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BK Virus Quantitative PCR (Viral Load)



Nucleic acid amplification assay for the detection and quantification of human polyomavirus BK virus (BKV) DNA extracted from plasma.

The assay used detects a specific target in the Large T antigen gene of BKV.


Diagnosis / monitoringĀ of BK (Polyoma) infection in renal transplant patients, maximum fortnightly.


BK virusĀ is the most common virus to infect renal transplants and the most important viral cause of graft dysfunction or loss.

BK virus is a double stranded DNA virus of the Polyomavirus family; most humans first encounter BK virus during childhood with a mild respiratory or asymptomatic infection (seroprevalence indicates >80% of adults have been infected.) After primary infection the virus becomes latent in the uroepithelium and renal tubular epithelial cells (kidney & urinary tract), for most people the virus will not cause any further problems. However, in individuals that are immunocompromised or immunosuppressed the virus can reactivate and begin to replicate. This is of particular concern in renal transplant patients as high level viral replication can lead to virally induced acute tubular injury, known as BK Virus associated nephropathy (BKVAN, or Polyoma Virus Nephropathy – PVN).



Specimen Container

Pink top (EDTA) 5ml

To request on EPIC

For electronic requesting using EPIC (RDUH ONLY):

Search for: ‘BK Virus Quantitative PCR‘ or test code ‘LAB1374


Processed locally in Microbiology at RDUH

Processing Time

5 days


BKV viral loads will be reported in IU/ml and where appropriate a log will be given.

Lower Limit of Detection 215 IU/ml

Lower Limit of Quantitation 215 IU/ml

Upper Limit of Quantitation 130,000,000 IU / mL

(Please note: the conversion factor to IU from copies is 1.3 IU/copy => 1 IU/mL equals approximately 0.8 copies/mL)


ELITech ELITe BeGenius

Useful Links

For Patients:

BK virus-associated nephropathy – Kidney Research UK

Specimen Labelling Procedure
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