Background BK polyomavirus (BKPyV) persistently infects the urinary tract and causes viremia and nephropathy in kidney transplantation (KTx), recipients. In a previous study, we observed an... Show moreBackground BK polyomavirus (BKPyV) persistently infects the urinary tract and causes viremia and nephropathy in kidney transplantation (KTx), recipients. In a previous study, we observed an increased incidence and load of BKPyV viremia in KTx patients coinfected with human polyomavirus 9 (HPyV9). Here we sought confirmation of this observation and explored whether novel HPyVs that have been detected in urine (HPyV9 and trichodysplasia spinulosa polyomavirus [TSPyV]) potentially aggravate BKPyV infection. Methods A well-characterized cohort of 209 KTx donor-recipient pairs was serologically and molecularly analyzed for HPyV9 and TSPyV coinfection. These data were correlated with the occurrence of BKPyV viremia and BKPyVAN in the recipients within a year after KTx. Results Seropositivity for HPyV9 (19%) and TSPyV (89%) was comparable between donors and recipients and did not correlate with BKPyV viremia and BKPyVAN that developed in 25% and 3% of the recipients, respectively. Two recipients developed TSPyV viremia and none HPyV9 viremia. Modification of the predictive effect of donor BKPyV seroreactivity on recipient BKPyV viremia by HPyV9 and TSPyV was not observed. Conclusions Our data provide no evidence for a promoting effect of HPyV9 and TSPyV on BKPyV infection and BKPyVAN in renal allograft patients. Therefore, we do not recommend including HPyV9 and TSPyV screening in KTx patients. Show less
The aim of the research described in this thesis was to obtain more insight in the risk factors of BK polyomavirus (BKPyV) infection after kidney transplantation (KTx), with special emphasis on... Show moreThe aim of the research described in this thesis was to obtain more insight in the risk factors of BK polyomavirus (BKPyV) infection after kidney transplantation (KTx), with special emphasis on pretransplantation related risk factors. Both donor and recipient as well as viral factors, were investigated. The ultimate goal was to identify reliable predictive markers of BKPyV infection after KTx, thereby providing opportunities to optimize and personalize the currently recommended BKPyV screening strategy. Chapter Two describes the correlation between pretransplantation donor-recipient pair seroreactivity against BKPyV and development of BKPyV viremia and BKPyVAN after KTx. In Chapter Three the stability of BKPyV seroreactivity in KTRs and healthy blood donors, and the correlation of BKPyV seroreactivity with preceding viremia in KTRs is described. In Chapter Four the reduced risk of BKPyV infection in HLA-B51 positive recipients after KTx is described. Chapter Five describes the development and evaluation of a Luminex bead-based multiplex immunoassay for BKPyV serotyping. In Chapter Six the application of the Luminex bead-based multiplex immunoassay for BKPyV serotyping is described in a cohort of KTx donor-recipient pairs. In the General Discussion implications for prediction of BKPyV infections in recipients after KTx, as well as suggestions for further research are described. Show less
