treatment regimens, see Chapter 92 Gynecology Emergencies