Lymphogranuloma venereum is a sexually transmitted disease caused by Chlamydia trachomatis, serotypes L1, L2 and L3. The classical clinical manifestation is a painful inguinal lymphadenopathy, resulting without treatment in severe complications. Over the last years, however, the emergence of massive ulcerative proctitis has been observed, especially in men who have sex with men. Because the clinical symptoms are unspecific, Chlamydia trachomatis should actively be looked for. Reliable and rapid molecular tests have now been established to diagnose lymphogranuloma venereum. The therapeutic recommendation is tetracycline for 3 weeks. We present 5 cases to illustrate this disease.