Ureaplasma

A genus of microaerophilic to anaerobic, nonmotile bacteria (family Mycoplasmataceae) with no cell walls. Gram-negative, they are predominantly coccoidal to coccobacillary elements, approximately 0.3 μm in diameter, which frequently grow in short filaments; colonies are generally small, 20–30 μm in diameter, and may have no zones of surface growth. U. hydrolyze urea with production of ammonia, and are found in the human genitourinary tract, occasionally in the pharynx and rectum. In males, they are associated with nongonococcal urethritis and prostatitis; in females, with genitourinary tract infections and reproductive failure; in neonates, they may cause pneumonia or meningitis. The type species is U. urealyticum. SYN: T-mycoplasma.

- U. urealyticum a species that has been isolated from the respiratory tract and central nerve system of newborns. It causes infections of the genitourinary tract, particularly urethritis; thought to be sexually transmitted and transmitted from mother to infant. The laboratory diagnosis is simplified through the use of urea-containng agar, permitting detection of the tiny colonies.

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urea·plas·ma yu̇-'rē-ə-.plaz-mə n

1) cap a genus of mycoplasmas of the family Mycoplasmataceae that are able to hydrolyze urea with the formation of ammonia and that include one (U. urealyticum) found in the human genitourinary tract, oropharynx, and anal canal

2) a mycoplasma of the genus Ureaplasma

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Urea·plas·ma (u-re″ə-plazґmə) [urea + Gr. plasma anything formed or molded] a genus of gram-negative bacteria of the family Mycoplasmataceae, consisting of pleomorphic, nonmotile, microaerophilic, coccoid or coccobacillary organisms that lack a cell wall, form extremely small colonies, and hydrolyze urea; they occur most commonly in the oropharynx and respiratory and urogenital tracts. The type species is U. urealyґticum. Called also T-strain mycoplasma (T for tiny).