Ureaplasma species, Molecular Detection, PCR
Rapid, sensitive, and specific identification of Ureaplasma urealyticum and Ureaplasma parvum from genitourinary, reproductive, and lower respiratory sources
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Ureaplasma species can cause acute urethritis and have been associated with bacterial vaginosis, preterm birth, and neonatal respiratory disease. Culture of Ureaplasma species is laborious, requiring a high degree of technical skill and taking several days. PCR detection is sensitive, specific, and provides same-day results. This PCR assay has replaced conventional culture for Ureaplasma urealyticum and Ureaplasma parvum at Mayo Medical Laboratories.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
A positive PCR result for the presence of a specific sequence found within the Ureaplasma urealyticum and Ureaplasma parvum ureC gene indicates the presence of Ureaplasma urealyticum or Ureaplasma parvum DNA in the specimen.
A negative PCR result indicates the absence of detectable Ureaplasma urealyticum and Ureaplasma parvum DNA in the specimen, but does not rule-out infection as false-negative results may occur due to the following; inhibition of PCR, sequence variability underlying the primers and/or probes, or the presence of Ureaplasma urealyticum or Ureaplasma parvum in quantities less than the limit of detection of the assay.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Interfering substances may affect the accuracy of this assay; results should always be interpreted in conjunction with clinical and epidemiological findings.
This assay was clinically validated in a blinded manner using 292 archived specimens submitted for Ureaplasma culture, 281 of which were in M4, M5, or Universal Transport Medium (UTM). The specimens consisted of 251 genitourinary, 32 reproductive fluids or tissues, and 9 respiratory specimens. Compared to culture, the PCR assay had 96.6% (141/146) sensitivity and 93.8% (137/146) specificity (p=0.29). Discordant results on the archived specimens (n=14) were tested by PCR by Dr. Kathleen A. Stellrecht at the Albany Medical Center (Journal of Clinical Microbiology 2004;42:1528-1533). Dr. Stellrecht found 5 of the 9 specimens that were PCR positive/culture negative to be PCR positive, and all of the 5 specimens that were PCR negative/culture positive to be PCR negative. The limit of detection of the assay is 100 targets/mcL for all validated sources. Additional whole organism Ureaplasma urealyticum and Ureaplasma parvum spiking studies (at the limit of detection of the assay) were performed using 30 each or more of the following: genitourinary swabs, respiratory specimens, genitourinary fluid, reproductive tissue/fluid, and kidney stones. All results (except for 1) were as expected.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Waites KB, Taylor-Robinson D: Mycoplasma and Ureaplasma. In Manual of Clinical Microbiology. 10th edition. Edited by J Versalovic. ASM Press, Washington, DC, 2011
2. Stellrecht KA, Woron AM, Mishrik NG, Venezia RA: Comparison of multiplex PCR assay with culture detection of genital mycoplasmas. J Clin Microbiol 2004;42:1528-1533
3. Kenny GE: Genital,mycoplasmas: Mycoplasma genitalium, Mycoplasma hominis, and Ureaplasma species. In Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. Edited by GL Mandell, et al. Churchill Livingstone, New York, 2008
4. Yoshida T, Maeda SI, Deguchi T, et al: Rapid detection of Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum organisms in genitourinary samples by PCR-microtiter plate hybridization assay. J Clin Microbiol 2003;41:1850-1855
5. Cunningham SA, Shannon SK, Rosenblatt J, Patel R: Comparison of culture and rapid polymerase chain reaction detection of Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum from genitourinary specimens. 48th Annual Infectious Diseases Society of America Meeting, 2010.