Objectives Lymphogranuloma venereum (LGV) infections caused by Chlamydia trachomatis L serovars have emerged in 2003 in Europe among HIV-positive men having sex with men (MSM). Our aim was to evaluate LGV prevalence and predictors in a high-risk population attending to two STI clinics in the southwest of Spain between December 2013 and April 2015.

Methods Screening of C. trachomatis using commercial kits was carried out, followed by real-time pmpH-PCR discriminating LGV strains, and finally ompA gene was sequenced for phylogenetic reconstruction.

Results A total of 6398 samples were tested, of which, 594 (9.3%) were C. trachomatis-positive specimens and successfully typed by pmpH PCR. Five hundred and eighty-one samples contained non-LGV and 13 (2.2%; 95% CI 1.3% to 3.7%) samples had LGV. One hundred and sixty-six (27.9%; 95% CI 24.5% to 31.7%) CT-positive results were found in MSM. All C. trachomatis LGV types were found in rectal samples from MSM (13/166, 7.8%; 95% CI 4.5% to 13.0%). Of these, five (38.5%; 95% CI 17.7% to 64.5%) patients were asymptomatic and 11 (84.6%; 95% CI 57.8% to 95.7%; p<0.001) were also HIV positive. Successful treatment of LGV was achieved in all patients including 11/13 (84.6%) who received single-dose azithromycin. All of the L types were confirmed to be genotype L2b with ompA PCR and sequencing.

Conclusions This analysis shows that LGV infections are occurring in MSM in southwest Spain, where no data about LGV have been described before, reinforcing the need for screening and genotyping for LGV. LGV should be taken into account when considering treatment and management of rectal C. trachomatis infections, including in asymptomatic HIV-positive MSM. Larger studies on appropriate treatment for asymptomatic LGV infection are needed.