A young female presented with vaginal discharge. Endocervical biopsy revealed chlamydial antigen. Treatment given should be
**Core Concept**
Chlamydia trachomatis is a sexually transmitted bacterium that causes cervicitis, characterized by mucopurulent endocervical discharge. The organism is an obligate intracellular pathogen that requires specific antibiotics for effective treatment.
**Why the Correct Answer is Right**
Chlamydia trachomatis is typically treated with antibiotics that target intracellular pathogens, such as azithromycin or doxycycline. Azithromycin is a macrolide antibiotic that inhibits protein synthesis in bacteria by binding to the 50S ribosomal subunit, thereby preventing the formation of the polypeptide chain. Doxycycline, on the other hand, is a tetracycline antibiotic that inhibits protein synthesis by binding to the 30S ribosomal subunit. Both azithromycin and doxycycline are effective against Chlamydia trachomatis and are recommended by the Centers for Disease Control and Prevention (CDC) for the treatment of chlamydial infections.
**Why Each Wrong Option is Incorrect**
**Option A:** Amoxicillin is a beta-lactam antibiotic that targets cell wall synthesis in bacteria. It is not effective against intracellular pathogens like Chlamydia trachomatis.
**Option B:** Ciprofloxacin is a fluoroquinolone antibiotic that targets DNA gyrase and topoisomerase IV in bacteria. While it is effective against a wide range of bacterial infections, it is not the first-line treatment for chlamydial infections.
**Option C:** Metronidazole is an antibiotic that targets anaerobic bacteria and protozoa. It is not effective against Chlamydia trachomatis.
**Clinical Pearl / High-Yield Fact**
It is essential to treat sexual partners of individuals with chlamydial infections to prevent reinfection and transmission of the disease. Additionally, repeat testing after treatment is recommended to ensure that the infection has been fully cleared.
**Correct Answer: C. Azithromycin**