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BK virus quantitation by PCR

Test Description

Quantitation of the BK polyomavirus in patient plasma or urine is performed using a virus-specific real-time PCR assay specific for the capsid protein gene of the virus. The lower limit of detection for this assay has been validated at 400 viral copies per milliliter of patient sample.

Specimens Suitable For Testing

Blood plasma and Urine are acceptable specimens for quantitative analysis. Whole blood should be collected in an EDTA or citrate tube (not heparin) – transported cold (not frozen) to arrive in lab within 4 hrs. LCRP will spin and prepare plasma for testing. If the blood cannot be gotten to LCRP in the requested amount of time, spin the sample and collect and freeze the plasma for transport. Frozen whole blood is NOT acceptable. Urine should be collected and frozen if possible before sending to the lab to be assayed.

If a qualitative test is desired, then formalin-fixed paraffin embedded tissue or frozen CSF samples can be assayed for the virus.

How to Order This Test

OHSU patients: Plasma and urine should be ordered as separate tests through EPIC.

**NOTE**
In order to ensure timely testing of urine specimens please make a separate aliquot of at least 1 milliliter, for BK testing specifically, before sending directly to Lab Central.

Outside OHSU:

  1. Please fill out the reference laboratory requisition form:http://www.ohsu.edu/pathology/wardman/forms/referencelaboratoriesreq.pdf

  2. Depending on shipping method, please send specimens to address listed below.

    • To Send Specimens by express mail:

      Knight Diagnostic Laboratories
      2525 SW 3rd Ave.
      Ste. 350
      Portland, OR 97201

For additional information, contact Knight Diagnostic Laboratory Services Center at 503-494-5400.

Charges and CPT Codes

CPT codes per requested test are the same for BKU (urine) and BKD (plasma) tests.

HB BK VIRUS, EXTRACTION 83890
HB BK, NUCLEIC ACID PROBE 83896
HB BK PCR, TARGET AMP 83898
HB BK PCR, SIGNAL AMP 83908
HB BK PCR, Pro fee 83912

Results reporting

The reported range of quantified results are between 400 and 5,000,000,000 copies per milliliter of patient sample. BKV positive results below the lower limit of quantification are reported as “Weak Positive”. Positive results greater than the upper limit are reported as “>5,000,000,000 copies per mL”.

Samples ordered in the OHSU system will be reported in Epic. For samples outside of OHSU, results will be faxed to the office of the physician ordering the test. Test results are usually generated 1 to 4 days after a sample is received by Lab Central. We will inform the ordering physician of any problems relating to specimen quality or resulting by e-mail (preferably) or by phone if a number is provided.