Diagnosis and management of rectal syphilis-case report

The incidence and prevalence of syphilis are rising worldwide. Rectal syphilis is a rare condition with few reported cases in the literature and therefore often missed from differential diagnosis of atypical anorectal ulceration. We report a case of a 64-year-old male who presented with change in the bowel habit and a palpable rectal mass on examination. Colonoscopy revealed a small, ulcerated lesion in the rectum. However, histopathological analysis and radiological assessments were inconclusive. A cutaneous ulceration prompted a repeat biopsy and staining for spirochaetes, which was diagnostic of syphilitic proctitis. He was successfully treated with first line antibiotics via the Genitourinary Medicine clinic. With its increasing incidence, syphilis should be considered as a potential diagnosis of atypical anorectal ulceration. A complete sexual history including relevant risk factors should be taken and a full clinical examination performed actively looking for signs and symptoms of disease.