pelvic inflammatory disease (PID), general acute inflammation of the pelvic cavity in women, caused by bacterial infection of the cervix, uterus, ovaries, or fallopian tubes. The disease is most often transmitted by sexual intercourse and is usually the result of infection with gonorrhea or chlamydia. PID typically occurs in women who are under age 25 and are sexually active, who have multiple sexual partners, who have unprotected sex, or who have a history of sexually transmitted disease.

The symptoms of PID are similar to and may be mistaken for those of gonorrhea. They include pain in the abdomen and lower pelvis, chills, nausea, fever, and a thick and peculiarly odorous vaginal discharge. The major complication of PID is scarring of the fallopian tubes, with infertility often a consequence. The incidence of ectopic pregnancies (i.e., those in which the fertilized egg becomes embedded outside the uterus) is much higher in women with a history of PID. Some women develop chronic pelvic pain. Other complications include the development of abscesses on the fallopian tubes or ovaries, which can result in potentially dangerous infections.

The treatment of PID consists of antibiotic therapy to fight the infection. The diagnosis and treatment of male sexual partners of women with PID is also called for, since failure to do so exposes the women to further infections.

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Chlamydia, a genus of bacterial parasites that cause several different diseases in humans. The genus is composed of three species: C. psittaci, which causes psittacosis; Chlamydia trachomatis, various strains of which cause chlamydia, trachoma, lymphogranuloma venereum, and conjunctivitis; and C. pneumoniae, which causes respiratory-tract infections.

Sexually transmitted disease caused by C. trachomatis is characterized primarily by nongonococcal urethritis (infection of the urethra) in males and females and epididymitis (infection of the epididymus) in males. In men, nongonococcal urethritis has symptoms similar to those of gonorrhea. A gonorrhea-like discharge from the penis is the most prominent symptom. Painful urination may occur but is usually less prominent than with gonorrhea. The symptoms of nongonococcal urethritis appear one to four weeks after the infection has been contracted through sexual intercourse.

A chlamydial infection ordinarily produces few if any symptoms in women. There may be a slight vaginal discharge and pelvic pain. If untreated, however, C. trachomatis can seriously infect the cervix (causing cervicitis), the urethra (causing urethritis), or the fallopian tubes (causing salpingitis), and it can also cause pelvic inflammatory disease. Infection of the fallopian tubes can cause sterility, and a chlamydial infection also leads to a higher risk of premature births, ectopic pregnancies, and postpartum infections. A woman with an infected cervix may give birth to infected newborns who can develop pneumonia or the eye disease known as neonatal conjuctivitis.

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sexually transmitted disease: Chlamydia

C. pneumoniae was identified as a separate Chlamydia species in the 1980s. It causes various respiratory-tract infections, most commonly a mild, atypical pneumonia with symptoms of fever, cough, and sore throat.

In diagnosis it is important to eliminate gonorrhea as a cause for the symptoms. Specific tests for chlamydia include smears and cultures. The preferred treatment for chlamydial infections is tetracycline. Erythromycin and sulfonamide drugs have also been effective in treating the infections. Appropriate treatment produces a speedy recovery.

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