Molecular Detection by Quantitative PCR<<Return to Laboratory
Accredited by the Standards Council of Canada to Laboratory no. 594 - CAN-P-4E (ISO/IEC 17025)
Quantitative PCR detection of JC virus.
- Progressive multifocal leukoencephalopathy (PML)
Cerebrospinal fluid (CSF), CNS fresh biopsies or fixed tissue. Sample of CSF required is 600 µL (minimum 300 µL). Plasma 1 mL (minimum 0.5 mL) and urine 2 mL (minimum 1 mL) are also accepted. Serum will not be accepted. The assay has not been validated for this specimen type and precise quantitation cannot be assured. Minimum volume will not allow repeat testing of samples with equivocal results.
For plasma, collect blood in plasma preparation tube (PPT) or K2EDTA tube (plastic; lavender or pink top). Do not use heparin as an anticoagulant. Centrifuge tube at room temperature at 1,100RCF for 10-15 minutes. Aliquot plasma into separate tube. Collect CSF in a dry tube subject to classic conditions for carrying out lumbar punctures.
Plasma, urine or CSF may be stored and shipped refrigerated to NML within 48h of sample collection or must be stored and shipped frozen. Fresh biopsies must be stored frozen at all times and shipped on dry ice. Fixed tissue may be stored and shipped at room temperature.
Shipping of specimens shall be done by a TDG certified individual in accordance with TDG regulations. For additional information regarding classification of specimens for the purposes of shipping, consult either Part 2 Appendix 3 of the TDG Regulations or section 3.6.2 of the IATA Dangerous Goods Regulations as applicable.
For additional guidance on the transport of infectious substances in other languages, please click on the link below.
Suspected cases of progressive multifocal leukoencephalopathy (PML).
Completed "Viral STI, Polyoma and Herpesvirus Testing" requisition form including sender lab name, address and telephone number, patient identifier, date of birth or age, sex, specimen reference #, type of specimen, date collected, test requested and any other relevant clinical information.
Quantitative multiplex PCR based on TaqMan technology (1), detecting both JC and BK viruses. Analytical sensitivity between 1 and 10 copies of JC genome per assay. The results are reported as copy number per mL of specimen. No quantitation possible on tissue biopsies. Please note that when testing formalin-fixed specimens, the presence of JCV may not be detected due to the decreased sensitivity of the assay.
14 calendar days. STAT samples may be considered under special circumstances. Please contact the lab to inquire about shorter turn around time.
- Dumonceaux T.J., Mesa C., and Severini A. 2008. An internally controlled, triplex quantitative PCR assay for human polyomaviruses JC and BK. J. Clin Microbiol. 46:2829-2836.