Genital Chlamydia trachomatis infection is a urogenital system infection caused by Chlamydia trachomatis. The most commonly affected site is the cervix, followed by the urethra and the upper genital tract. This condition may lead to pelvic inflammatory disease (PID), increasing the risk of tubal infertility and ectopic pregnancy.
Related Factors for Disease Onset
Chlamydia trachomatis is a prokaryotic microorganism that acts as an intracellular parasite in eukaryotic cells. It primarily infects epithelial cells, leading to inflammation of the cervical, endometrial, and fallopian tube mucosa.
The infection rate of Chlamydia trachomatis is high among sexually active young women and is often accompanied by co-infections with other sexually transmitted pathogens such as Mycoplasma, Neisseria gonorrhoeae, and Trichomonas vaginalis.
Modes of Transmission
The primary mode of transmission is sexual contact, with indirect transmission being rare. In pregnant women, intrauterine transmission may occur. Vertical transmission is most commonly observed when the fetus passes through the infected birth canal during delivery.
Effects on Mother and Child
Chlamydia trachomatis infection during pregnancy increases the risks of premature rupture of membranes, preterm birth, and low birth weight. Neonatal infections mainly manifest as neonatal conjunctivitis or pneumonia.
Clinical Manifestations
Most infected individuals are asymptomatic or present with mild symptoms. Symptomatic cases may show an increase in vaginal discharge. Ascending infections may cause acute cervicitis, urethritis, endometritis, ectopic pregnancy, or infertility. Severe cases may lead to peritonitis or perihepatitis.
Diagnosis and Differential Diagnosis
Diagnosis is based on a combination of patient history, clinical manifestations, and laboratory tests. Laboratory tests include:
- Nucleic Acid Testing: This method has high sensitivity and specificity, though false positives may result from contamination.
- Antigen Testing: Includes direct immunofluorescence and enzyme-linked immunosorbent assay (ELISA).
- Culture Methods: Cervical swab specimens can be cultured for Chlamydia trachomatis, but clinical use is limited due to the difficulty of this method.
- Antibody Testing: Elevated IgM antibody titers for Chlamydia trachomatis in the serum are diagnostically significant in neonatal Chlamydia pneumonia.
Differentiation from Neisseria gonorrhoeae infection is required.
Treatment
Cervicitis
The recommended regimen is doxycycline 0.1 g taken orally twice daily for 7 days.
Alternative regimens include:
- Azithromycin 1 g taken orally as a single dose.
- Tetracycline 0.5 g taken 4 times daily for 7 days.
- Erythromycin 0.5 g taken 4 times daily for 7 days.
- Ofloxacin 0.3 g taken twice daily for 7 days.
Pelvic Inflammatory Disease (PID)
This can be seen in the related guidelines for detailed management.
Treatment During Pregnancy
The preferred regimen is azithromycin 1 g taken orally as a single dose.
Alternative regimens include:
- Amoxicillin 0.5 g taken 3 times daily for 7 days.
- Erythromycin 0.5 g taken 4 times daily for 7 days.
Quinolones and tetracycline antibiotics are contraindicated during pregnancy.
Newborns with potential exposure should receive timely treatment. For neonatal pneumonia, the recommended regimen is erythromycin at a dose of 50 mg/kg/day orally in 4 divided doses for 14 days. As an alternative, azithromycin 20 mg/kg/day orally for 3 days may be used. Prophylaxis of neonatal Chlamydia conjunctivitis can include erythromycin 0.5% eye ointment or tetracycline 1% eye ointment applied immediately after birth. In cases of Chlamydia conjunctivitis, 1% silver nitrate eye drops have therapeutic utility.
Follow-Up
Retesting is recommended 3 months after completing standard treatment. Retesting for Chlamydia trachomatis is also appropriate at least 4 weeks after treatment completion for pregnant individuals or those with persistent symptoms.