From the Guidelines
Urine testing is highly effective for diagnosing gonorrhea and chlamydia infections, with sensitivity ranging from 86% to 100% for chlamydia and 90% to 100% for gonorrhea, as reported in a 2014 study by the U.S. Preventive Services Task Force 1. The efficacy of urine testing for gonorrhea and chlamydia is well-established, with high sensitivity and specificity for both infections.
- The sensitivity of NAAT specimens collected from genitourinary sites for detecting chlamydia ranged from 86% to 100% in studies without major limitations.
- In men, testing of urine specimens was slightly more sensitive than testing of urethral specimens.
- The sensitivity of NAATs for gonorrhea ranged from 90% to 100% in studies without major limitations.
- Specificity was high across all specimens and tests for both chlamydia and gonorrhea, as noted in the 2014 study 1. The use of urine testing for gonorrhea and chlamydia has been shown to be effective in reducing the incidence of pelvic inflammatory disease (PID) in nonpregnant women at increased risk for infection, with a relative risk reduction of 0.44 (95% CI, 0.20 to 0.90) in one large randomized controlled trial 1. It is essential to note that while urine testing is effective for diagnosis, it has no therapeutic value for treating these infections, and antibiotics are required for treatment.
- The current recommended regimen for uncomplicated gonorrhea is a single 500mg intramuscular injection of ceftriaxone.
- For chlamydia, the standard treatment is doxycycline 100mg taken orally twice daily for 7 days, or alternatively, azithromycin 1g as a single oral dose. These recommendations are based on the bacteria's susceptibility to specific antibiotics that target their cellular mechanisms, which urine cannot replicate, as reported in the 2014 study by the U.S. Preventive Services Task Force 1.
From the Research
Efficacy of Urine for Gonorrhea and Chlamydia
- The efficacy of urine for gonorrhea and chlamydia can be determined through nucleic acid amplification tests (NAATs), which are highly sensitive and specific 2, 3, 4.
- NAATs can be used to diagnose gonorrhea and chlamydia infections using self-collected urine samples, which can decrease the necessity for a clinician to perform a pelvic examination on women or to collect a urethral swab from men 2.
- The use of NAATs for self-collected urine samples can greatly increase the types and numbers of patients that can be screened outside of clinic settings, especially for asymptomatic cases 2, 3.
- Studies have shown that NAATs perform well for detection of chlamydia and gonorrhea with self-obtained vaginal swabs, but also with urine samples, with sensitivities and specificities ranging from 80% to 100% 5, 6.
- The performance of NAATs using urine specimens is similar to that of cervical and vaginal specimens for chlamydia and gonorrhea detection, with estimates ranging from 57% to 100% for chlamydia and 67% to 94% for gonorrhea 6.
Comparison with Other Specimens
- Vaginal specimens have been shown to have similar performance to cervical and urine specimens for chlamydia and gonorrhea detection 6.
- Urine specimens have been estimated to have a performance >80% for chlamydia and gonorrhea infections in most studies 6.
- The use of urine specimens for NAATs can provide a suitable alternative to traditionally used specimens, with higher acceptability and lower cost 6.
Clinical Implications
- The use of NAATs for self-collected urine samples can extend the diagnostic capability for detecting gonorrhea and chlamydia infections to nonclinic screening venues 2.
- Clinicians can easily screen patients in the clinic for STIs who are not presenting for pelvic or urogenital examinations using NAATs with urine samples 2.
- Automated, cartridge-based NAATs can be considered for routine use in diagnosing those at risk for STIs, including gonorrhea and chlamydia 3.