BK Virus Infection in Adult Renal Transplant Recipients; Risk Factors and their Impact on Allograft Survival

Abstract

Background: Since the discovery of BK Virus (BKV) in 1971, it became a growing challenge in the renal transplant field. Many hypotheses over the latest years have been made to justify the increased risk of acquiring BKV infection post-renal transplantation. Excessive immunosuppression remains the primary risk factor. Risk factors such as older recipients, male gender, prolonged cold ischemia time, ureteric stent insertion, degree of HLA mismatching and others have all been linked as additional risks for acquiring BKV infection. Nevertheless, the current literature on risk factors are inconclusive and no single identifiable risk factor can determine recipients who at risk. Objective:The objective of this review is to delineate and contemplate the potential risk factors published in the literature and leads to BKV nephropathy.Methodology: For this review, a variety of sources were utilised including EMBASE, Scopus, PubMed/Medline database and Google Scholar for observational studies on probable risk factors predisposing to BK viremia and/or nephropathy.Results: almost 22 distinctive risk factors were identified.Discussion: Over immunosuppression remains the major risk factor for acquiring BKV infection post-renal transplant, though it is uncertain whether the occurrence of BKVN (BKV Nephropathy) is owing to quantitative and/or qualitative differences in immune suppressants.Besides immunosuppression, other probable risk factors for BKV infection were recognized. Whilst some of them were reproducible in many of these studies, they were denied by others. For instance, ureteric stents, recipient's age, race, deceased-donor type and acute rejection episodes, were inconsistently recognised as significant risk factors for BKV infection. Conclusions:Over immunosuppression remained the reproducible risk factor for BKV infection in all studies, never the less published data on other risks factors varies. This may mirror the patient's geographical area, genetic vulnerability and probably a different BK gene variant with different risk susceptibility, these warrant further investigation.

Alport syndrome misdiagnosed with IgA nephropathy from familial history: a case report and brief review

“…Also, our center did not have patient follow-ups due to the Corona pandemic and distance problems. In the ESRD patients, transplantation is a good choice with excellent results, and recurrence of the disease after transplantation does not occur due to the donor usually having normal GBM, but the anti-GBM disease can ensue and has been reported [ 16 ]. A single Korean center also reported a higher incidence of BK virus nephropathy after transplantation in children with Alport [ 17 ].…”

Genotypes and Variants of BKPyV in Organ Donors after Brain Death

“…There is a large amount of data confirming the high prevalence of antibodies against BKPyV, which exceeds 90% in certain populations [ 18 , 19 ]. The detected frequency of viruria is usually lower among healthy people and mainly affects older groups, varying from 6% to more than 40% [ 20 , 21 , 22 ], and it increases particularly in patients undergoing immunosuppression, reaching over 50% in kidney transplant recipients [ 23 , 24 , 25 , 26 , 27 ]. Nevertheless, current reports [ 28 ] indicate a significantly higher prevalence of viruria, confirming the presence of BKPyV genetic material in the urine of over 90% of donors and in nearly 90% of recipients.…”

BK polyomavirus infection: more than 50 years and still a threat to kidney transplant recipients

“…Recipients who maintained graft function had a lower mean HLA match of 1.5 vs. 2.87 among those who lost their graft ( p = 0.001), thus postulating the lack of HLA matches as a predictor of better outcomes in patients with BKPyVAN ( 21 ). Some of the risk factors for post-transplant BKPyV replications are summarized in Table 1 ( 22 , 23 ).…”