Ureaplasma urealyticum and Ureaplasma parvum are microorganisms within the Mycoplasma family of bacteria which can affect the female urogenital tract. They are very commonly found within the vagina but their role in causing disease is uncertain. The Mycoplasma bacteria are sexually transmitted infections which may lay dormant for many years and patients are often asymptomatic. They may be the cause a vaginal discharge but more often they can be more troublesome in pregnancy when they may cause a spontaneous miscarriage and chorioamnionitis leading to preterm labour and delivery. The diagnosis of these bacteria can be established by taking a vaginal swab for culture or for polymerase chain reaction (PCR). Mycoplasma hominis is also a sexually transmitted infection and is known to cause pelvic inflammatory disease. Mycoplasma genitalium is a less common infection and is known to be a cause of urethritis in the male, however, its role in causing disease in the female genital tract is currently unclear. The speciation of the Mycoplasma organisms and how they are related to each other is outlined below.
The Mycoplasma class of bacteria are known as Mollicutes in the order of Mycoplasmatales and in the family of Mycoplasmataceae. Within this family there are 2 genera which are Mycoplasma and Ureaplasma. Currently 13 species of Mycoplasma are known to affect humans and 2 species of Ureaplasma can affect the lower genital tract.
Taxonomy of Mycoplasma species:
|• Mycoplasma||Mycoplasma pneumoniae
|• Ureaplasma||Ureaplasma urealyticum
The Mycoplasma species can involve the respiratory and genital tracts in humans to produce clinical disease:
|Respiratory:||Mycoplasma pneumoniae cause of atypical pneumonia|
|Genital tract:||Mycoplasma fermantans
In the female genital tract the Ureaplasma species & Mycoplasma hominis can be pathogenic and can cause the following complications:
|Pregnancy:||– spontaneous miscarriage
– postpartum infection
– chorioamnionitis causing preterm labour & preterm rupture of the membranes
|Gynaecology:||– pelvic inflammatory disease
– vaginal discharge
In the male genital tract the Ureaplasma species and in particular Mycoplasma genitalium can be the cause of:
– non-specific urethritis
– male factor infertility
The Mycoplasma organisms are a form of bacteria but lack a cell wall and are hence known as mollucites. They require stringent conditions for survival as intracellular pathogens within the body and like Mycoplasma hominis , both of the Ureaplasma species are aquired as sexually transmitted infections. The diagnosis of Ureaplasma infections of the lower genital tract can be difficult as the organisms do not grow in the usual culture medium but require specific enrichment media for identification. In the male adequate specimens are difficult to obtain and Mycoplasma genitalium in particular cannot be cultured at all but is able to be identified by molecular PCR testing which is only be performed in specialized laboratories.
The Ureaplasma organisms have been divided into 2 subtypes of Ureaplasma urealyticum and Ureaplasma parvum but can only be differentiated by PCR testing. The pathogenicity of the Ureaplasma microorganisms within the female genital tract is unclear and in fact many consider them to be part of the normal bacterial flora of the vagina. There is however, no doubt that when these organisms are detected in an appropriate clinical setting, treatment with antibiotics is strongly recommended in order to prevent complications.
Treatment of Ureaplasma urealyticum is with oral Doxycycline 100mg daily for 28 days with a similar course for the sexual partner. In pregnancy Erythromycin 250mg 3 times daily is the preferred treatment for Ureaplasma species and is usually taken for the duration of the pregnancy.