Human chlamydial infections

Chlamydiae are obligate intracellular parasites, bacteria with a peculiar biology. They belong to the genus Chlamydia which includes two species: C. psittaci and C. trachomatis. A wide range of hosts, including birds, mammals and man can be infected by chlamydiae. The diseases chlamydiae can produce include psittacosis, lymphogranuloma venereum, trachoma, inclusion conjunctivitis, urethritis, cervicitis, pelvic inflammatory disease, and neonatal pneumonia. The diagnosis of chlamydial infection may be made by visualization of the organism in direct smears, isolation of the agent in cell culture, or by demonstrating a significant rise in antibody titer. Chlamydial infection may be treated with tetracycline, erythromycin, or sulfonamides.