Clinical, endoscopic and histological characteristics of Chlamydia trachomatis proctitis in males.

Objective: Chlamydia trachomatis is a prevalent cause of infectious proctitis, often misdiagnosed as cancer or inflammatory bowel disease (IBD). This study aims to describe the main clinical symptoms, together with endoscopic and histopathological characteristics of C. trachomatis proctitis in the general population.

Patients and methods: A retrospective observational study was conducted at a single institution, identifying all cases of proctitis due to C. trachomatis infection, detected by real-time PCR in rectal biopsy or anal smear, with endoscopic assessment.

Results: A total of 28 male patients were included (median age 37, IQR 31-48). Among them, 20 patients reported having sex with males. Concomitant infections included HIV (n=10), Neisseria gonorrhoea (n=4), and Treponema pallidum (n=2). A history of sexually transmitted diseases was reported by 18 patients (64%). The main clinical symptoms were rectal bleeding (79%) and diarrhoea (43%). The main endoscopic findings were rectal erythema (71%) and ulcers (57%), with rectal (89%) and sigmoid inflammation (11%). In 5 cases (18%), a single isolated deep rectal ulcer was the only finding. In 16 cases (57.1%), neoplasia, IBD or fissure was suspected according to endoscopy. Histological findings included mixed inflammatory infiltrate of lamina propria (95%), cryptitis (54%), and crypt abscesses (32%).

Conclusions: Endoscopically detected C. trachomatis proctitis in men presents with worrisome symptoms and nonspecific rectal ulcers, with chronic inflammation histology. This generates doubts about differential diagnosis with IBD and rectal cancer.