P1-S1.34 First report of the Swedish new variant ofChlamydia trachomatis(nvCT) in Russia
Authors: Shipitsyna E , Unemo M , Hadad R , Ryzhkova O , Savicheva A , Domeika M 
Published: July 2011

Background

The new variant ofChlamydia trachomatis(nvCT), first reported in Sweden in late 2006, has so far rarely been reported outside the Nordic countries. However, knowledge of the presence of nvCT beyond these countries is limited due to the few recent studies, many laboratories still cannot detect nvCT, and the ones that can detect nvCT do mainly not distinguish it from wild type CT. The aims were to i) investigate the presence of nvCT in St. Petersburg, the largest city of the Northwest of Russia and in close proximity to Sweden, and ii) assess nucleic acid amplification tests (NAATs) used in Russia to diagnoseC trachomatisinfections for their ability to identify nvCT.

Methods

June–December 2010, consecutive samples (cervical swabs from females and urethral swabs from males) found positive forC trachomatisduring routine testing with commercial PCR assays able to detect nvCT were collected. For nvCT detection, DNA was isolated using NucliSens easyMAG (bioMérieux) or QIAamp DNA mini kit (Qiagen), and analysed with an international real-time nvCT-specific PCR.C trachomatisNAATs currently used in Russia was also examined regarding their ability to detect nvCT DNA.

Results

During the study period, 9517 samples were submitted from patients of gynaecological, urological and STI clinics forC trachomatistesting. Of these samples, 275 (2.9%) from 198 females and 75 males were positive forC trachomatis. The mean age of the patients was 26.4 years (range 19–51 years). nvCT was detected in one sample (0.4%), which was obtained from a 23-year-old Russian woman. Genotyping using variable number of tandem repeats (VNTR) typing showed that the nvCT was indistinguishable to the previously typed nvCT samples from the Nordic countries (type 8.7.1). Six NAATs, which are used in the majority of laboratories in Russia performingC trachomatisdiagnostics, were assessed for the ability to detect nvCT (Abstract P1-S1.34 table 1). All evaluated assays, with exception of the Lytech PCR, tested positive with nvCT DNA. Conclusions This study is the first report of an nvCT case in Russia, and in general in Eastern Europe, and that evaluates mostC trachomatisNAATs currently used in Russia for the ability to detect nvCT. Although the prevalence of nvCT is still considered low outside Northern Europe, wider geographic spread of nvCT cannot be excluded, and therefore regular monitoring and participation in external quality assessments of diagnostic methods in use are necessary.

Abstract P1-S1.34 Table 1

Nucleic acid amplification tests (NAATs) developed and used in Russia for the detection ofChlamydia trachomatisand their ability to detect nvCT

NAAT (Manufacturer, City)Gene target(s)Able to detect nvCT?Conventional PCR (DNA-Technology, Moscow)Cryptic plasmidYesReal-time PCR (DNA-Technology, Moscow)16S rRNA geneYesConventional PCR (Central Research Institute of Epidemiology, Moscow)Cryptic plasmidYesReal-time PCR (Central Research Institute of Epidemiology, Moscow)Cryptic plasmidYesConventional PCR (Lytech, Moscow)Cryptic plasmidNoReal-time PCR (Vector-Best, Novosibirsk)Cryptic plasmid andgyrAgeneYes