Urine BK Polyomavirus Research Articles

Risk factors associated with hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation.

Hemorrhagic cystitis (HC) is a common complication of allogeneic hematopoietic stem cell transplantation (HSCT). The incidence is about 7% to 68%, and some patients have to suffer a long period of frequent, urgent, and painful urination, which brings great pain. This study aimed to analyze risk factors of HC and its effect on patient survival. We collected the medical records of 859 patients who underwent HSCT at our hospital between August 2016 and August 2020. Patients with and without HC were matched using propensity score matching at a 1:1 ratio based on sex, age, and diagnosis, and logistic regression analyses were used to identify factors associated with HC. We used Kaplan–Meier curves to analyze the survival rates of patients in the HC and non-HC groups. We also analyzed the relationship between BK viral load and the occurrence of HC using receiver operating characteristic curve (ROC) analysis. After propensity score matching, there were 131 patients each in the HC and non-HC groups. In the HC group, 89 patients (67.9%) had mild HC (stage II°) and 43 (32.1%) had severe HC (stage III–IV). The median interval between stem cell transplantation and HC development was 31 (3–244) days. Univariate analysis indicated that donor age, hematopoietic stem cell source, HLA, acute graft-versus-host disease, busulfan, anti-thymocyte globulin (ATG), total body irradiation, cytomegalovirus (CMV) (urine), and BK polyomavirus (BKV) (urine) were significantly associated with HC. ATG, CMV (urine), and BKV (urine) were independent risk factors for HC based on the multivariate analysis. The Kaplan–Meier survival analysis showed no significant difference between the HC and non-HC groups (P = .14). The 1- and 2-year survival rates in the HC group were 78.4% and 69.6%, respectively, and the corresponding rates in the non-HC group were 84.4% and 80.7%, respectively. ROC analysis indicated that a urine BKV load of 1 × 107 copies/mL was able to stratify the risk of HC. In conclusion, when the BKV load is >1 × 107, we need to be aware of the potential for the development of HC.

1382. A Prospective Epidemiological Study BK Polyomavirus DNAuria and DNAemia within the First Year after Kidney Transplantation

Abstract Background Screening and early detection for the preceding BK polyomavirus (BKV) DNAuria and DNAemia to prevent the occurrence of BK polyomavirus BKV-associated nephropathy (BKPyVAN) among kidney transplant (KT) recipients has not been universally utilized and never assessed in a setting where the resource is limited. Therefore, we aimed to investigate this entity’s incidence, risk factors, and outcome with this intervention at our institution. Methods A prospective study of KT recipients at a tertiary care transplant center in Bangkok, Thailand, was conducted between January 2019 and March 2020. All patients underwent preemptive monitoring of urine and plasma BKV DNA load, measured by quantitative real-time PCR at 1, 2, 3, 6, 9, and 12 months post-KT. Low- and high-level BKV DNAuria was defined as urine BKV DNA load of < and > 7log10 copies/mL, respectively. Low- and high-level BKV DNAemia was defined as plasma BKV DNA load of < and > 4log10 copies/mL, respectively. The incidences were calculated by Kaplan-Meier analysis. The chi-square or student’s T-test compared clinical characteristics between those with and without high-level BKV DNAuria as appropriate. Risk factors of high-level BKV DNAuria were analyzed using Cox proportional hazard model. Results Among 99 evaluable KT recipients, a mean (SD) age was 42 (11) years, 64.6% were male, and 69.6% received an induction immunosuppressive therapy. Within 12 months post-KT, the incidences of low-level BKV DNAuria, high-level BKV DNAuria, low-level BKV DNAemia, and high-level BKV DNAemia were 22.63%, 13.14%, 9.49%, and 5.11%, respectively. High panel reactive antibody (PRA) was associated with high-level BKV DNAuria at 6 and 12 months, (HR 1.02 [95% CI (1.00-1.04)], P=0.019) and (HR 1.02 [95% CI (1.00-1.04)], P=0.023), respectively. Underlying diabetes mellitus was associated with high-level BKV DNAuria (HR 3.49 [95% CI (1.28-9.51)], P=0.015) at six months; however, not at 12 months. There was no allograft rejection directly related to a reduction of immunosuppression for BKV infection observed. Conclusion BKPyV infection is also prevalent among KT recipients in a resource-limited setting, however, without unfavorable consequence. Those with high-level PRA and underlying diabetes could be at risk of high-level BKV DNAuria after KT. Disclosures All Authors: No reported disclosures

Optimized amplification of BK polyomavirus in urine

BK polyomavirus (BKPyV) is a ubiquitous pathogen that typically results in asymptomatic infection. However, in immunocompromised individuals, BKPyV viral shedding in the urine can reach 109 copies per mL. These high viral levels within urine provide ideal samples for next-generation sequencing to accurately determine BKPyV genotype and identify mutations associated with pathogenesis. Sequencing data obtained can be further analyzed to better understand and characterize the genetic diversity present in BKPyV. Here, methods are described for the successful extraction of viral DNA from urine and the subsequent amplification methods to prepare a sample for next-generation sequencing.

BKV VIRURIA AND VIREMIA DO NOT PREDICT HOSPITALIZATION FOR INFECTIONS AFTER KIDNEY TRANSPLANTATION

BK polyoma virus (BKV) infection after kidney transplantation, resulting from either reactivation of latent infection in the recipient or transmission through the donor kidney, is understood to be related to the intensity of immunosuppression. Infections after transplantation being a function of immunosuppression burden in general, we hypothesized that early BKV viruria and viremia could indicate the likelihood of individuals needing hospitalization for all infections. We conducted a retrospective study among living donor renal transplant recipients in a program without the routine use of induction immunosuppressive agents, to explore the association between BKV viruria at two months post transplantation and viremia, with hospitalisation for any infection. The electronic case records of all patients who underwent renal transplantation between 8/5/2016 (start of the program) to 31-10- 2019 at IQRAA hospital Kerala, were reviewed to collect data on BKV viruria, viremia and hospitalisation for infections. A total of 149 patients had undergone transplantation during the study period of which nine were excluded from analysis (four patients within two months of transplantation, three patients with non-functioning graft within two months, one death within two months and one patient lost to follow up). 48 patients (34.28%) were detected urine BKV positive by polymerase chain reaction (PCR) around two months after transplantation, 74 patients tested negative and no data were available in 18. 24 out of the 48 patients with viruria had documented viremia by PCR. Among the rest 16 had no viremia, while data were missing in eight. Of the 122 patients with urine BKV data available 100 were ABO compatible (ABOc) transplants and the rest ABO incompatible (ABOi). 39 patients out of the 122 patients (31.96%) with urine BKV data available required hospitalization for infection. The median time to first hospitalization for infection was 139 days The most common causes for first hospital admission with infection after transplantation included lower respiratory tract infection and urinary tract infection/graft pyelonephritis in seven patients each, followed by Cytomegalovirus infection in five. No significant association was documented for hospitalization with infection either for BKV Viruria (χ2 (1, N = 122) =0.28, p = 0.59) or BKV viremia(χ2 (1, N = 58) =0.41, p = 0.51). ABOi transplantation was also not found to be significantly associated with BKV viruria (χ2 (1, N = 122) =0.09, p = 0.75). In this retrospective single centre study of living donor recipients BKV viruria at two months post renal transplant and BKV viremia were not found to be associated with hospitalization for any infection. Viral load cut offs to define severity of infection were not used and could have led to the inclusion of patients with lesser degree of immunosuppression confounding the results.

Urine Donor-Derived Cell-Free DNA Helps Discriminate BK Polyomavirus-Associated Nephropathy in Kidney Transplant Recipients With BK Polyomavirus Infection.

Background: Studies have shown that plasma donor–derived cell-free DNA (dd-cfDNA) can predict renal allograft antibody-mediated rejection. This study was performed to evaluate the value of urine dd-cfDNA concentration and dd-cfDNA fraction (%) for discriminating BK polyomavirus-associated nephropathy (BKPyVAN) in kidney transplant recipients with urinary BK polyomavirus (BKPyV) infection.Methods: In this retrospective single-center observational study, we enrolled kidney transplant recipients who were diagnosed with urine BKPyV infection between August 2018 and May 2019 at the First Affiliated Hospital of Sun Yat-sen University. Urine dd-cfDNA was measured by using a novel target region capture sequencing methodology. The pathological diagnosis of BKPyVAN was confirmed by anti-SV40-T immunohistochemical staining and classified using the American Society for Transplantation schema. Receiver operating characteristic curve analysis was used to investigate the relations of urine dd-cfDNA and dd-cfDNA% to intrarenal allograft BKPyV infection states.Results: In total, 93 patients were enrolled, including 40 cases of proven BKPyVAN, seven cases of probable BKPyVAN, 23 cases of possible BKPyVAN, and 23 cases of resolving BKPyVAN. Urine dd-cfDNA level in proven BKPyVAN (22.09 ± 21.27 ng/ml) was comparable to that in probable BKPyVAN (15.64 ± 6.73 ng/ml, P = 0.434) but was significantly higher than that in possible BKPyVAN (5.60 ± 3.53 ng/ml) and resolving BKPyVAN (5.30 ± 3.34 ng/ml) (both Ps < 0.05). Urine dd-cfDNA% of proven BKPyVAN (0.71 ± 0.21) was lower than that of probable BKPyVAN (0.91 ± 0.04, P < 0.001), but was significantly higher than that of possible BKPyVAN (0.56 ± 0.30) and resolving BKPyVAN (0.46 ± 0.28) (both Ps < 0.05). For distinguishing biopsy-proven BKPyVAN from biopsy-excluded BKPyVAN, the discrimination capacity of urine dd-cfDNA (AUC: 0.842, 95% CI: 0.735, 0.918) was superior to that of plasma BKPyV DNA load (AUC: 0.660, 95% CI: 0.537, 0.769) with 0.181 (95% CI: 0.043, 0.319) difference between areas under ROC curves (P = 0.010).Conclusion: The elevated urine dd-cfDNA level may help discriminate BKPyVAN in kidney transplant recipients with BKPyV viruria.

BK polyoma virus nephropathy in hematopoietic cell transplant recipients

Background: The epidemiology of BK polyoma virus nephropathy in hematopoietic cell transplant recipients is poorly characterized. Kidney dysfunction after hematopoietic cell transplant is often attributed to treatment toxicities and kidney biopsies are rarely performed. Methods: We reviewed pathology-confirmed BK polyoma virus nephropathy cases in adult and pediatric patients who had undergone a hematopoietic cell transplant between 1 January 2015 and 31 December 2017 at our institution. Plasma and urine BK polyoma virus was assessed by a quantitative polymerase chain reaction assay and were obtained at the clinician discretion. Glomerular filtration rate was estimated by the Chronic Kidney Disease Epidemiology Collaboration equation. BK polyoma virus nephropathy was scored by the Banff Working Group Proposal. Results: Eight (7 adult and 1 pediatric) cases of BK polyoma virus nephropathy were identified among 685 hematopoietic cell transplant recipients, 14 of whom had undergone a kidney biopsy. Five patients (62.5%) had received a CD34+-selected peripheral blood hematopoietic cell transplant; two had received a cord blood allograft and one an unmodified peripheral blood hematopoietic cell transplant. Two patients developed acute graft-versus-host disease grade II. Early post–hematopoietic cell transplant BK polyoma viruria was documented with onset at a median of 54 days (range, 6–91) post–hematopoietic cell transplant and median urine BK polyoma viral load was 9.6 log10 copies/mL (range, 8.6–10.0). BK polyoma virus nephropathy was diagnosed at a median of 267 days after hematopoietic cell transplant (range, 133–637). At BK polyoma virus nephropathy diagnosis, all patients had decreased renal function with glomerular filtration rate (median 29 mL/min/1.73 m2; range, 9–98 ) and creatinine (median 2.4 mg/dL; range, 0.8–7.5) ; median plasma BK polyoma viral load was 6.3 log10 copies/mL (range, 5.5–7.1) and median CD4+ lymphocyte count was 82 cell/mcL (range, 21–172). Conclusions: We report eight biopsy-proven BK polyoma virus nephropathies in hematopoietic cell transplant recipients from a single center. BK polyoma virus nephropathy should be considered in hematopoietic cell transplant recipients with worsening kidney function and high BK polyoma viremia.

JC Viruria Is Associated With Reduced Risk of Diabetic Kidney Disease

African Americans who shed JC polyomavirus (JCV) in their urine have reduced rates of nondiabetic chronic kidney disease (CKD). We assessed the associations between urinary JCV and urine BK polyomavirus (BKV) with CKD in African Americans with diabetes mellitus. African Americans with diabetic kidney disease (DKD) and controls lacking nephropathy from the Family Investigation of Nephropathy and Diabetes Consortium (FIND) and African American-Diabetes Heart Study (AA-DHS) had urine tested for JCV and BKV using quantitative PCR. Of the 335 individuals tested, 148 had DKD and 187 were controls. JCV viruria was detected more often in the controls than in the patients with DKD (FIND: 46.6% vs 32.2%; OR, 0.52; 95% CI, 0.29 to 0.93; P = 0.03; AA-DHS: 30.4% vs 26.2%; OR, 0.63; 95% CI, 0.27 to 1.48; P = 0.29). A joint analysis adjusted for age, sex, and study revealed that JC viruria was inversely associated with DKD (OR, 0.56; 95% CI, 0.35 to 0.91; P = 0.02). Statistically significant relationships between BKV and DKD were not observed. The results from the present study extend the inverse association between urine JCV and nondiabetic nephropathy in African Americans to DKD. These results imply that common pathways likely involving the innate immune system mediate coincident chronic kidney injury and restriction of JCV replication. Future studies are needed to explore causative pathways and characterize whether the absence of JC viruria can serve as a biomarker for DKD in the African American population.

Clinical significance of monitoring urine BK polyomavirus in patients with hemorrhagic cystitis after hematopoietic stem cell transplantation

Objective This study was aimed to analysis the relationship of BK polyomavirus (BKV) and hemorrhagic cystitis (HC) in patients who received hematopoietic stem cell transplantation (HSCT). Methods Data of 80 patients who received HSCT and took regular urine test every week from June 2015 to April 2018 in the Third Xiangya Hospital of Central South University was retrospectively analyzed, they were 35 females and 45 males (aged 20-40 years, median age 30 years), and 31 cases with acute myeloid leukemia (AML), 24 cases with acute lymphoblastic leukemia (ALL), 15 cases with aplastic anemia (AA), 4 cases with chronic myeloid leukemia (CML), 6 cases with other diseases such as myelodysplastic syndrome (MDS) in the study population.The positive rate and incidence of HC were analyzed. Patients who infected with the BK virus were divided into HC group and non-HC group according to occurrence of HC.BK viral load were compared in two groups. Urine BK viral load were analyzed after logarithmic transformation. Data that conforms to a normal distribution is expressed as mean ± standard deviation. t test, ANOVA and ROC curve were used to statistical analysis. Skewed data is expressed in median (interquartile range), non-normal distribution parameters were compared by Wilcoxon test. Results Among 80 patients, 43 recipients (53.75%) became urinary BK positive, with 19 patients developed HC (23.75%), all of the 19 HC patients have urinary BK positive, and none of 37 BK-negative patients developed HC; the urine BKV level of the initial time and the peak time in HC group were (7.59±2.46) lg copy/ml, (10.56±1.71) lg copy/ml, the urine BKV level of the initial time and the peak time in non-HC group were (5.75±2.10) lg copy/ml, (7.31±2.29) lg copy /ml. The urine BKV level of the initial time and the peak time in HC group was higher than in non-HC group (t=2.642, P=0.012 and t=5.147, P=0.000 respectively), when analyzing the urine BKV level of the initial time in HC group and non-HC group, the best threshold is 5.23 lg copy/ml(1.68×105 copy/ml), with a sensitivity of 84.20% and specificity of 54.17%, when analyzing the urine BKV level of the peak time in HC group and non-HC group, the best threshold is 9.75 lg copy/ml(5.62×109 copy/ml), with a sensitivity of 84.20% and specificity of 83.33%, area under curve of each other were 0.728 (95% CI 0.575-0.881) and 0.875 (95% CI 0.769-0.981) respectively. Conclusions The BK viral load is closely related with HC in HSCT patients. The cut-off level of 1.68×105 copy/ml when analyzing the urine BKV level of the initial time, and the cut-off level of 5.62×109 when analyzing the urine BKV level of the peak time, help to forecast or auxiliary diagnose HC.(Chin J Lab Med, 2018, 41: 858-862) Key words: Cystitis; Hematopoietic stem cell transplantation; BK polyomavirus; Viral load; Urinalysis

ECIL guidelines for the prevention, diagnosis and treatment of BK polyomavirus-associated haemorrhagic cystitis in haematopoietic stem cell transplant recipients.

To define guidelines for BK polyomavirus (BKPyV)-associated haemorrhagic cystitis (BKPyV-HC) after paediatric and adult HSCT. Review of English literature and evidence-based recommendations by expert consensus. BKPyV-HC occurs in 8%-25% of paediatric and 7%-54% of adult recipients undergoing allogeneic HSCT. Diagnosis requires the triad of cystitis, macro-haematuria and high urine BKPyV loads >7 log10 copies/mL, and exclusion of other relevant aetiologies. BKPyV viraemia is frequent and may serve as a more specific semiquantitative follow-up marker. No randomized controlled trials are available to inform antiviral prophylaxis or treatment. However, hyper-hydration and/or bladder irrigation showed limited prophylactic value. Fluoroquinolones are not effective for prophylaxis or treatment, but rather increase antibiotic resistance. Hyperbaric oxygen or fibrin glue is marginally effective based on small case series from correspondingly equipped centres. Although cidofovir has been reported to improve and/or reduce BKPyV viraemia or viruria, the current data do not support its regular use. BKPyV-HC remains a disabling unmet clinical need in HSCT that requires novel approaches supported by proper clinical trials.

The Impact of Donor Viral Replication at Transplant on Recipient Infections Posttransplant

Organ donors are often implicated as the source of posttransplant recipient infection. We prospectively studied kidney and liver donor-recipient pairs to determine if donor viral replication of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and BK polyomavirus (BKV) at transplant was a risk factor for posttransplant recipient infection and disease. Donors and recipients were studied for antibodies against CMV and EBV and for quantitative viral replication of CMV, EBV, and BKV in oral washes, urine, and whole blood pretransplant. Recipient testing continued every 3 months after transplantation. Demographic and clinical data on infections and graft and subject outcomes were obtained. The 98 donor-recipient pairs included 15 liver and 83 kidney transplants (18 of whom were children). No donor had detectable CMV replication; therefore, its impact on recipient CMV replication could not be analyzed. Donor EBV replication occurred in 22%, mostly in the oral wash and showed no impact on posttransplant recipient EBV replication (P=0.9) or EBV viremia (P=0.6) in kidney or liver recipients. Donor BKV replication occurred in 17%, mostly in the urine and although not associated with posttransplant recipient urinary BKV replication in recipients, it was associated with BKV viremia (P=0.02), and a significantly shorter time to BKV viremia (P=0.01) in kidney recipients. Donor replication of CMV or EBV did not impact posttransplant recipient viral replication in kidney or liver transplants. Donor urinary BKV replication is associated with recipient BKV viremia in kidney transplants.

Association of DNA Amplification With Progress of BK Polyomavirus Infection and Nephropathy in Renal Transplant Recipients

PurposeBK polyomavirus-associated nephropathy (BKVAN) is an important cause of renal allograft loss. Immunosuppression therapy in renal transplant recipients can lead to the reactivation of latent BK polyomavirus (BKV) infection, leading to BK viruria and viremia. This single-center study aimed to clarify the association between quantitative measurement of BKV DNA and the progression of BKV infection, and secondly to identify the risk factors associated with the evolution of viruria to viremia. MethodsWe retrospectively analyzed 266 patients who underwent renal transplantation in our center from October 2006 to February 2013. We examined the viral loads of BKV in urine and plasma by quantitative real-time polymerase chain reaction assay after screening all of the recipients by urinary sediment examination. BKVAN was diagnosed by histological examination with immunohistochemistry of the large T antigen in biopsy specimens. ResultsOverall, 22 recipients showed BK viruria alone, whereas 22 progressed to BK viremia, of which 6 patients were diagnosed with BKVAN. Among BKVAN patients, 2 cases progressed to graft loss at 59 months and 31 months after diagnosis, respectively. In BKVAN group, the plasma viral loads were significantly higher than those in viremia without nephropathy (P < .001). Multivariate analysis revealed that the evolution of viruria to viremia was associated with recipient age over 55 years (odds ratio, 32.08; 95% confidence interval, 2.1–489.5) and tacrolimus exposure (odds ratio, 11.98; 95% confidence interval, 1.34–107.04). ConclusionsThe progression from viremia to BKVAN was strongly associated with increasing plasma viral loads for BKV DNA. The cutoff value of 1 × 104 copies/mL for plasma viral loads could differentiate between BKVAN and viremia alone. Further, recipient age over 55 years and tacrolimus exposure were independently associated with the evolution of viruria to viremia.

Lack of Cytomegalovirus and Polyomavirus Coexistence in Iranian Kidney Transplant Recipients

Introduction Maintenance of kidney graft function is essential, averting infection and coinfection. Cytomegalovirus (CMV) and BK polyomavirus (BKV) coinfection have been reported. There are a few studies of CMV and BKV infection in kidney transplant recipients in Iran, but no studies of their coinfection. Objective To assess the coexistence of CMV and BKV infection in renal transplant recipients. Patients and Methods The presence of CMV and BKV was assessed using real-time polymerase chain reaction in a cross-sectional study in 91 renal transplant recipients at 1 month posttransplantation. Assessment of CMV was performed only in blood samples, whereas BKV was assessed in both serum and urine samples. Results The 91 patients included 57 men (62.6%) and 34 women (37.4%), who ranged in age from 19 to 76 years. Simultaneous evaluation of CMV in plasma and BKV in urine demonstrated no significant association. Of 24 patients positive for BKV in urine, 8 (33.3%) were positive for CMV in plasma. Sixty-seven patients tested negative for BKV in urine, whereas 23 (34.4%) tested positive for CMV, which is unremarkable. Comparison of coinfection with plasma CMV and plasma BKV demonstrated no significant correlation. In 3 patients positive for BKV in plasma only, 1 (33.3%) was positive for CMV, whereas in 88 patients negative for BKV in plasma, 30 were positive for CMV. Conclusion No significant association was observed between CMV and BKV infections in kidney transplant recipients.