Recent outbreaks of LGV in Western Europe and the USA have been reported since 2003. This epidemic has a preponderance for MSM and behaves differently to the classical LGV infection which is highly prevalent in parts of Africa, Asia and South America. Since 2004, over 1000 cases have been diagnosed in MSM with a new surge of cases in 2010. The L2 serovar of C trachomatis
has been identified as causing the current outbreak.1 2
The symptoms and signs of infection in MSM such as proctitis presenting as severe rectal pain, mucoid and/or haemorrhagic rectal discharge, tenesmus, constipation and other features of lower gastrointestinal inflammation1
; have led to incorrect diagnosis of IBD. This misdiagnosis has been described in case reports previously,3–5
the new surge in cases this year suggests that we need to raise awareness of LGV infection to ensure patients are managed appropriately.
Further analyses of reported cases has identified a pattern of LGV infection among white MSM, the vast majority of whom were HIV positive and co-infected with hepatitis C infection.1 2
While sexual behaviour may account for this finding, the ulcerative nature of LGV infection is likely to increase the transmission risk of HIV and other bloodborne viruses, in the same way as with other ulcerative sexually transmitted infections such as genital herpes.
Classical LGV infection follows three clinical stages – primary, secondary and tertiary. It occurs at the site of the infection (mouth, anus, or any part of male or female genitalia). The primary lesion presents as a painless sore which may go unnoticed, and the incubation period ranges over 3–30 days. The secondary stage follows the primary lesion by 10–30 days and typically causes systemic symptoms and lymphadenopathy. C trachomatis
serovars L1–L3 are lymphotropic, and cause disease by thrombolymphangitis and perilymphangitis. The LGV infection therefore manifests itself with inflammation and swelling of lymph nodes and surrounding tissue. Thus clinically, patients present with tender inguinal and/or femoral lymphadenopathy which may ulcerate and discharge pus from multiple points, creating chronic fistulae. The tertiary stage of the infection has also been referred to as the genito-anorectal syndrome. This describes a few patients who do not recover following the secondary stage of infection. In these patients C trachomatis
infection persists and causes a chronic inflammatory response, leading to destruction of involved tissues. Patients can present with proctitis, acute proctocolitis, rectal bleeding, fistulae, strictures and chronic destruction of the vulva. Lymphoedema of the genitals with persistent suppuration and pyoderma may result secondary to the destruction of lymph nodes.1 2
Diagnosis of LGV infection requires a rectal swab for Chlamydia (NAAT). Positive rectal Chlamydia results are subsequently genotyped in a reference laboratory for LGV infection. Rectal swabs are currently performed in genitourinary clinics for all cases of rectal sexual exposure with symptoms. National guidelines are set to change to ensure all UK genitourinary clinics offer rectal Chlamydia testing for all MSM reporting rectal exposure. Clinicians should have a low index of suspicion for an infective cause of rectal or bowel symptoms, and LGV infection should be excluded in all patients.
In addition, routine HIV testing will continue to identify a large number of patients with otherwise undiagnosed HIV infection, and we are actively trying to normalise this recommendation.6
HIV infection itself can cause bowel symptoms in over 50% of patients at some time during their illness, the most common infective causes are summarised in . In this case, misdiagnosis led to inappropriate treatment being initiated in a severely immunocompromised individual highlighting the importance of always considering a wide number of differential diagnoses.
Table 1 Other infective causes of bowel symptoms in HIV positive patients7 Learning points
- Consider a diagnosis of HIV infection in all cases of bloody diarrhoea and weight loss.
- Sexual history taking to establish anal intercourse in MSM will indicate the need to take rectal swabs for Chlamydia. Chlamydia swabs should be available in gastroenterology clinics and swabs should be taken in all with bowel symptoms.
- Cases of suspected LGV infection should be referred to GUM teams for confirmatory tests and testing and treatment of sexual partners to reduce the risk of onward transmission and re-infection.
- LGV infection is treated with 3 weeks of oral doxycycline 100 mg twice daily.