High-resolution genotyping of Lymphogranuloma Venereum (LGV) strains of Chlamydia trachomatis in London using multi-locus VNTR analysis-ompA genotyping (MLVA-ompA)

Background Lymphogranuloma venereum (LGV) is caused by Chlamydia trachomatis strains with ompA genotypes L1 to L3. An LGV epidemic associated the L2b genotype has emerged in past few decades amongst men who have sex (MSM). C . can be discriminated outer membrane protein A gene ( ) sequencing, however this method limited resolution. This study employed a high-resolution genotyping method, namely, multi-locus tandem repeat (VNTR) analysis sequencing (MLVA- ), assess distribution of MLVA- individuals attending genitourinary medicine (GUM) clinics London. Methods Clinical specimens were collected from eight London-based GUM clinics. Specimens that tested positive for commercial nucleic acid amplification test (NAAT) confirmed as pmpH real-time PCR. LGV-positive DNA extracts subsequently genotyped using Results Two hundred and thirty LGV, 162 (70%) yielded complete genotypes. Six identified: 1.9.2b-L2, 1.9.3b-L2b, 1.9.2b-L2b, 1.9.2b-L2b/D, 1.4a.2b-L2b, 5.9.2b-L1. The following identified (in descending order abundance): L2, L2b, L2b/D, L1. Eight sequences hybrid L2b/D profile detected. sequence was identical recombinant strain detected Portugal 2017. Conclusions L2 found predominate London population. an unusual previously reported Portugal. We recommend further monitoring surveillance within UK