Chlamydial Pneumonia (Encyclopedia of Medicine)
Chlamydial pneumonia refers to one of several types of pneumonia that can be caused by various types of the bacteria known as Chlamydia.
Pneumonia is an infection of the lungs. The air sacs (alveoli) and/or the tissues of the lungs become swollen, and the alveoli may fill with pus or fluid. This prevents the lungs from taking in sufficient oxygen, which deprives the blood and the rest of the body's tissues of oxygen.
There are three major types of Chlamydia: Chlamydia psittaci, Chlamydia pneumoniae, and Chlamydia trachomatis. Each of these has the potential to cause a type of pneumonia.
Causes and symptoms
Chlamydia trachomatis is a major cause of sexually transmitted diseases (called nongonococcal urethritis and pelvic inflammatory disease). When a woman with an active chlamydial infection gives birth to a baby, the baby may aspirate (suck into his or her lungs) some of the mother's bacteria-laden secretions while passing through the birth canal. This can cause a form of relatively mild pneumonia in the newborn, occurring about two to six weeks after delivery.
Chlamydia psittaci is a bacteria carried by many types of birds, including...
(The entire section is 887 words.)
Want to Read More?
Subscribe now to read the rest of this article. Plus get complete access to 30,000+ study guides!
Chlamydial Pneumonia (World of Microbiology and Immunology)
Chlamydial pneumonia is a pneumonia cause by one of several forms of Chlamydial bacteria. The three major forms of Chlamydia responsible for pneumonia are Chlamydia pneumoniae, Chlamydia psittaci, and Chlamydia trachomatis.
In reaction to infection, infected lung tissue may become obstructed with secretions. As part of a generalized swelling or inflammation of the lungs, the fluid or pus secretions block the normal vascular exchanges that take place in the alveolar air sacs. Blockage of the alveoli results in a decreased oxygenation of the blood and deprivation of oxygen to tissues.
Chlamydia pneumoniae (in older literature known as "Taiwan acute respiratory agent") usually produces a condition known as "walking pneumonia," a milder form of pneumonia that may only result in a fever and persistent cough. Although the symptoms are usually mild, they can be debilitating and dangerous to at risk groups that include the elderly, young children, or to individuals already weakened by another illness. Chlamydia pneumoniae spreads easily and the high transmission rate means that many individuals within a populationncluding at risk individuals can be rapidly exposed.
Species of chlamydiae can be directly detected following cultivation in embryonated egg cultures and immunofluorescence staining or via polymerase chain reaction (PCR). Chlamydiae can also be detected via specific serologic tests.
Chlamydia psittaci is an avian bacteria that is transmitted by human contact with infected birds, feathers from infected birds, or droppings from infected birds. The specific pneumonia (psittacosis) may be severe and last for several weeks. The pneumonia is generally more dangerous than the form caused by Chlamydia pneumoniae.
Chlamydia trachomatis is the underlying bacterium responsible for one of several types of sexually transmitted diseases (STD). Most frequently Chlamydia trachomatis results in an inflammation of the urethra (nongonococcal urethritis) and pelvic inflammatory disease. Active Chlamydia trachomatis infections are especially dangerous during pregnancy because the newborn may come in contact with the bacteria in the vaginal canal and aspirate the bacteria into its lung tissue from coating left on the mouth and nose. Although many newborns develop only mild pneumonia, because the lungs of a newborn are fragile, especially in pre-term babies, any infection of lung tissue is serious and can be life-threatening.
Specific antibiotics are used to fight chlamydial pneumonias. Erythromycin and erythromycin derivatives are used to combat Chlamydia pneumoniae and Chlamydia trachomatis. Tetracycline is usually effective against Chlamydia psittaci.
See also Bacteria and bacterial infection; Transmission of pathogens