Chlamydia Testing in Sexually Active Teenagers
All sexually active adolescents under 20 years of age should be screened annually for chlamydia using nucleic acid amplification tests (NAATs), with testing repeated every time they undergo a pelvic examination unless they have been in a single, mutually monogamous relationship since their last test. 1
Screening Method and Specimen Collection
NAATs are the preferred diagnostic method for chlamydia detection in teenagers, offering 86-100% sensitivity and 97-100% specificity, significantly outperforming culture-based methods. 2
For adolescent females, the preferred specimen is a vaginal swab (which can be self-collected), with endocervical swabs or urine as acceptable alternatives. 1, 2
For adolescent males, a first-catch urine specimen is the standard collection method, providing comparable accuracy to urethral swabs with better patient acceptability. 2
Site-specific testing is mandatory based on sexual practices: rectal swabs for those engaging in receptive anal intercourse and pharyngeal swabs for gonorrhea (not chlamydia) for those engaging in receptive oral sex. 1, 2
Screening Frequency Algorithm
Standard-Risk Teenagers:
- Females under 20 years: Screen at every pelvic examination unless sexual activity has been limited to a single, mutually monogamous partner since the last test. 3
- All teenagers under 20: Screen at minimum annually regardless of reported risk behaviors. 1
High-Risk Teenagers (increase to every 3-6 months):
- Multiple or anonymous sexual partners 1
- New sexual partner within the past 3 months 3
- Inconsistent or no barrier contraception use 3
- Sex in conjunction with illicit drug use 1, 2
- History of previous STIs 1
- Sex work or exchanging sex for money/drugs 1
- Partners who engage in high-risk behaviors 1
Treatment Regimen
Azithromycin or doxycycline are the recommended first-line antibiotics for uncomplicated chlamydial infection in adolescents. 4
Immediate empiric treatment should be provided without waiting for test results when clinical suspicion is high, as follow-up compliance is often poor in this age group. 2
Partner Management
All sexual partners within the preceding 60 days must be evaluated and treated, even if asymptomatic. 2
Treatment of sex partners is critical because it represents the principal way to eliminate asymptomatic infection among males and prevents reinfection of the index patient. 3
If partners are not treated, reinfection will occur, undermining the effectiveness of treating the index patient. 3
Expedited partner therapy may be appropriate depending on local regulations, where partners receive the same treatment regimen without requiring an office visit. 2
Post-Treatment Rescreening
Mandatory rescreening at 3 months after treatment for all adolescents diagnosed with chlamydia, regardless of whether their partner was treated, due to reinfection rates as high as 39% in this population. 3, 1
If 3-month rescreening is not feasible, retest at the next healthcare visit within 12 months. 1
This rescreening is essential because reinfection occurs rapidly—within 3.6 months for chlamydia in 25% of previously infected individuals. 2
Critical Pitfalls to Avoid
Do not rely solely on urine specimens in adolescents engaging in oral or anal sex; site-specific testing is required to detect pharyngeal and rectal infections, which are frequently asymptomatic. 2
Do not accept a single annual screen for teenagers with ongoing high-risk behaviors; a 3-6 month interval is required to detect incident infections promptly. 1, 2
Do not skip the 3-month post-treatment retest—this is when the highest reinfection rates occur, and only 10% of adolescents receive this recommended retesting in real-world practice. 5
Do not assume asymptomatic means uninfected—up to 70% of chlamydial infections in adolescent females are asymptomatic, making routine screening essential rather than symptom-based testing. 6
Concurrent Testing and Counseling
Screen simultaneously for gonorrhea using the same NAAT specimen, as co-infection is common and both infections share similar risk factors. 1, 7
Test for other STIs including syphilis, HIV, and trichomonas (in females with high-risk behaviors) at the time of chlamydia screening. 1, 2
Provide safer-sex counseling at every encounter, addressing condom use, limiting number of partners, and avoiding partners at increased risk for STDs—though only 79% of adolescents receive this counseling in practice. 5
Address partner management at the initial visit, as only 52% of adolescents receive appropriate partner management counseling in real-world settings. 5