(klă-mid′ē-ă)

[Gr. chlamys, stem chlamyd-, cloak + -ia]
A bacterial genus of intracellular parasites of the family Chlamydiaceae with several recognized species, of which only one, Chlamydia trachomatis, infects humans. The organisms are characterized as bacteria because of the composition of their cell walls and their reproduction by binary fission, but they reproduce only within cells. These species cause a variety of diseases.
chlamydial (klă-mid′ē-ăl), adj.
SEE: Chlamydophila

Chlamydia trachomatis

A species that causes a great number of diseases, including genital infections in men and women. The diseases caused by C. trachomatis include conjunctivitis, epididymitis, lymphogranuloma venereum, pelvic inflammatory disease, pneumonia, trachoma, tubal scarring, and infertility.

INCIDENCE
C. trachomatis is a common sexually transmitted pathogen (causing more than a million infections in the U.S. annually). Infections are esp. common in sexually active young adults, between 18 and 26.

SYMPTOMS AND SIGNS
Men with chlamydial infection experience penile discharge and discomfort while urinating. Women may experience urethral or vaginal discharge, painful or frequent urination, lower abdominal pain, or they may not initially have any symptoms despite contracting pelvic inflammatory disease, which may result in chronic pelvic pain, ectopic pregnancies, or infertility.

DIAGNOSIS
Several tests for chlamydia are available, including cultures, antigen detection assays, ligase chain reactions, polymerase chain reactions, and enzyme-linked immunoassays.

PREVENTION
Transmission of the disease can be prevented by avoiding contact with infected people and by using condoms during intercourse. A pregnant woman with a chlamydial infection can transmit the disease to her newborn during birth. In newborns, ophthalmic antibiotic solution should be instilled in the conjunctival sac of each eye to prevent neonatal conjunctivitis and blindness caused by Chlamydia.

TREATMENT
Erythromycin, azithromycin, and tetracycline are effective.

Tetracyclines are generally not recommended for pregnant women or children under 8 years old.

PATIENT CARE
Young men and women should be educated about safe sexual practices, including abstinence and the use of barrier contraception. Education about sexually transmitted infections (STIs), including their symptoms, detection, treatments, and potential complications, should be incorporated into the health education provided to teenagers and young adults. Patients with symptoms of STIs should be advised to seek health care promptly.

Partner notification is advised for people with STIs. Laboratories that detect STIs should follow protocols for disease reporting.