Inclusion conjunctivitis, or chlamydia keratoconjunctivitis, is an acute ocular inflammation resulting from infection by Chlamydia trachomatis—serotypes A through C (trachoma) and D through K (inclusion conjunctivitis). Trachoma is a major cause of worldwide blindness. Although inclusion conjunctivitis occasionally becomes chronic, the prognosis is generally good with treatment. If untreated, it may run a course of 3 to 9 months.
C. trachomatis is an obligate intracellular organism. It usually infects the urethra in males and the cervix in females and is transmitted during sexual activity.
Because contaminated cervical secretions infect the eyes of the neonate during birth, inclusion conjunctivitis is an important cause of ophthalmia neonatorum. Rarely, inclusion conjunctivitis results from autoinfection, by hand-to-eye transfer of the organism from the genitourinary tract.