Background/introduction Lymphogranuloma Venereum (LGV), due to an invasive serovar of Chlamydia Trachomatis, is endemic in the United Kingdom in men who have sex with men (MSM). It is associated with the human immunodeficiency virus (HIV) and other sexually transmitted infections including hepatitis C.

Aim(s)/objectives We present a case of LGV mimicking a rectal tumour in a heterosexual male.

Methods The diagnosis of LGV was made following molecular diagnostic testing of an anal swab.

Results The patient presented as an emergency with a history of change in bowel habit, tenesmus and rectal bleeding. He had a past medical history of duodenitis and a family history of Crohn’s disease. Digital rectal exam revealed a circumferential rectal tumour, 2 cm from the anal verge. Features suggested a diagnosis of rectal cancer and radiological staging demonstrated extensive local infiltration and nodal involvement, supporting this diagnosis. Biopsies from colonoscopy however revealed severe proctitis with no evidence of malignancy. The local colorectal MDT meeting decided the patient would have neoadjuvant chemoradiotherapy and subsequent surgery based on response, after more biopsies. In the interim he presented with pending bowel obstruction resulting in a de-functioning colostomy and the patient tested positive for HIV prompting a referral to GUM physicians. Repeat MRIs captured the subsequent remarkable response to LGV treatment with Doxycycline.

Discussion/conclusion It is important for HIV testing to be incorporated as part of the management plan for colorectal malignancies.