To identify BKPyV, the VP1 protein sequence was analyzed and classified into genotypes in 246 RTRs before and after RTx from deceased donors during a one-year observation period. Quantitative assessment of BKPyV was conducted via qPCR. Prior to RTx, genotypes I and IV were identified in the urine (7.27 × 106; 1.20 × 105) and in serum (5.75 × 104; 1.12 × 104). After RTx, genotype I was predominant; identification of DNAuria-BKPyV (62.07%) and BKPyV-DNAemia (55.56%) peaked after three months, and the highest DNAuria-BKPyV titer was also observed after three months (6.48 × 109), whereas the BKPyV-DNAemia titer did not peak until after six months (2.21 × 107). The highest number of copies of genotype IV in the urine was observed after six months (9.54 × 109), while the highest titer in the serum was not observed until after 12 months (3.88 × 106). DNAuria-BKPyV precedes BKPyV-DNAemia, affects a larger group of patients, and has a greater and more easily detected viral load, which makes it not only an earlier marker, but the key predictive marker of greater clinical value than later detection of BKPyV-DNAemia alone. Early monitoring of DNAuria-BKPyV should be the basis of classical screening, and not merely an addition to it, and therapeutic interventions should be undertaken early to prevent nephropathy.
Furmaga et al. (Fri,) studied this question.