Chlamydia trachomatis Antibodies, IgA
Code:18003
| Includes | Chlamydia trachomatis IgA antibody |
|---|
Analysis details
Methodology
- Enzyme immunoassay (EIA)
Expected Turnaround Time
1–2 days
Special Instructions
- Avoid smoking for at least 30 minutes before the blood sample is collected.
How to use
The Chlamydia trachomatis Antibodies, IgA test (anti–Chlamydia trachomatis IgA) assists with diagnosis and staging of urogenital chlamydial infection by documenting a mucosal IgA response. Results can inform decisions about initiating antimicrobial therapy and are used to monitor response to antibiotic treatment. In pregnancy, C. trachomatis IgA serology may help assess the risk of vertical transmission when maternal genital tract inflammation is suspected. Serology can be employed adjunctively with direct detection methods in infertility evaluations and in selected neonatal presentations.
Limitations
Chlamydia trachomatis is an obligate intracellular bacterium that targets mucosal epithelial cells of the urogenital tract, rectum, oropharynx, and conjunctiva. Perinatal spread to the neonatal eyes and respiratory tract may occur during delivery. The organism alternates between a small, extracellular elementary body that is relatively antibiotic-insensitive and an intracellular, replicating reticulate body; this biphasic cycle contributes to persistence and recurrent disease. In women, infection commonly manifests as cervicitis and can ascend to involve the endometrium and fallopian tubes, resulting in salpingitis with potential sequelae of tubal occlusion, ectopic pregnancy, and infertility. In men, typical presentations include urethritis and epididymitis, with prostatitis reported less frequently. Among pregnant individuals, cervical infection is reported in 5% to 20%, and approximately half of exposed neonates become infected during delivery; neonatal conjunctivitis is common, and about 10% develop pneumonia. Humoral responses include IgM, IgA, and IgG. C. trachomatis–specific IgA appears about 10–15 days after a primary infection, correlates with active mucosal infection or exacerbation of chronic disease, and usually declines as infection resolves, though persistence may be seen in chronic infection. Interpretation of C. trachomatis IgA results should be integrated with clinical findings and, when appropriate, with direct detection testing.
| Reference interval | — |
|---|---|
| Indications | Symptoms consistent with urogenital chlamydia, such as cervicitis with vaginal discharge, dysuria, or pelvic pain, Nongonococcal urethritis in men with urethral discharge and dysuria, Infertility evaluation in females or males, Suspected neonatal conjunctivitis or pneumonia, Determining the stage of chlamydial infection, Monitoring response to antimicrobial therapy, Pregnancy with suspected infection of the genital or urinary tract |
Possible Causes of Abnormal Results
Decreased levels
- early infection (<2 weeks from onset)
Specimen Requirements
| Specimen | Rapid PCR specimen |
|---|---|
| Container | Rapid Test Cartridge / Swab |
References
Black C.M. Current methods of laboratory diagnosis of Chlamydia trachomatis infections // Clin. Microbiol. Rev. – 1997. – № 10. – стр. 160-184.
Black C.M. Serological tests for Chlamydia trachomatis infections (Author’s Reply) // Clin. Microbiol. Rev. – 1998. – № 11. – P. 228-229.
Centers for Disease Control and Prevention. Recommendations for the prevention and management of Chlamydia trachomatis infections // Morbidity and Mortality Weekly Report. – 1993. – № 42. – RR-12. – P. 1–39.
Ishi K., Shimota H., Kawashima T., Kawahata S., Kubota T., Takada M. Significance of determination of the blood antibody level in Chlamydia trachomatis infection of the uterine cervix // Rinsho Byori. – 1991. – № 39. – P. 1215-1219.
Numazaki K. Serological tests for Chlamydia trachomatis infections (Letter to the Editor) // Clin. Microbiol. Rev. – 1998. – № 11. – P. 228.
Takaba H., Nakano Y., Miyake K. Studies on detection of serum IgA and IgG antibodies specific for Chlamydia trachomatis in latent infections in males // Nippon Hinyokika Gakkai Zasshi. – 1991. – № 82. – P. 1084-1090.
Workowski K.A., Lampe M.F., Wong K.G., Watts M.B., Stamm W.E. Long-term eradication of Chlamydia trachomatis genital infection after antimicrobial therapy. Evidence against persistent infection // JAMA. – 1993. – № 270. – P. 2071–2075.