**3. Chlamydial oropharyngitis–tonsillitis**

*C. trachomatis* can be transmitted after oral sex. Many patients with *C. trachomatis* in the oropharyngeal region are asymptomatic. Rarely, it can cause oropharyngitis and tonsillitis. In this case, it can lead to symptoms such as sore throat, difficulty swallowing, and fever. Swab samples taken from this region are used for diagnosis. NAATs are one of the most sensitive tests used in the examination of samples and are

#### *Chlamydia and the Gastrointestinal System DOI: http://dx.doi.org/10.5772/intechopen.110485*

recommended for use in diagnosing *C. trachomatis*. Its specificity and sensitivity are quite high [38]. Although the clinical significance of oropharyngeal *C. trachomatis* infection is unclear and oropharyngeal sampling is not routinely recommended during screening for chlamydia infection, existing evidence has shown that oropharyngeal chlamydia infection can be transmitted sexually to the genital areas [39]. Therefore, if *C. trachomatis* is detected in the oropharyngeal sample, the patient should be treated with azithromycin and doxycycline. There is not enough clinical information to compare the efficacy of antimicrobials in oropharyngeal *C. trachomatis* infection. In a double-blind randomized controlled study, no significant difference was found in terms of treatment success of urogenital *C. trachomatis* infection in men and women between the use of a delayed release 200 mg doxycycline tablet for 7 days and a 100 mg doxycycline tablet twice a day for 7 days, although gastrointestinal side effects were less in the group that received a single dose of 200 mg. On the other hand, the cost of a single-dose 200 mg tablet is higher [40].
