Stability of JC Virus DNA in Cerebrospinal Fluid Specimens Preserved with Guanidine Lysis Buffer for Quantitative PCR Testing

Quantitative PCR testing for JC virus (JCV) DNA in the cerebrospinal fluid (CSF) is one of the diagnostic standards for progressive multifocal leukoencephalopathy (PML). The present study was conducted to examine its reliability using CSF specimens that had been preserved with guanidine lysis buffers in commercial nucleic acid extraction kits under different conditions. When CSFs were mixed with guanidine buffers, JCV DNA levels were not statistically reduced even after storage for 1 month at room temperature or for 3 months at -80 degrees C, compared with the control samples. In addition, the JCV DNA level was not decreased in a mixture of CSF and guanidine thiocyanate buffer incubated for 3 days at 56 C. These data suggest that CSF specimens mixed with commercial guanidine buffers can be stored without refrigeration, more safely handled, and directly subjected to JCV DNA testing for PML.