NAME: Ureaplasma urealyticum
SYNONYM OR CROSS REFERENCE: Non-gonococcal urethritis (NGU), non-specific urethritis (NSU), genital mycoplasma.
CHARACTERISTICS: First discovered in humans in 1937, the Mycoplasmataceae family is a unique pleomorphic prokaryote in that it cannot produce a cell wall in any circumstance, and its structural support is given by a triple-layered membrane Footnote 1. Ureaplasma spp. are urease-producing bacteria that appear as spherical or ovoid coccoid cells, and are the smallest self-replicating organisms at 0.2 – 0.8 μm in diameter Footnote 2-Footnote 4. In 2003, categorization of U. urealyticum was divided into two separate species: U. urealyticum (includes 10 serovars) and U. parvum (includes 4 serovars) Footnote 4.
PATHOGENICITY/TOXICITY: U. urealyticum and U. parvum are etiologic agents of persistent non-gonococcal urethritis (characterized by urethral discharge) Footnote 5, non-chlamydial urethritis, stillbirth or premature delivery, postpartum bacteremia, postpartum endometritis, chorioamnionitis, spontaneous abortion, perinatal morbidity and mortality, pneumonia, and wound infection post-caesarean section Footnote 1, Footnote 4, Footnote 6, Footnote 7. Common symptoms include dysuria, hypogastric pains, meatal swelling in both sexes, and urethrorrhoea Footnote 7, Footnote 8. Infection has also been linked to the development of neonatal pneumonia, chronic pyelonephritis Footnote 9, infertility, prostatitis, epididymitis, chronic urethrocysititis Footnote 10, urinary calculi, low weight in neonates, meningitis, chronic lung disease (also know as bronchopulmonary dysplasia, BPD), aortic graft infection, extragential diseases (including arthritis), subcutaneous intrarenal abscess in adults, and there is a speculated connection to Reiter’s syndrome Footnote 11.
EPIDEMIOLOGY: Worldwide – can be found in the genitourinary tract (mucosal surfaces of the cervix or vagina) of 40 – 80% of sexually active women, many of whom are healthy and asymptomatic Footnote 1, Footnote 4. They can also be found in the urethra of males, but at lower prevalence. Colonization is associated with young age (under 20), lower socioeconomic status, sexual activity with multiple partners, African-American ethnicity, and use of oral contraceptives Footnote 1.
HOST RANGE: Humans Footnote 12.
INFECTIOUS DOSE: Unknown for humans. It is less than 10 CCU (color-changing units) for mice and 104 CCU for guinea pigs Footnote 13.
MODE OF TRANSMISSION: Spread of the bacteria is commonly through sexual contact Footnote 12. Infected females may transmit the bacteria to the fetus or neonate by three routes: ascending intrauterine infection, through a haematogenous route by the umbilical cord, or passage through an infected maternal birth canal that can result in colonization of the neonate skin Footnote 1.
INCUBATION PERIOD: 10-20 days after sexual transmission Footnote 14.
RESERVOIR: Humans, women may be asymptomatic reservoirs Footnote 12.
DRUG SUSCEPTIBILITY: Susceptible to antibiotics that interfere with protein synthesis, such as tetracyclines, macrolides (such as clarithromycin and azithromycin), spectinomycin, and erythromycin. Doxycycline, cethromycin, telithromycin, quinolones (such as sparfloxacin, trovafloxacin, and WIN 57273), gemifloxacin, and garenoxacin have been found to have inhibitory effects in vitro, but have yet to be clinically tested because of potential effects on cartilage development Footnote 1, Footnote 15-Footnote 17. A combination of erythromycin and chloramphenicol can be used to eradicate the bacteria from cerebrospinal fluid.
DRUG RESISTANCE: Resistant to beta-lactams and vancomycin due to their lack of peptidoglycan, to sulfonamides or trimethoprim because they do not synthesize folic acid, to fluoroquinolones, and to low concentrations of lincosamides Footnote 1.
SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 1% sodium hypochlorite, 70% ethanol, and 2% glutaraldehyde Footnote 18.
PHYSICAL INACTIVATION: Heat-kill at 100°C for 15 minutes Footnote 19.
SURVIVAL OUTSIDE HOST: Extremely sensitive to drying and dehydration due to the absence of a cell wall, thus survival outside the host is severe restricted Footnote 1.
SURVEILLANCE: Monitor for symptoms. Confirm through serology. Polymerase chain reaction can be used to differentiate this species from the closely related U. parvum species Footnote 4, but is not routinely used for diagnosis purposes as actual differences between the species have not been confirmed. Bacterial culture can identify presence of U. urealyticum in the amniotic fluid, placental tissue, blood, cerebrospinal fluid (CSF), or upper and lower respiratory tracts and urethral and cervical swabs.
Note: All diagnostic methods are not necessarily available in all countries.
FIRST AID/TREATMENT: Administer proper drug therapy. Erythromycin in divided doses can be used as intravenous treatment for preterm neonates Footnote 1. A pilot study showed 11 neonates completing the treatment in 7 days; however, side effects may include hypertrophic pyloric stenosis, cardiac toxicity, and hepatotoxicity. A minimum treatment of 10 – 14 days is optimal.
IMMUNIZATION: No vaccines are currently available.
PROPHYLAXIS: None currently available. Antibiotics such as erythromycin can be used to decrease incidence of diseases caused by infection, such as histologic chorioamnionitis, and increase the latency period Footnote 20.
LABORATORY-ACQUIRED INFECTIONS: None reported to date.
SOURCES/SPECIMENS: Amniotic fluid, blood from maternal umbilical cord, placental tissue Footnote 1.
PRIMARY HAZARDS: Accidental parenteral inoculation Footnote 1.
SPECIAL HAZARDS: None.
RISK GROUP CLASSIFICATION: Risk Group 2 Footnote 21.
CONTAINMENT REQUIREMENTS: Containment Level 2 facilities, equipment, and practices for all work involving infectious or potentially infectious materials or cultures Footnote 22.
PROTECTIVE CLOTHING: Lab coat. Gloves when direct skin contact with infected materials or animals is unavoidable Footnote 22. Eye protection must be used where there is a known or potential risk of exposure to splashes.
OTHER PRECAUTIONS: All procedures that may produce aerosols, involve high concentrations or large volumes should be conducted in a biological safety cabinet (BSC) Footnote 22. The use of needles, syringes, and other sharp objects should be strictly limited. Additional precautions should be considered with work involving animals or large scale activities.
SPILLS: Allow aerosols to settle and, wearing protective clothing, gently cover spill with paper towels and apply an appropriate disinfectant, starting at the perimeter and working towards the centre. Allow sufficient contact time before clean up.
DISPOSAL: Decontaminate all wastes that contain or have come in contact with the infectious organism before disposing by autoclave, chemical disinfection, gamma irradiation, or incineration Footnote 22.
STORAGE: The infectious agent should be stored in leak-proof containers that are appropriately labelled.
REGULATORY INFORMATION: The import, transport, and use of pathogens in Canada is regulated under many regulatory bodies, including the Public Health Agency of Canada, Health Canada, Canadian Food Inspection Agency, Environment Canada, and Transport Canada. Users are responsible for ensuring they are compliant with all relevant acts, regulations, guidelines, and standards.
UPDATED: December 2011
PREPARED BY: Pathogen Regulation Directorate, Public Health Agency of Canada
Although the information, opinions and recommendations contained in this Pathogen Data Sheet are compiled from sources believed to be reliable, we accept no responsibility for the accuracy, sufficiency, or reliability or for any loss or injury resulting from the use of the information. Newly discovered hazards are frequent and this information may not be completely up to date.
Public Health Agency of Canada, 2011