Test Code URPRP Ureaplasma species, Molecular Detection, PCR, Plasma
Useful For
Rapid, sensitive, and specific identification of Ureaplasma urealyticum and Ureaplasma parvum from plasma
This test is not intended for medicolegal use.
Method Name
Real-Time Polymerase Chain Reaction (PCR) using LightCycler and Fluorescent Resonance Energy Transfer (FRET)
Reporting Name
Ureaplasma PCR, PSpecimen Type
Plasma EDTASpecimen Required
The high sensitivity of amplification by polymerase chain reaction requires the specimen to be processed in an environment in which contamination of the specimen by Ureaplasma DNA is unlikely.
Collection Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Royal blue top (EDTA), pink top (EDTA), or sterile vial containing EDTA-derived aliquot
Submission Container/Tube: Screw-capped, sterile container
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot plasma into a plastic vial.
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma EDTA | Refrigerated (preferred) | 7 days | |
Frozen | 7 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Clinical Information
Ureaplasma urealyticum and Ureaplasma parvum have been associated with a number of clinically significant infections, although their clinical significance may not always be clear as they are part of the normal genital microbiota. U urealyticum and U parvum have been associated with urethritis and epididymitis. They may cause upper urinary tract infection and have been associated with infected kidney stones. U urealyticum and U parvum may be isolated from amniotic fluid of women with preterm labor, premature rupture of membranes, spontaneous term labor, or chorioamnionitis. They may also cause neonatal infections, including meningoencephalitis and pneumonia. In addition, U urealyticum and U parvum have been reported to cause unusual infections, such as prosthetic joint infection and infections in transplant recipients.
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Recently, U urealyticum and U parvum have been found to cause hyperammonemia in lung transplant recipients.(1) In lung transplant recipients with hyperammonemia, the ideal diagnostic specimen is a lower respiratory specimen (eg, bronchoalveolar lavage fluid), although U urealyticum and U parvum may also be detected in blood. Treatment directed against these organisms has resulted in resolution of hyperammonemia.
Culture of Ureaplasma species is laborious, requiring a high degree of technical skill and taking several days. Polymerase chain reaction (PCR) detection is sensitive, specific, and provides same-day results. In addition, PCR allows the differentiation of U urealyticum and U parvum, which is not easily accomplished with culture. PCR assay has replaced conventional culture for U urealyticum and U parvum at Mayo Clinic Laboratories due to its speed and equivalent performance to culture.
Reference Values
Not applicable
Interpretation
A positive polymerase chain reaction (PCR) result for the presence of a specific sequence found within the Ureaplasma urealyticum and Ureaplasma parvum ureC gene indicates the presence of U urealyticum or U parvum DNA in the specimen.
A negative PCR result indicates the absence of detectable U urealyticum and U parvum DNA in the specimen but does not rule out infection as false-negative results may occur due to inhibition of PCR, sequence variability underlying the primers and probes, or the presence of U urealyticum or U parvum in quantities below the limit of detection of the assay.
Cautions
Interfering substances may affect the accuracy of this assay; results should always be interpreted in conjunction with clinical and epidemiological findings.
Since Ureaplasma species may be part of the normal microbiota, results should be interpreted accordingly.
This test does not detect other mycoplasmas or ureaplasmas (including Mycoplasma pneumoniae, a common cause of community acquired pneumonia).
Supportive Data
Validation included spiking studies for each Ureaplasma species. Spiking studies were carried out using 30 EDTA whole blood and plasma samples spiked with genomic DNA for Ureaplasma urealyticum and Ureaplasma parvum (as well as 10 naive specimens). Sensitivity and specificity were 100% for both targets.
Method Description
This polymerase chain reaction (PCR) method employs a target-specific detection system including primers, as well as fluorescent resonance energy transfer (FRET) hybridization probes designed for the ureC gene of Ureaplasma urealyticum and Ureaplasma parvum. The LightCycler instrument amplifies and monitors target nucleic acid sequences by fluorescence during PCR cycling. This is an automated PCR system that can rapidly detect amplified product development. The detection of amplified products is based on the FRET principle. For FRET product detection, a hybridization probe with a donor fluorophore, fluorescein, on the 3' end is excited by an external light source, which emits light that is absorbed by a second hybridization probe with an acceptor fluorophore, LC-Red 640, on the 5' end. The acceptor fluorophore then emits light of a different wavelength that is measured with a signal that is proportional to the amount of specific PCR product. The process is completed in a closed tube system and the melting temperature of the probes allows differentiation of U urealyticum from U parvum.(Cunningham SA, Mandrekar JN, Rosenblatt JE, Patel R: Rapid PCR detection of Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum. Int J Bacteriol 2013;2013:168742 doi: 10.1155/2013/168742)
Day(s) Performed
Monday through Friday
Report Available
3 to 4 daysSpecimen Retention Time
7 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
87798 x 2
87999 (if appropriate for government payers)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
URPRP | Ureaplasma PCR, P | 69934-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
UPSRC | Specimen Source | 31208-2 |
44135 | Ureaplasma urealyticum PCR, P | 51988-4 |
44136 | Ureaplasma parvum PCR, P | 69933-0 |