Chlamydia trachomatis in Cervical Lymph Node of Man with Lymphogranuloma Venereum, Croatia, 20141

Rhein inhibits Chlamydia trachomatis infection by regulating pathogen-host cell

The global incidence of genital Chlamydia trachomatis infection increased rapidly as the primary available treatment of C. trachomatis infection being the use of antibiotics. However, the development of antibiotics resistant stain and other treatment failures are often observed in patients. Consequently, novel therapeutics are urgently required. Rhein is a monomer derivative of anthraquinone compounds with an anti-infection activity. This study investigated the effects of rhein on treating C. trachomatis infection. Rhein showed significant inhibitory effects on the growth of C. trachomatis in multiple serovars of C. trachomatis, including D, E, F and L1, and in various host cells, including HeLa, McCoy and Vero. Rhein could not directly inactivate C. trachomatis but could inhibit the growth of C. trachomatis by regulating pathogen-host cell interactions. Combined with azithromycin, the inhibitory effect of rehin was synergistic both in vitro and in vivo. Together these findings suggest that rhein could be developed for the treatment of C. trachomatis infections.

Substantial underdiagnosis of lymphogranuloma venereum in men who have sex with men in Europe: preliminary findings from a multicentre surveillance pilot

Objectives

Understanding the public health impact of lymphogranuloma venereum (LGV) in Europe is hampered by inadequate diagnostics and surveillance systems in many European countries. We developed and piloted LGV surveillance in three European countries without existing systems and performed a preliminary investigation of LGV epidemiology, where little evidence currently exists.

Methods

We recruited STI or dermatovenereology clinics and associated laboratories serving men who have sex with men (MSM) in Austria, Croatia and Slovenia, using the UK for comparison. We undertook centralised LGV testing of Chlamydia trachomatis (CT)-positive rectal swabs collected between October 2016 and May 2017 from MSM attending these clinics. Stored specimens from Austria (2015–2016) and Croatia (2014) were also tested. Clinical and sociodemographic data were collected using a standardised proforma. The ompA gene of LGV-positive specimens was sequenced.

Results

In total, 500 specimens from CT-positive MSM were tested, and LGV positivity was 25.6% (128/500; 95% CI 22.0% to 29.6%) overall, and 47.6% (79/166; 40.1% to 55.2%) in Austria, 20.0% (3/15; 7.1% to 45.2%) in Croatia, 16.7% (1/6; 3.0% to 56.4%) in Slovenia and 14.4% (45/313; 10.9% to 18.7 %) in the UK. Proformas were completed for cases in Croatia, Slovenia and in the UK; proformas could not be completed for Austrian cases, but limited data were available from line listings. Where recorded, 83.9% (78/93) of LGV-CT cases were HIV-positive compared with 65.4% (149/228) of non-LGV-CT cases; MSM with LGV-CT were more likely to have proctitis (Austria, 91.8% vs 40.5%, p<0.001; Croatia, 100% vs 25%, p=0.04; UK, 52.4% vs 11.7%, p<0.001) than those with non-LGV-CT. Six different ompA sequences were identified, including three new variants; the L2 ompA sequence predominated (58.6%, 51/87).

Conclusions

LGV is substantially underdiagnosed in MSM across Europe. Unified efforts are needed to overcome barriers to testing, establish effective surveillance, and optimise diagnosis, treatment and prevention.

Infections caused by Chlamydia trachomatis (including lymphogranuloma venereum) and Mycoplasma genitalium

Sexually transmitted infections caused by Chlamydia trachomatis, including lymphogranuloma venereum and Mycoplasma genitalium have increased in last decade. This epidemiological scenario presents new challenges in order to improve and strengthen our control and prevention strategies. The routine clinical diagnosis of urethritis and cervicitis must be combined with the active search for the causal agent in men with symptoms of dysuria or proctitis, and in women with pelvic inflammatory disease. We should also include sexually transmitted infections screening in asymptomatic patients with sexual risk behaviours or sexual contact with patients diagnosed with an sexually transmitted infection. The microbiological diagnosis must be based on molecular techniques capable of detecting Chlamydia trachomatis (discriminating between L genotypes associated with lymphogranuloma venereum and other genotypes) and Mycoplasma genitalium (ideally including the identification of macrolide-resistant strains). A faster and specific diagnosis will allow for a targeted treatment with a suitable antibiotic regimen. We also recommend including contact tracing of sexual partners and, occasionally, a cure test. Finally, sexually transmitted infection screening must be widely implemented in those population groups with a high prevalence of sexually transmitted infections.