Molecular Detection by Quantitative PCR

Quantitative PCR detection of BK virus.

Plasma, urine, fresh biopsies or fixed tissue. Please do not send whole blood. The sample volume required is as follows: plasma 2 mL (minimum 1 mL) and urine 20 mL (minimum 10 mL). 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.

Plasma or urine 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.

Confirmatory and reference testing for equivocal results or diagnostic complexities. Specimens for routine monitoring of transplant patients will not be accepted unless part of pre-arranged collaborative study.

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.

N/A

Quantitative multiplex qPCR based on TaqMan technology (1), detecting both JC and BK viruses. Analytical sensitivity between 10 and 100 copies of BK genome. Limit of quantification is 100 copies per reaction. The results are reported as copy number per mL of specimen. High copy numbers indicate greater probability of infection reactivation (in urine) and greater severity of infection. No quantitation possible on tissue biopsies. Please note that when testing formalin-fixed specimens, the presence of BKV 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.

1. 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.