Detection and differentiation of human polyomaviruses JC and BK by LightCycler PCR

Human polyomaviruses JC and BK may cause several clinical manifestations in immunocompromised hosts, including progressive multifocal leukoencephalopa thy and hemorrhagic cystitis. Molecular detection by PCR is recognized as a sensitive and specific method for detecting human polyomaviruses in clinic al samples. In this study, a real-time PCR assay using the LightCycler plat form was evaluated and compared to an "in-house" PCR assay using a conventi onal detection method. A total of 122 urine specimens were tested, and huma n polyomavirus was detected in 49 specimens (40%) by both conventional PCR and LightCycler PCR. The remaining 73 specimens (60%) were found negative b y both assays. For 46 of the 49 positive specimens, LightCycler PCR and con ventional PCR identified the same polyomavirus type. These samples included 30 samples with JC virus (JCV), 14 samples with BK virus (BKV), and 2 samp les in which both viruses were detected. In the remaining three samples, bo th JCV and BKV were detected by the conventional assay, but only JCV was de tected by the LightCycler assay. The results of this study show that the Li ghtCycler PCR assay displays sensitivity and specificity similar to those o f a conventional PCR assay. These data, combined with its rapid turnaround time for results and decreased hands-on time, make the LightCycler PCR assa y highly suitable for the rapid detection and differentiation of JCV and BK V in the clinical laboratory.