European Guidelines on Chlamydia control recommend that the diagnosis of LGV is based on clinical suspicion, epidemiologic information and differential diagnosis for procto-colitis, inguinal lymphadenopathy, or genital or rectal ulcers [10].
In our experience, the cases observed in the heterosexual individuals presented with the classic clinical manifestation, i.e., ano-genital ulcerative lesions and lymphadenopathy. Differently, the cases observed in the last 2 years, all occurring in HIV-infected MSM, presented with rectal symptoms. It is important to emphasize that during the period 2010–2014, no cases of LGV have been observed in our STI center, which is the largest in Rome. On the one hand, the complete absence of diagnoses in this time period might be due to the fact that many diagnoses have been missed because of a low awareness of the clinicians for this disease, which is rare in EU. On the other hand, this fact seems to suggest an epidemiological distance between the two clinically different series of cases, and a recent circulation of CT L2b serovar among MSM living in Rome.
Scarce data are available in Italy on the burden of LGV. In 2008 and 2014 two case reports have described anecdotal cases, both in MSM [11, 12]. Moreover, to our knowledge, between 2009 and 2014 only two studies have been conducted in Italy to assess the prevalence of anal CT Lb2 serovar infection among MSM. The prevalence of this serovar among asymptomatic individuals attending urban STI Clinic in Turin and Bologna was 1.4% and13.1%, respectively [7, 13]. One of these Italian studies also showed CT-DNA in 9.4% of 2660 anal swabs [7].
Generally, the individuals with anal CT Lb2 serovar infection show a history of neglected symptoms at anal level. In fact, signs and severe discomfort related to long lasting proctitis were found in 86.5% of MSM infected by L2 serovar in Turin [7]. Consistently, a long lasting unrecognized anal syndrome was identified also in the MSM diagnosed with LGV at our center in 2015–2016.
Both in Turin and in our study the majority of LGV cases observed in MSM were diagnosed in HIV-infected individuals on cART (i.e., 95% of cases in Turin and 100% in Rome). The fact that all the cases recently diagnosed have been observed in MSM suggests that anal mucosa could represent an efficient reservoir for CT infection in the MSM community and explain the maintenance of an elevated risk of secondary transmission of infections, particularly among HIV-infected patients.
Notably, the LGV proctitis in our case series was mainly observed in individuals who referred specific receptive anal practices (fisting, sharing of sex toys). As also previously described by others, these sexual practices may play a major role in the spread of STIs among MSM [14, 15]. In fact, they may cause a higher risk of parenteral exposure, thus enhancing the circulation of CT L2b serovar. Sexual behaviour at greater risk is generally reported by “LGV-repeater” patients, i.e., those with LGV re-infections, commonly reported (5.2% of prevalence among all LGV diagnoses) in “endemic” countries, such as UK, and among HIV-positive MSM [16].
In USA and Europe, Chlamydia serology is considered useful to support the diagnosis of LGV in the appropriate clinical context [5]. Nevertheless, to date, there is not unanimous agreement regarding the laboratory methods for LGV diagnosis. Although NAATs are sensitive and specific, there is still a need to identify univocal microbiological approaches. Additionally, in Italy, these methods are not easily available for all STI clinics and some laboratories use home-made CT genotyping tests. We consider the use of these diagnostic tests as mandatory tools for a correct diagnosis, particularly in doubtful and clinically non-specific cases (LGV proctitis or inflammatory bowel disease). In our experience, the increase in the rate of high-risk patients complaining for anal symptoms has led to the use of new methodologies for the molecular diagnosis of CT serovars involved in LGV etiology.
The characteristics of the reported cases of LGV diagnosed in our center seem to suggest a recent increase of circulation of CT L2b serovar infection among MSM. This increase seems to be associated with the spreading of high risk sexual behaviours, particularly among patients living with HIV. Urgent interventions to enhance awareness of the health specialists about LGV are needed. Prevention programmes that involve multidisciplinary teams can be also useful to reduce the number of late diagnoses and to limit LGV transmission.
This study has a few limitations. Firstly, the case series was collected from a single STI center, therefore the number of the cases observed is limited. Secondly, the possibility of sexual contacts among the cases was not investigated. Thirdly, CT infection was not routinely searched for among high-risk individuals attending our STD center. Finally, we cannot exclude the influence of the “clinicians’ attitude” on the trend of LGV cases, i.e., recent awareness of the clinicians about LGV might have led to an increase of the diagnoses. Nonetheless, we believe that our findings still highlight a significant phenomenon, considering the rarity of LGV in developed countries. Consistently with the European guidelines for CT infection control, we sustain the need to investigate for CT anal infection all MSM attending an STI clinic, particularly those who refer any anal discomfort. Moreover, all MSM, particularly those who live with HIV infection, should be continuatively counselled about the risk of some receptive anal practices associated with LGV.