Purpose: Today, many urologists use nucleic acid amplification tests (NAAT) in diagnosis of Chlamydia trachomatis infection in Korea. A new variant of C. trachomatis with a deletion in the cryptic plasmid, which cannot be detected using commercial tests targeting the deleted DNA sequences, has been found in Sweden. Therefore, the partial deletion of cryptic plasmid DNA means that the diagnostic standards cannot detect chlamydial infection any more in cases of new mutants. The mutant type has been prevalent in Sweden, however, its incidence was not high in other countries such as France, Holland, and Denmark. In or to study the existence of this mutant C. trachomatis in Korea, we developed new primer sets for detection of this mutation.

Materials and Methods: We collected the first voided urine from male urethritis patient from April 2012 to August 2013 (Dankook University Hospital, Cheonan, Korea). We used the 25 confirmed C. trachomatis-positive specimens by using KL1 and KL2 primers for C. trachomatis and tested the existence of mutant chlamydial infection with the newly developed primer sets.

Results: We could not detect any new variant in the samples.

Conclusions: Although this mutant C. trachomatis is not seen in Korea, we should watch for the occurrence of the type in the future. I would like to briefly report on implications of the surging mutant forms and how we might attain an understanding of this phenomenon.