Chlamydia trachomatis infections
Rates of chlamydia infection have doubled in the last decade. Adherence to screening guidelines for the infection is important for identifying cases, initiating treatment, and reducing maternal and neonatal morbidity
Treatment options
Prompt treatment of C trachomatis infection is essential to decrease the risk of disease sequelae. Nonpregnant adults can be treated with oral doxycycline 100 mg twice daily for 7 days.
In a head-to-head study performed in a controlled environment that ensured treatment adherence, 97% efficacy was achieved with one oral dose of azithromycin (1 g) compared with 100% efficacy with doxycycline.10 However, in the real-world setting, imperfect adherence to the multi-day doxycycline regimen is associated with treatment failures. Thus, a single dose of azithromycin is preferable for patients with questionable compliance.11
In obstetric patients, azithromycin and amoxicillin are preferred as first-line agents for treatment of C trachomatis due to their improved safety profile in this demographic. Amoxicillin 500 mg orally 3 times daily for 7 days has 95% efficacy.2
Women allergic to these agents may be treated with an alternative regimen of erythromycin base, 500 mg orally 4 times daily for 7 days, or erythromycin ethylsuccinate, 800 mg orally 4 times daily for 7 days. Erythromycin should be reserved for second-line therapy because of its lower efficacy (64%) and frequent gastrointestinal adverse effects.2 Doxycycline is contraindicated in pregnancy because of possible teratogenic effects on the teeth and bone of the fetus.
