Lymphogranuloma Venereum: Subacute inflammation of the inguinal lymph glands caused by certain immunotypes of CHLAMYDIA TRACHOMATIS. It is a sexually transmitted disease in the U.S. but is more widespread in developing countries. It is distinguished from granuloma venereum (see GRANULOMA INGUINALE), which is caused by Calymmatobacterium granulomatis.Proctitis: INFLAMMATION of the MUCOUS MEMBRANE of the RECTUM, the distal end of the large intestine (INTESTINE, LARGE).Chlamydia trachomatis: Type species of CHLAMYDIA causing a variety of ocular and urogenital diseases.Rectal Diseases: Pathological developments in the RECTUM region of the large intestine (INTESTINE, LARGE).Proctocolitis: Inflammation of the RECTUM and the distal portion of the COLON.Chlamydia: A genus of the family CHLAMYDIACEAE whose species cause a variety of diseases in vertebrates including humans, mice, and swine. Chlamydia species are gram-negative and produce glycogen. The type species is CHLAMYDIA TRACHOMATIS.Granuloma Inguinale: Anogenital ulcers caused by Calymmatobacterium granulomatis as distinguished from lymphogranuloma inguinale (see LYMPHOGRANULOMA VENEREUM) caused by CHLAMYDIA TRACHOMATIS. Diagnosis is made by demonstration of typical intracellular Donovan bodies in crushed-tissue smears.Ulcer: A lesion on the surface of the skin or a mucous surface, produced by the sloughing of inflammatory necrotic tissue.Chlamydophila psittaci: A genus of CHLAMYDOPHILA infecting primarily birds. It contains eight known serovars, some of which infect more than one type of host, including humans.Trachoma: A chronic infection of the CONJUNCTIVA and CORNEA caused by CHLAMYDIA TRACHOMATIS.Genital Diseases, Male: Pathological processes involving the male reproductive tract (GENITALIA, MALE).Homosexuality, Male: Sexual attraction or relationship between males.Genital Diseases, Female: Pathological processes involving the female reproductive tract (GENITALIA, FEMALE).Chlamydia Infections: Infections with bacteria of the genus CHLAMYDIA.Psittacosis: Infection with CHLAMYDOPHILA PSITTACI (formerly Chlamydia psittaci), transmitted to humans by inhalation of dust-borne contaminated nasal secretions or excreta of infected BIRDS. This infection results in a febrile illness characterized by PNEUMONITIS and systemic manifestations.Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Serotyping: Process of determining and distinguishing species of bacteria or viruses based on antigens they share.