Molecular detection and characterization of BK and JC polyomaviruses in urine samples of renal transplant patients in Southern Brazil.

The human polyomaviruses JC (JCPyV) and BK (BKPyV) are widespread in the human population. Following the primary infection, virus reactivation may lead to nephropathy and graft rejection in renal transplant patients. This study was carried out to access the presence of BKPyV and JCPyV DNA in urine samples collected from renal transplant patients (n = 92) and healthy individuals (n = 88) in Porto Alegre, Rio Grande do Sul. The samples were submitted to a nested PCR. A significantly higher frequency (P < 0.001) of BKPyV was found in renal transplant patients (65.2%) in comparison to the control group (32.9%). JCPyV was detected equally in both groups. Phylogenetic analysis of both BKPyV and JCPyV amplicons demonstrates the presence of the BKPyV subtypes I and II, whereas for JCPyV, four different groups are found (1, 2, 3, and 4).