An in-house assay for BK polyomavirus quantification using the Abbott m2000 RealTime system

Area of Science:

• Virology
• Molecular Diagnostics
• Clinical Laboratory Science

Background:

• BK polyomavirus (BKPyV) quantification is crucial for managing renal transplant recipients.
• The Abbott m2000 RealTime System is a widely used platform for molecular assays.
• Developing in-house assays offers flexibility and potential cost-effectiveness.

Purpose of the Study:

• To validate an in-house quantitative real-time PCR (qPCR) assay for BKPyV viral load measurement.
• To target the BKPyV major capsid VP1 gene for accurate quantification.
• To assess the assay's performance on the Abbott m2000 RealTime System.

Main Methods:

• Validation of an in-house qPCR assay using the Abbott m2000 RealTime System.
• Testing of 95 clinical samples (urine and plasma) with known BKPyV status.
• Performance evaluation included limit of quantification, limit of detection, linearity, sensitivity, and specificity.
• Precision studies were conducted to assess inter-assay variability.

Main Results:

• The assay demonstrated a limit of quantification of 2.70 log10 copies/mL and a limit of detection of 2.25 log10 copies/mL.
• Sensitivity was 89.58% and specificity was 97.96% for qualitative analysis.
• Precision studies showed low inter-assay coefficients of variation (0.63% high positive, 4.38% low positive).
• Genotyping revealed predominantly BKPyV type I (95.45%).

Conclusions:

• The developed in-house BKPyV qPCR assay is a sensitive, specific, and precise method for viral load quantification.
• The assay is cost-effective and suitable for clinical laboratories utilizing the Abbott m2000 RealTime System.
• This validated assay can aid in monitoring BKPyV in renal transplant patients.