urealyticum

Urealyticum is a species in the genus Ureaplasma, most often discussed as Ureaplasma urealyticum. It is a small, cell-wall–deficient bacterium in the Mycoplasmataceae family, class Mollicutes, notable for urease activity that hydrolyzes urea. It is part of the normal human urogenital microbiota but can be implicated in disease.

Cells are pleomorphic and very small, lacking a rigid cell wall and not seen on Gram stain. Growth requires cholesterol-containing media such as SP-4 or A7, and cultures are slow, often taking days to weeks.

Ureaplasma colonizes the human urogenital tract. Prevalence varies and many infections are asymptomatic. Transmission is mainly sexual, with possible vertical transmission during birth.

Clinical relevance includes nongonococcal urethritis in men and cervicitis in women; it may contribute to pelvic inflammatory disease, adverse pregnancy outcomes, and neonatal respiratory disease. Causality evidence is variable and infections are sometimes incidental.

Diagnosis relies on molecular methods (NAAT) from urogenital specimens or culture in specialized media. Gram staining is unreliable for detection.

Because Ureaplasma lacks a cell wall, beta-lactams are ineffective. Treatments include doxycycline or macrolides; some strains show macrolide resistance. Partner treatment may be considered to prevent reinfection.

Taxonomy now recognizes two species, Ureaplasma urealyticum and Ureaplasma parvum; many references discuss both as the U. urealyticum complex.