A 49-year-old man presented with a 1-week history of abdominal pain, distension, diarrhoea and fatigue . CT of the abdomen and pelvis revealed peritonitis with no identifiable cause . Diagnostic laparoscopy was performed, which excluded gastrointestinal perforation . Peritoneal fluid tested positive for Chlamydia trachomatis and rectal swabs were positive for C. trachomatis serovars consistent with lymphogranuloma venereum (LGV). Additional blood tests also revealed a diagnosis of syphilis . This is a rare documented case of LGV peritonitis in a male without associated immunodeficiency . The patient recovered well following laparoscopic washout and a course of appropriate antibiotics.