Test Catalog

Test ID: QBK    
BK Virus, Molecular Detection, Quantitative, PCR, Plasma

Method Description Describes how the test is performed and provides a method-specific reference

Viral nucleic acid is extracted from clinical specimens. Primers are directed to the large T antigen gene, which is a conserved sequence specific for BK virus (BKV). This assay detects only BKV; it does not detect JC virus or Simian virus 40 (SV-40) (other polyoma viruses). Amplification and monitoring of the development of target nucleic acid sequences occurs after the annealing step during polymerase chain reaction (PCR) cycling. This automated PCR system can rapidly detect (30-40 minutes) amplicon development through stringent air-controlled temperature cycling and capillary cuvettes. The detection of amplified products is based on the fluorescence resonance energy transfer (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 and emits light that is absorbed by a second hybridization probe with an acceptor fluorophore, LC-Red 640, at the 5'-end. The acceptor fluorophore then emits a light of a different wavelength that can be measured with a signal that is proportional to the amount of specific PCR product. Quantitative standards are used to develop a standard curve. Specimens with unknown levels of BKV DNA are then compared to the standard curve to determine the copy level of the virus. Reportable range is from 1,600 IU/mL to 16,000,000 IU/mL.(Unpublished Mayo method)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.

Monday through Saturday; Varies

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

2 days

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Clinic Laboratories until the release of the test result

5 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

1 week

Performing Laboratory Location Indicates the location of the laboratory that performs the test