Characterisation of Chlamydia trachomatis by ompA sequencing and multilocus sequence typing in a Swedish county before and after identification of the new variant
2010 (English)In: Sexually Transmitted Infections, ISSN 1368-4973, E-ISSN 1472-3263, Vol. 86, no 1, 56-60 p.Article in journal (Refereed) Published
OBJECTIVES: In 2006 a new variant of Chlamydia trachomatis (nvCT), with a deletion in the cryptic plasmid, was reported in Sweden. This deletion included the targets for the genetic diagnostic systems used in many clinical laboratories and resulted in thousands of false-negative results. The aim of this study was to characterise consecutive Chlamydia tissue culture-positive samples from 2006 in Orebro County, after identification of the nvCT, and to compare the results from samples collected in the same county in 1999-2000. The study also aimed to evaluate the discriminatory capacity of multilocus sequence typing (MLST) compared with ompA sequencing. METHODS: ompA sequencing and MLST was used to characterise 100 consecutive Chlamydia tissue culture-positive samples. RESULTS: A significant (p<0.001) increase of genotype E, from 47% in 1999-2000 to 69% in 2006, was detected. All 41 nvCT isolates from 2006 displayed an identical ompA genotype E and MLST profile. Excluding the nvCT isolates, the distribution of ompA genotypes is similar to the genotyping results from 1999-2000. Among the wild-type genotype E isolates from 2006, 14 unique MLST sequence types were obtained from 26 isolates while they were identical in ompA genotyping. The discriminatory power (D) of C trachomatis strains in this material was 83.5% using the MLST system compared with 49.5% utilising ompA sequencing. CONCLUSION: In all, MLST enables improved studies of the molecular epidemiology of C trachomatis. All nvCT isolates from 2006 displayed an identical ompA genotype E and MLST profile, which strongly indicates a clonal spread of the nvCT.
Place, publisher, year, edition, pages
2010. Vol. 86, no 1, 56-60 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-125330DOI: 10.1136/sti.2009.037572ISI: 000274525800014PubMedID: 19837730OAI: oai:DiVA.org:uu-125330DiVA: diva2:319402