From the Guidelines
The most appropriate test for detecting Chlamydia trachomatis and Neisseria gonorrhoeae is a nucleic acid amplification test (NAAT) with a nasopharyngeal probe, as it offers high sensitivity and specificity for identifying these pathogens in the nasopharynx. This recommendation is based on the U.S. Preventive Services Task Force's guidelines, which suggest using NAATs for diagnosing Chlamydia trachomatis and Neisseria gonorrhoeae infections 1. The use of NAATs is supported due to their high sensitivity and specificity, and they are cleared by the U.S. Food and Drug Administration for use on various specimens, including urine and clinician-collected swabs.
Key points to consider when using this test include:
- The test can detect infections in non-genital sites, such as the throat, which is important for diagnosing asymptomatic cases.
- The nasopharyngeal probe allows for the collection of a sample from the back of the throat/nose area, which is then analyzed using nucleic acid amplification technology.
- Results are typically available within 1-3 days, allowing for prompt diagnosis and treatment.
- The test is crucial for guiding appropriate antibiotic therapy and preventing serious complications that can arise from untreated infections.
The U.S. Preventive Services Task Force's guidelines emphasize the importance of considering risk factors, such as age, sexual history, and community prevalence, when deciding who to screen for Chlamydia trachomatis and Neisseria gonorrhoeae 1. By using a NAAT with a nasopharyngeal probe, healthcare providers can effectively diagnose and manage these infections, reducing the risk of morbidity, mortality, and improving quality of life for affected individuals.
From the Research
Chlamydia Trachomatis and Neisseria Gonorrhoeae Detection
- The test for Chlamydia trachomatis and Neisseria gonorrhoeae is typically done using nucleic acid amplification tests (NAATs) 2, 3, 4, 5, 6.
- NAATs are preferred due to their high sensitivity and specificity, and can be used on specimens obtained noninvasively, such as urine samples 2, 3, 4.
- The performance of NAATs is better than that of other tests available for the diagnosis of chlamydial and gonococcal infections 3.
- NAATs that have been cleared by the Food and Drug Administration (FDA) for the detection of C. trachomatis and N. gonorrhoeae infections are recommended as screening or diagnostic tests 3.
Specimen Types
- Urine samples can be used for NAATs to detect C. trachomatis and N. gonorrhoeae, with high sensitivity and specificity 4, 5, 6.
- Endocervical swab specimens can also be used for NAATs to detect C. trachomatis and N. gonorrhoeae 5, 6.
- Liquid Pap smear medium (PreservCyt) can be used for the detection of C. trachomatis and N. gonorrhoeae, with high agreement between LCR performed on PreservCyt and LCR performed on a cervical specimen 6.
Test Characteristics
- The pooled study specificities of NAATs exceeded 97% when urine samples were tested, for both chlamydial infection and gonorrhea 4.
- The sensitivities of NAATs varied according to the type of assay, with polymerase chain reaction (PCR) and transcription-mediated amplification (TMA) having higher sensitivities than strand displacement amplification (SDA) 4, 5.
- The specificities of NAATs were high, with most studies reporting specificities above 98% 4, 5, 6.