The bacterium Ureaplasma often resides in the genitourinary tract of sexually active adults. These microorganisms are frequently considered commensal, meaning they can live within the body without causing harm or symptoms. However, Ureaplasma species can become opportunistic pathogens, triggering infections and contributing to various health complications. Assessing the risks it poses to reproductive and systemic health requires understanding the organism’s potential for pathogenicity.
Defining Ureaplasma Species
Ureaplasma species are categorized within the class Mollicutes, making them some of the smallest known free-living bacteria. A defining characteristic is the complete absence of a peptidoglycan cell wall, a feature shared with their relatives in the genus Mycoplasma. This structural lack renders common antibiotics like penicillin and other beta-lactams ineffective, as those drugs target cell wall synthesis.
The bacteria are named for their unique metabolic requirement: they must hydrolyze urea to generate energy, producing ammonia as a byproduct. This urease activity contributes to their potential for causing tissue damage due to local pH changes. The two species most relevant to human health are Ureaplasma urealyticum and Ureaplasma parvum. While U. parvum is the more commonly detected species, U. urealyticum is often considered to have a greater potential for causing disease, particularly in male urethritis.
Transmission Routes and Signs of Infection
The primary method of acquiring Ureaplasma is through sexual contact, including oral, vaginal, and anal routes. The bacteria are highly prevalent in the sexually active population, but their presence alone does not always indicate an infection requiring treatment. Colonization rates can be high, with the organism living in the mucosal tissues of the genital and urinary tracts.
A second route of transmission is vertical, passing from a pregnant person to the fetus or neonate, either in utero or during delivery. Most colonized individuals remain without symptoms, making active infection challenging to identify. When symptoms manifest, they are typically nonspecific and resemble other common urogenital infections.
In men, this can present as non-gonococcal urethritis (NGU), involving penile discharge, urethral discomfort, or a burning sensation during urination. For women, a symptomatic infection may appear as cervicitis, abnormal vaginal discharge, pain during urination, or lower abdominal discomfort.
Associated Reproductive and Systemic Risks
While often a harmless colonizer, Ureaplasma overgrowth or invasion can be associated with serious reproductive and systemic complications. The infection is linked to pelvic inflammatory disease (PID) in women, where it ascends into the upper reproductive organs, potentially causing endometritis or salpingitis. PID can result in long-term scarring and contributes to ectopic pregnancy and tubal factor infertility.
The presence of Ureaplasma species is implicated in adverse pregnancy outcomes. The organism is associated with an increased risk of miscarriage, stillbirth, and preterm birth, which is the leading cause of neonatal morbidity globally.
When Ureaplasma invades the amniotic cavity, it can trigger inflammation, leading to chorioamnionitis and premature rupture of membranes. This process involves the production of pro-inflammatory cytokines and enzymes that weaken the fetal membranes. Infants born prematurely due to this infection face increased risks for neonatal morbidities, including chronic lung disease, meningitis, and bronchopulmonary dysplasia.
In rare instances, particularly in immunocompromised individuals, Ureaplasma can cause systemic infection outside of the genitourinary tract. These disseminated infections can affect joints, leading to arthritis, or the central nervous system. For organ transplant recipients and other severely immunocompromised patients, the organism has been associated with systemic infections that can be severe or fatal.
Testing Procedures and Treatment Protocols
Diagnosis of Ureaplasma infection is performed using molecular methods, as the organism is difficult to isolate and grow. Nucleic Acid Amplification Tests (NAATs), such as Polymerase Chain Reaction (PCR), are the preferred diagnostic tools due to their high sensitivity. They can detect the organism in samples like first-void urine, urethral swabs, or vaginal swabs.
Testing is typically recommended only for symptomatic patients, individuals with recurrent non-gonococcal urethritis, or in specific high-risk pregnancy scenarios where infection is suspected.
The treatment regimen relies on specific classes of antibiotics that do not target the bacterial cell wall. Initial treatments include tetracyclines, such as doxycycline, or macrolides, like azithromycin. Doxycycline is often prescribed twice daily for seven days to treat symptomatic urethritis.
If a patient fails to respond to initial therapy, susceptibility testing may be performed to guide the selection of alternative drugs like moxifloxacin. Due to rising rates of antibiotic resistance, a sexual partner should also be treated to prevent reinfection.