Clamping Down on Chlamydia


By Dave Aughey, MD, FAAP, Medical Director, Adolescent Medicine, Children’s Hospitals and Clinics of Minnesota

Chlamydia genital infections are the most commonly reported infectious diseases in Minnesota. The burden of infection is most common among sexually experienced adolescents and young adults. Substantial health disparities exist — with the prevalence among blacks more than 10 times that of whites. Chlamydia prevalence in 14-29 year olds is 2.5 times greater than in 25-39 year olds. In 2012, Greater Minnesota had the largest increase in chlamydia — more than double the rate increase in the Twin Cities. Nationally, among 14-19 year old females, chlamydia prevalence is 6.8 percent overall (4.4 percent for whites vs. 16.2 percent for blacks).

Most genital chlamydia infections in males and females are asymptomatic or have minimal, intermittent symptoms. Important sequelae include cervicitis, Bartholin abscess, epididymitis and urethritis (in both genders). In females, chlamydia can ascend to the upper genital tract resulting in pelvic inflammatory disease (PID), fallopian tube fibrosis and scarring, tubal factor infertility, ectopic pregnancy and chronic pelvic pain. Chlamydia is the leading preventable cause of infertility.

Genital chlamydia infections are readily diagnosed using nucleic acid amplification tests (NAATs). For screening, a vaginal swab (collected by the clinician or by the patient) for females, and a first-void urine specimen for males, is preferred. Though some clinics conduct urine tests for females, vaginal swab has a higher sensitivity.

The cornerstone of chlamydia prevention is regular screening. Annual screening is recommended for all sexually active females 25 years and younger. Risk factors for additional screening include recent onset of sexual activity and having a new sex partner, or more than one partner. The U.S. Preventive Services Task Force designates annual screening as an A-rated preventive service as screening has been shown to decrease the prevalence of chlamydia and PID. Despite being rated as one of the top ten most beneficial and cost-effective preventive services, it is also among the most underutilized. In Minnesota in 2009, screening rates were 43 percent among eligible females enrolled in commercial health plans and 57 percent among the Medicaid population.

Routine screening is not currently universally recommended for males but should be considered in settings with a high prevalence of chlamydia or based on sexual risk assessment (history of STDs, lack of condom use, multiple partners, other high risk behaviors).

Clinical Pearls

  • Uncomplicated genital chlamydia infections (asymptomatic patient with a positive test or cervicitis, urethritis) are treated with 1 gm of azithromycin as a single dose, or 100 mg doxycycline twice a day for 7 days. Abstinence from all sexual activities is recommended (not even with a condom) until after 7 days of completed treatment AND until 7 days after partner(s) are treated.
  • 10-15 percent of untreated Chlamydia may result in PID. Note that azithromycin is not adequate treatment for PID.
  • Reinfections, usually from untreated partners, are common. Chlamydia-infected males and females should be retested about 3 months after treatment.
  • Test-of-cure is generally not recommended. It takes about 3 weeks for chlamydia DNA/RNA to clear the genital tract after treatment. Retesting before 3 weeks may result in a false-positive result.
  • Sexual partners of those who have tested positive for Chlamydia should be treated as a “Chlamydia-Contact.” Treating the male partners of infected females is critical for preventing repeat infections in females. Treatment should occur regardless of the absence of symptoms or a negative test.
  • Persistent symptoms (dysuria, vaginal discharge or burning) or findings (cervicitis, pyuria) can be from re-infection from untreated partners (the most common cause), co-infection (trichomoniasis) or treatment failure.

Although most adolescents have heard of chlamydia, lack of adequate knowledge and misconceptions are common as is fear of getting tested. The asymptomatic nature of most chlamydia infections may discourage testing because “How can I have chlamydia if I feel fine?” and “Even so, how can it cause harm if there aren’t any symptoms?” Messages about testing need to focus on the positive dimensions of being tested (being responsible about being sexual, protecting your partner, getting early treatment).

Chlamydia conundrums
There is increasing concern about medication-related treatment failures. A recent small study in males found that azithromycin was only 77 percent effective in eradicating chlamydia versus 95 percent for doxycycline. Other studies have noted cure rates of 81-90 percent for azithromycin and 99-100 percent for doxycycline. More studies are needed, and treatment recommendations have not changed.

Limited studies on the natural history of chlamydia have noted that spontaneous resolution occurred in 18 percent of STD clinic patients in the interval between screening and returning for treatment of a positive test.

National Chlamydia Coalition:
AAP’s Chlaymydia training resources: visit AAP website
Center for Young Women’s Health:
AAP Healthy Children

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