Genotyping of Chlamydia trachomatis in rectal and pharyngeal specimens: identification of LGV genotypes in Finland
- 1Department of Virology, Haartman Institute, University of Helsinki, Helsinki, Finland
- 2Clinic of Venereal Diseases, Skin and Allergy Hospital, Helsinki University Central Hospital, Helsinki, Finland
- 3Department of Infectious Disease Surveillance and Control, National Institute of Health and Welfare, Helsinki, Finland
- 4Department of Virology and Immunology, Helsinki University Central Hospital, Laboratory Division (HUSLAB), Helsinki, Finland
- Correspondence to Dr Mirja Puolakkainen, Department of Virology, Haartman Institute, P.O. Box 21, University of Helsinki, Helsinki, FIN-00014, Finland;
Contributors SK performed the laboratory testing and drafted the manuscript, EH-B collected data and samples and read the manuscript and MP supervised the study and finalized the manuscript. All authors contributed to and approved the final version of the manuscript.
- Accepted 25 March 2012
- Published Online First 19 April 2012
Objectives Lymphogranuloma venereum (LGV) infections caused by Chlamydia trachomatis L types have recently emerged in Europe among HIV-positive men having sex with men. Our aim was to introduce a genotyping strategy suitable for a diagnostic laboratory using nucleic acid amplification tests (NAATs) for detection of C trachomatis and to investigate the prevalence of LGV types in rectal and pharyngeal specimens in Finland.
Methods Aptima Combo 2 (Gen-Probe) was used to detect C trachomatis in swabs. Altogether 140 C trachomatis NAAT-positive rectal and pharyngeal samples were genotyped by pmpH and ompA real-time PCR.
Results Of the 140 NAAT-positive rectal and pharyngeal specimens, 114 (81%) were successfully typed by pmpH PCR. One hundred and four samples contained non-LGV, nine samples LGV and one sample both non-LGV and LGV C trachomatis types. The C trachomatis LGV types were mainly found in rectal samples. Six of the L types were confirmed to be genotype L2b and two were L2 with ompA PCR and sequencing.
Conclusions Our experience suggests that genotyping C trachomatis by pmpH PCR can be introduced as a function of a diagnostic laboratory already using NAAT for detection of C trachomatis. The data show that LGV infections occur also in Finland. LGV should be taken into account when considering treatment and management of rectal C trachomatis infections.
- Chlamydia trachomatis infections
- lymphogranuloma venereum
- chlamydia infection
- molecular epidemiology
Presented in part: 12th International Symposium on Human Chlamydial Infections, Hof bei Salzburg, Austria, June 2010 (abstract pp. 405–408).
Funding This study was supported by an R&D grant from Helsinki University Central Hospital, Laboratory Division (HUSLAB), MLE82TK013, by The Finnish Society against Sexually Transmitted Diseases and by the Academy of Finland in the frame of the ERA-NET PathoGenoMics, #217554/ECIBUG and #130043/ChlamyTrans.
Competing interests None.
Ethics approval The Ethics Committee, Department of Medicine at Hospital District of Helsinki and Uusimaa.
Provenance and peer review Not commissioned; externally peer reviewed.