chlamydia

Chlamydia (STD)

ľ Chlamydia trachoma is a sexually transmitted disease that is transmitted by direct contact through oral, vaginal and anal intercourse and is also transmitted to newborns through vaginal birth by an infected mother. This disease is not passed on by indirect contact, such as a toilet seat. ľ Chlamydia trachoma is biologically active in vaginal and penile secretions and fluids. ľ The usual reservoir for C. trachoma is the mucous membranes of the body found in the genital region, throat, and eyes. ľ The etiological agent of Chlamydia is C. trachomatis which has the following general characteristics: obligate intracellular parasite gram negative coccoid bacteria nonmotile intracellular does not possess a peptidoglycan layer unable to produce its own ATP. ľ The following tests are used to identify C. trachomatis:

1) ELISA test and FA test may be effective only when the bacterium is metabolically active (not infectious), these tests are used to detect group specific LPS and strain-specific outer membrane proteins

2) gram staining (negative, coccoid)

3) culture and iodine staining for inclusion bodies (used because the trachoma species of Chlamydia cannot be stained with iodine because it does not contain glycogen)

4) Serological tests that detect high titer IgM antibodies indicates a recent infection (used in adults, cannot distinguish between current and previous infections, not very useful)

5) nucleic acid probes (these are currently new and further info was not available)

ƒæ The bacterium C. trachomatis was first discovered in 1907 by Stanislaus von Prowazek in Berlin. The genus part of the name, Chlalmydia, comes from the Greek word chlamys, which means cloak and the species part of the name, trachomatis is also Greek and means rough or harsh. This name is perfectly associated with the actions of this disease. ƒæ A cloak is meant to hide, conceal or even disguise; and that is what C. trachomatis does on the inside of the body, it hides, it is usually asymptomatic (no symptoms). It enters the body through mucous membranes on the body as elementary bodies that bind to receptors on the host cells and are taken in by endocytosis or phagocytosis. The elementary bodies become reticulate bodies that do not combine with the lysosome and are able to resist being digested and killed. The reticulate bodies reproduce by binary fission and change back into elementary bodies which leave by reverse endocytosis. The elementary bodies have a rough outer membrane that allows them to be resistant against ¡§harsh¡¨ environmental conditions which is associated with the name trachomatis.