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The BK virus (BKV) is a member of the polyomaviridae family of DNA viruses. BKV reactivates under a highly immunosuppressed state and causes renal dysfunction. In renal transplant patients, BKV infection leads to tubular impairment and loss of transplanted kidney grafts. However, few studies have reported on the relationship between BKV and lung transplantation. Adjustment of the dosage of immunosuppressants is needed in some cases, but the treatment method has not been established. Here, we report a case of BKV-associated viruria and viremia in a patient with lymphangioleiomyomatosis (LAM) after lung re-transplantation. A 44-year-old female refractory LAM patient who had undergone lung re-transplantation 3 months earlier was diagnosed with BKV-associated viruria and viremia. Urine cytology indicated decoy cells and the urine and serum polymerase chain reaction test was positive for BKV. As scheduled after re-transplantation surgery, immunosuppressive drugs were progressively reduced. This patient was considered to have experienced spontaneous BKV-associated viremia and viruria. Review of the literature suggested that 17%-42% of BKV-associated viruria cases have been reported after lung transplantation, but cases of BKV-associated nephropathy are rarely reported. Based on the present case, doctors involved in lung transplantation should monitor patients for BKV infection. Decoy cell monitoring by urine cytology is a useful screening method in the follow-up observation after lung transplantation. Early-stage interventions may prevent BKV-associated nephropathy even in patients who have developed BKV viremia, and sirolimus can be administered to patients with histories of BKV infection if they are carefully monitored., (Copyright © 2019. Published by Elsevier Ltd.)

Automation of viral diagnosis has led to an increase of BK virus (BKV) viral load (VL) requests. The aim of this study was to assess the suitability of serum creatinine (SCr) for controlling the demand and to study the clinical characteristics of BKV infection. This is a retrospective study including patients with BKV VL request during April-July 2017. Clinical records and SCr were analyzed. Five hundred samples from 333 patients were included; 61.4% of samples were from males (55.5 ± 14.8 years), and all belonged to transplant recipients (86.4% renal). BKV VL was detectable in 40 samples (8.0%) from 23 patients (6.9%), who presented high SCr (100% vs. 90.9%, P = 0.038). Most of detectable VLs (62.5%) belonged to patients in their first year post-transplant. Six patients with detectable VL (26.1%) developed clinical manifestations, most of them (83.3%) had a first BKV VL greater than 10,000 copies/mL (P = 0.001). In conclusion, SCr would be useful to identify suitable specimens for BKV VL testing without missing cases.

The present AST-IDCOP guidelines update information on BK polyomavirus (BKPyV) infection, replication, and disease, which impact kidney transplantation (KT), but rarely non-kidney solid organ transplantation (SOT). As pretransplant risk factors in KT donors and recipients presently do not translate into clinically validated measures regarding organ allocation, antiviral prophylaxis, or screening, all KT recipients should be screened for BKPyV-DNAemia monthly until month 9, and then every 3 months until 2 years posttransplant. Extended screening after 2 years may be considered in pediatric KT. Stepwise immunosuppression reduction is recommended for KT patients with plasma BKPyV-DNAemia of >1000 copies/mL sustained for 3 weeks or increasing to >10 000 copies/mL reflecting probable and presumptive BKPyV-associated nephropathy, respectively. Reducing immunosuppression is also the primary intervention for biopsy-proven BKPyV-associated nephropathy. Hence, allograft biopsy is not required for treating BKPyV-DNAemic patients with baseline renal function. Despite virological rationales, proper randomized clinical trials are lacking to generally recommend treatment by switching from tacrolimus to cyclosporine-A, from mycophenolate to mTOR inhibitors or leflunomide or by the adjunct use of intravenous immunoglobulins, leflunomide, or cidofovir. Fluoroquinolones are not recommended for prophylaxis or therapy. Retransplantation after allograft loss due to BKPyV nephropathy can be successful if BKPyV-DNAemia is definitively cleared, independent of failed allograft nephrectomy., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Polyomaviruses, like the BK-polyomavirus (BKPyV), can cause severe pathologies in immunocompromised patients. However, since highly effective antivirals are currently not available, methods measuring the impact of potential antiviral agents are required. Here, a dual fluorescence reporter that allows the analysis of the BKPyV non-coding control-region (NCCR) driven early and late promoter activity was constructed to quantify the impact of potential antiviral drugs on viral gene expression via tdTomato and eGFP expression. In addition, by cloning BKPyV-NCCR amplicons which in this protocol have been exemplarily obtained from the blood-derived DNA of immunocompromised renal transplanted patients, the impact of NCCR-rearrangements on viral gene expression can be determined. Following cloning of the patient derived amplicons, HEK293T cells were transfected with the reporter-plasmids, and treated with potential antiviral agents. Subsequently, cells were subjected to FACS-analysis for measuring mean fluorescence intensities 72 h post transfection. To also test the analysis of drugs that have a potential cell cycle inhibiting effect, only transfected and thus fluorescent cells are used. Since this assay is performed in large T Antigen expressing cells, the impact of early and late expression can be analyzed in a mutually independent manner.

Background: BK virus (BKV) is a significant cause of nephropathy in kidney transplantation. The goal of this study was to characterize the course and source of BKV in kidney transplant recipients., Methods: We prospectively collected pretransplant plasma and urine samples from living and deceased kidney donors and performed BKV polymerase chain reaction (PCR) and immunoglobulin G (IgG) testing on pretransplant and serially collected posttransplant samples in kidney transplant recipients., Results: Among deceased donors, 8.1% (17/208) had detectable BKV DNA in urine prior to organ procurement. BK viruria was observed in 15.4% (6/39) of living donors and 8.5% (4/47) of deceased donors of recipients at our institution (P = .50). BKV VP1 sequencing revealed identical virus between donor-recipient pairs to suggest donor transmission of virus. Recipients of BK viruric donors were more likely to develop BK viruria (66.6% vs 7.8%; P < .001) and viremia (66.6% vs 8.9%; P < .001) with a shorter time to onset (log-rank test, P < .001). Though donor BKV IgG titers were higher in recipients who developed BK viremia, pretransplant donor, recipient, and combined donor/recipient serology status was not associated with BK viremia (P = .31, P = .75, and P = .51, respectively)., Conclusions: Donor BK viruria is associated with early BK viruria and viremia in kidney transplant recipients. BKV PCR testing of donor urine may be useful in identifying recipients at risk for BKV complications., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objectives: New biomarkers reflecting the degree of immunosuppression in transplant recipients are needed to provide an optimal personalized balance between rejection and infection risks., Methods: For this purpose, we investigated TTV viremia dynamics in 66 kidney transplant recipients followed up for two years after transplantation, in relation to BK virus infection and graft rejection., Results: After transplantation, TTV viremia rose by ≥2 log 10 copies/mL from baseline to month 3, then declined by ≥1 log 10 copies/mL thereafter. Higher TTV viremia was associated with recipients of a deceased donor, a lower count of CD8+ T cells and a higher BKV viremia. Importantly, TTV loads were significantly lower in KTR who would later display graft rejection; indeed, patients with TTV viremia lower than 3.4 log 10 copies/mL at transplantation or lower than 4.2 log 10 copies/mL at month 1 had a higher risk of developing graft rejection in the two following years (hazard ratio (HR) at D0 = 7.30, p = 0.0007 and HR at M1 = 6.16, p = 0.001)., Conclusions: TTV viremia measurement at early times post transplantation predicts graft rejection and would represent a useful tool to improve kidney transplant monitoring., (Copyright © 2019 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

BK-virus (BKV) associated nephropathy (BKVAN) and BKV associated haemorrhagic cystitis (HC) are complications of BKV infection/reactivation in renal and allogeneic haematopoietic stem cell transplantation (HSCT) patients, respectively. The task of how to manage these diseases was given to the chair by the Swedish Reference Group for Antiviral Therapy (RAV). After individual contributions by members of the working group, consensus discussions were held in a meeting on 23 January 2018 arranged by RAV. Thereafter, the recommendations were published in Swedish on November 2018. The current translation to English has been approved by all co-authors. High BKV serum levels suggest an increased risk for BKVAN and potential graft failure. For detection of BKVAN, careful monitoring of BKV DNA levels in serum or plasma is recommended the first year after renal transplantation and when increased creatinine serum levels of unknown cause are observed. Notably, a renal biopsy is mandatory for diagnosis. To reduce the risk for progression of BKVAN, there is no specific treatment, and tailored individual decrease of immunosuppression is recommended. For BKV-HC, BKV monitoring is not recommended, since BK-viruria frequently occurs in HSCT patients and the predictive value of BKV in plasma/serum has not been determined. However, the risk for BKV-HC is higher for patients undergoing myeloablative conditioning, having an unrelated, HLA-mismatched, or a cord blood donor, and awareness of the increased risk and early intervention may benefit the patients. Also for BKV-HC, no specific therapy is available. Symptomatic treatment, e.g. forced diuresis and analgesics could be of use.

BK virus is the causative agent of polyomavirus-associated nephropathy, a major cause of kidney transplant failure affecting 1%-10% of recipients. Previous studies that investigated the viral source on the kidney recipient pointed that the donor is implicated in the origin of human polyomavirus BK (BKPyV) infection in recipients, but giving the low genetic variability of BKPyV this subject is still controversial. The aim of this study was to determine if BKPyV replicating in kidney recipients after transplantation is always originated from the donor. Urine and blood samples from 68 pairs of living donors and kidney recipients who underwent renal transplantation from August 2010-September 2011 were screened for BKPyV by real time polymerase chain reaction. Only three recipients presented viremia. When both donors and recipients were BKPyV positive, a larger fragment of VP1 region was obtained and sequenced to determine the level of similarity between them. A phylogenetic tree was built for the 12 pairs of sequences obtained from urine and high level of similarity among all sequences was observed, indicating that homology inferences for donor and recipient viruses must be cautiously interpreted. However, a close inspection on the donor-recipient pairs sequences revealed that 3 of 12 pairs presented considerably different viruses and 4 of 12 presented mixed infection, indicating that the source of BKPyV infection is not exclusively derived from the donor. We report that about 60% of the renal recipients shed BKPyV genetically distinct from the donor, confronting the accepted concept that the donor is the main source of recipients' infection., (© 2019 Wiley Periodicals, Inc.)

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 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., (© 2019 The Authors. Journal of Medical Virology Published by Wiley Periodicals, Inc.)

BK virus (BKV) nephropathy is a serious complication in renal transplant recipients due to the need for immunosuppression. Nearly 50% of renal transplant patients with BKV nephropathy experience a significant loss of function of the transplanted kidney. It is routine practice to screen renal transplant recipients regularly for BK viremia. In this study, we compared the performance of BKV quantitative polymerase chain reaction analyte specific reagents by ELITech and Luminex for measuring BKV viral load in plasma using the Roche Cobas® z480 instrument and the Luminex ARIES® platform, respectively. A total of 34 patients previously tested on the z480, with results spanning the test's linear range, were analyzed on the ARIES®. The BKV DNA copy number correlation between the 2 methods was very good, with an R 2 value of 0.96. The average difference in log copy number between the 2 methods was -0.3, indicating that the ARIES® method may have slightly greater analytical sensitivity. BKV quantification results were closely matched between the 2 different methods. The workflow with the ARIES® System is greatly simplified by elimination of DNA extraction and most hands-on steps. The high degree of automation allows samples to be tested as they arrive into the laboratory, resulting in enhanced patient care due to more rapid turnaround time for results back to the ordering physician., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Introduction: BK polyomavirus is ubiquitous and remains dormant in the urothelial tract, reactivating and replicating in the immunocompromised state especially in the setting of post-renal transplantation where it is believed to be directly oncogenic based on recent reports. Its oncogenic role in the immunocompetent host is controversial. This study aimed to investigate the association of BK polyomavirus in Urothelial Carcinoma., Material and Methods: Patients with suspected urothelial carcinoma (UC) admitted under Department of Urology over a period of one year were recruited and transuretheral bladder tumor (TURBT) resection was performed, along with sampling of cystoscopically normal-appearing urothelium away from the tumor. In addition, cystectomy specimens with UC were included, with sampling of grossly normal-appearing urothelium away from the tumor. Immunohistochemistry (IHC) for SV40 T-Antigen and chromogenic in situ hybridization (CISH) using BK polyomavirus specific probe was performed on the paired samples (tumor and normal)., Results: Twenty-three TURBT and 14 cystectomy specimens were assessed. None of the cases showed evidence of BK polyomavirus infection in tumor or in surrounding mucosa by IHC. CISH performed in ten cases were also found to be negative. In comparison, one post-renal transplant urothelial carcinoma in our experience showed diffuse SV40 staining., Conclusions: This study suggests that BK polyomavirus infection is not associated with urothelial malignancy in the immunocompetent setting unlike in the immunocompromised setting where it should always be investigated for., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: 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., Methods: 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., Results: 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., Main Conclusions: 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., (Copyright © 2019 Endocrine Society.)

Background: After reactivation the BK-polyomavirus (BKPyV) associated nephropathy (PyVAN) is observed in 1-10% of renal transplant recipients, of which up to 80% undergo graft failure. BKPyV reactivation after renal transplantation was associated with donor-derived serotypes against which the recipient has no immunological protection. However, PyVAN risk assessment seroactivity testing is a time-consuming and cost intensive process., Objectives: Since BKPyV serotypes can be attributed to distinct genotypes I to IV, in the present study we retrospectively analyzed whether a simple PCR-based BKPyV genotyping assay might be a fast and inexpensive method to assess the risk for PyVAN and transplant outcome already at early stages of BKPyV reactivation., Study Design: 56 patients who were renal transplanted and tested positive for BKPyV viremia were included into the study. The BKPyV-VP1-coding sequences were PCR-amplified, sequenced, and subjected to genotyping. For group specific analysis patients were grouped in genotype I (n = 46) and a second group including genotype II and IV (n = 10) and associated with their clinical outcomes., Results: The most abundant genotype I was detected in 46 of 56 (82%) patients, however, in the genotype II and IV group PyVAN was twice as frequent as compared to the genotype I group 24 months after transplantation (8 of 10 (80%) vs. 17 of 46 (37%); p = 0.001). Accordingly, graft failure was significantly more frequent in the genotype II and IV group (3 of 10 (30%) vs. 2 of 46 (4%); p = 0.007)., Conclusion: PCR-based BKPyV genotyping might represent a fast and inexpensive method to assess the risk for PyVAN and transplant outcome already at early stages of BKPyV reactivation even if matched samples of the donor are not available., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Polyomavirus BK infection is a common complication and a major cause of morbidity after kidney transplantation. Surveillance of kidney transplant recipients was threatened by reactivation of polyomavirus BK infection can lead to polyomavirus BK-associated nephropathy (PVN). Antiviral immunoregulatory markers like Gamma interferon (IFN-γ) might also affect the polyomavirus BK pathogenesis for its role in antiviral host defense, graft rejection, and regulative of the adaptive immune responses. After screening polyomavirus BK infection, using Real time PCR (Taq-Man), the possible association between polyomavirus BK infection with IFN-γ gene expression was assessed. The mRNA levels of IFN-γ was examined in (n = 23) polyomavirus BK infected and (n = 23) non-infected kidney transplant patients in comparison with healthy controls (n = 23), using an in-house Real time PCR (SYBR Green) assay. The correlation of IFN-γ expression with viral load as well as other variables was also performed. The mRNA expression level of IFN-γ was significantly higher in polyomavirus BK infected patients (fold = 58.47) compared with non-infected ones (fold = 4.62), and healthy controls (p = 0.002). IFN-γ expression was higher in patients with higher viral load (p = 0.001). IFN-γ expression was correlated with viral load (r = 0.7, p < 0.0001). Accordingly, polyomavirus BK infection can induce IFN-γ gene over expression in kidney transplant infected patients. The results emphasized on the determinative role of IFN-γ in the pathogenesis of activated polyomavirus BK infection and also its importance in managing the clinical complications after kidney transplantation due to virus reactivation, requiring further investigation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objective: To investigate the characteristics of BK virus (BKV) specific cellular immune response in the recipients who have early infection with BKV after renal transplantation., Methods: The recipients of renal allografts (n = 30) were divided into groups of BK virus nephropathy (BKVN), viruria, and viremia. The BKV load was observed with real-time fluorescence quantitative polymerase chain reaction in urine and blood every three months. The values of serum creatinine (SCr) were detected. The peripheral blood mononuclear cells (PBMCs) were cultivated with overlapping peptide pool containing BKV structural proteins VP1, VP2, and VP3, and regulatory proteins large tumor antigen (LT-Ag) and small tumor antigen (st-Ag), to stimulate in vitro specific cellular immunoresponse. Flow cytometry was used to measure the proliferation of CD3+/CD4+/CD8+ T and interferon [INF]-γ/interleukin [IL]-2/tumor necrosis factor [TNF]-α T cell subsets., Results: The BKV infection increased SCr values in recipients of renal transplantation. CD4+ T cells were dominant (>90%) in the in vitro cellular immunoresponse to VP1, VP2, VP3, LT-Ag, and st-Ag. At the presence of viremia and BKVN, IL-2/IFN-γ+/TNF-α+ CD4+ T cells showed significantly decreased in vitro cellular immunoresponse to VP1, VP2, and VP3 (p < 0.05), but insignificantly changed to LT-Ag and st-Ag (p > 0.05). For the cases of viruria and viremia, IL-2/IFN-γ+/TNF-α+ CD4+ T cells showed significantly higher in vitro cellular immunoresponse to VP1, VP2, and VP3 than to LT-Ag and st-Ag (p < 0.05). The immunogenicity of VP1 and VP3 was significantly higher than that of VP2 (p < 0.05)., Conclusions: The BKV infection increases SCr values, and CD4+ T cells are dominant in the in vitro BKV specific cellular immunoresponse in the recipients of renal transplantation. Viremia significantly decreased the immunoresponse to VP1, VP2, and VP3. There is the significantly stronger immunoresponse to VP1 and VP3 when compared with that to VP2, LT-Ag, and st-Ag, suggesting that VP1 and VP3 may be the major targets for the BKV specific immune response.

Objective: The most common cancer amongst women is breast cancer. Reports on the role of EBV, BKV, and JCV in the development of breast cancer are controversial. Hence, the aim of this study was to determine the frequency of EBV, BKV, and JCV in malignant breast tumors in comparison with benign ones., Results: A total of 300 breast biopsy tissues were included, of which 150 were malignant and 150 benign. After deparaffinization, tissues were subjected to DNA extraction. β-globin gene was amplified by PCR to evaluate the quality of extracted DNA. In house PCRs assay was performed to detect EBV, JCV, and BKV genome fragment. The mean age of malignant and benign groups was 45.0 ± 9.4 and 35.2 ± 12.1 years old. Out of 150 malignant samples, 146 were ductal, two lobular and two samples both invasive ductal and lobular carcinoma. In the benign group, 96, 52 and two samples were fibroadenoma, fibrocystic, and adenosis types, respectively. Genomic DNA fragment of EBV, BKV, and JCV was not found in any of the malignant and benign breast tissues., Conclusion: According to our finding, there is the possibility that EBV, BKV, and JCV are not involved in breast cancer pathogenesis.

Background: There is no effective therapy for BK virus (BKV) nephropathy (BKVN). Cyclosporine A (CsA) has a lower immunosuppressive effect than tacrolimus. In vitro studies have shown that CsA inhibits BKV replication. The present study aimed to evaluate the effectiveness of switching from tacrolimus to low-dose CsA in renal transplant recipients with BKVN. Methods: Twenty-four patients diagnosed with BKVN between January 2015 and December 2016 were included. Tacrolimus was switched to low-dose CsA, and patients were followed for 24 months. Primary end points were BKV clearance in blood and graft. Secondary end points were urine specific gravity, serum creatinine, and graft loss. Results: The viremia in all patients cleared at a mean of 2.7 ± 2.0 months after switching to CsA. Urine specific gravity at 3 months after switching to CsA increased significantly compared with that at diagnosis ( P =0.002). The timing and trend of urine specific gravity increase was consistent with the timing and trend of blood and urine viral load decrease. Repeated biopsies at a median of 11.2 months (range: 9.1-12.5 months) after switching to CsA showed that 8 patients (42.1%) were negative for BKV, and 11 patients (58.9%) had a decrease in BKV load ( P <0.001). There was no statistical difference in the serum creatinine level between the time of diagnosis and 24 months of CsA therapy ( P =0.963). The graft survival rate was 100%. Only two patients (8.3%) suffered from acute rejection. Conclusion: Switching from tacrolimus to low-dose CsA may be an effective therapy for BKVN., (© 2019 The Author(s).)

Background: BKPyV is an important cause of premature graft failure after KT. Most clinical studies describe BKPyV infection in adult KT patients. We studied the prevalence of post-transplant BKPyV viremia, serology, and graft function in pediatric KT recipients., Methods: Forty-six pediatric patients transplanted between 2009 and 2014 were followed up for BKPyV DNAemia by plasma PCR for median 2.3 (range: 1-6) years. BKPyV-specific antibodies were retrospectively analyzed using virus-like particle ELISA. GFR was measured annually by 51 Cr-EDTA clearance, and serum samples were screened for DSAs by Luminex assay., Results: BKPyV viremia was demonstrated in nine patients at a median of 6 months post-KT. Early BKPyV viremia at 3 months post-KT associated with decreased concomitant GFR and tendency for decreased subsequent graft function. Three of nine patients with BKPyV viremia developed DSA, all against class II antigens. PyVAN developed to four patients and responded to judicious reduction in IS. One graft was lost later due to ABMR. BKPyV-IgG was found in 18 of 31 patients (58%) tested at transplantation, and seven recipients seroconverted after transplantation with a significant increase in IgG levels with IgM. Finally, BKPyV-IgG was detectable in 31 of 40 patients (78%) at the end of the study., Conclusions: Post-transplant BKPyV viremia in pediatric KT patients may alter graft function and contribute to progression of chronic allograft injury. BKPyV-IgG predicts past exposure. Low or absent BKPyV-specific antibody levels were seen pretransplant in 42% of tested patients, but were not predictive of prolonged replication or poor outcome., (© 2018 Wiley Periodicals, Inc.)

Objectives: This study aimed to verify the presence of polyomavirus BK (BKPyV) in the saliva of kidney transplant recipients and to correlate it with blood viremia., Material and Methods: We have conducted a cross-sectional study with a sample involving 126 renal transplant recipients. 126 samples of saliva and 52 samples of blood were collected from these patients. Detection and quantification of BKPyV were performed using a real-time PCR. To compare the presence of BKPyV in blood and saliva, the binomial proportion test was used. To verify associations between salivary shedding BKPyV and post-transplant periods (in months), the Mann-Whitney test was used. Spearman's correlation was used to correlate the viral load in the saliva with blood of kidney transplant recipients., Results: The mean age of the study group was 51.11±12.45 years old, and 69 participants (54.8%) were female, with a mean post-transplantation time of 4.80±6.04 months. BKPyV was quantified in several samples of saliva and blood, with medians of 1,108 cp/mL and 1,255 cp/mL, respectively. Only 16/52 (30.8%) participants presented BKPyV in blood, and 59/126 (46.8%) excreted the virus in saliva (p=0.004). BKPyV shedding was found in patients at a shorter post-transplantation period (3.86±5.25, p=0.100). A weak correlation was observed between viral quantification in saliva and blood (Spearman's correlation coefficient=0.193)., Conclusion: The results of this study suggested that, although saliva excretes more BKPyV than blood, there is no reliable correlation between salivary shedding and blood viremia, showing two independent compartments of viral replication.

Objectives: To investigate the prevalence of human polyomavirus (BK and JC viruses) infection in peripheral blood mononuclear cells of healthy blood donors., Methods: The study included 250 healthy blood donors. Five-milliliter blood was drawn into sterile EDTA tubes and PBMCs were isolated from whole blood. The isolated PBMCs were counted and stored at -70°C for future investigation. DNA was extracted and subjected to simple, sensitive and specific semi-nested PCR as well as QPCR using both general and specific primers for different assays., Results: Of 250 blood samples, 66 (26.4%) were positive for BKV DNA (146-34,514 copies/10 6 cells). JC DNA was found in 45 (18%) blood samples (65-21,250 copies/10 6 cells). Co-infection with these viruses were found in 11 (4.4%) out of 250 blood samples., Discussion: Our study provides important data on polyomavirus infection in peripheral blood mononuclear leukocytes in immunocompetent individuals. These data indicate significant differences between the prevalence of BKV and JCV infection in healthy blood donors. The prevalence of BK and JC virus infection is higher in the age range 30-39 years compared to other age ranges., (Copyright © 2019 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)

Objectives: After kidney transplantation, human BK polyomavirus (BKPyV) can induce a progressive disease, in three stages: viruria, viraemia, and then nephropathy after a few months of viral replication. Therapeutic intervention is recommended when BKPyV is detected in the plasma. The objective of our study was to assess urinary BKPyV nucleic acid test as a predictor for developing viraemia., Methods: We first defined a viruria threshold based on 393 time-matched urine and plasma samples collected after kidney transplantation; to validate this threshold, we followed-up a cohort of 236 kidney transplant patients., Results: A BKPyV viruria threshold of 6.71 log 10 copies/mL best discriminated between plasma-positive and plasma-negative patients (sensitivity 90.9% (95% CI 86.5-95); specificity 90.3% (95% CI 86.3-94.3); area under the curve 0.953 (95% CI 0.933-0.974). In the validation cohort, the risk of developing BKPyV viraemia at 1 year was 16.5% (39/236) and rose to 90.7% (39/43) if BKPyV viruria remained above the threshold of 6.71 for more than 1 month., Conclusions: Sustained BKPyV viruria is a reliable, early marker of patients at high risk of developing BKPyV viraemia. This marker should alert the clinician early, and thus allow timely therapeutic intervention., (Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

The uveal melanoma (UM) is the most common human intraocular tumor. The BK polyomavirus (BKPyV) is a small DNA tumor virus whose footprints have been detected in different human cancers. BKPyV has oncogenic potential. Indeed, BKPyV, when inoculated into experimental animals, induces tumors of different histotypes, whereas in vitro, it transforms mammalian cells, including human cells from distinct tissues. In this investigation, the association between UM and BKPyV was studied employing indirect enzyme-linked immunosorbent assays (ELISAs) using synthetic peptides that mimic BKPyV viral capsid 1 (VP1) antigens. Indirect ELISAs were used to detect serum IgG antibodies against this polyomavirus with oncogenic potential in samples from patients with UM and controls, represented by healthy subjects (HS). It was found that serum samples from patients with UM had a higher prevalence of BKPyV antibodies, 85% (51/60), compared with that detected in HS1, 62% (54/87), and HS2, 57% (68/120). The different prevalence of BKPyV antibodies detected in UM versus the two control groups, HS1 and HS2, is statistically significant (p < 0.005). Our immunologic data suggest a significantly higher prevalence of antibodies against BKPyV VP1 epitopes in serum samples from patients with UM compared with HS. These results indicate an association between UM and BKPyV, suggesting that this small DNA tumor virus may be a cofactor in the UM onset or progression., (© 2018 Wiley Periodicals, Inc.)

Background: Polyomavirus-associated nephropathy is associated with high risk of kidney allograft loss. Whether the cause of native end-stage renal disease influences the risk of BK infection is unclear., Methods: A retrospective, single-center study of 2741 adult kidney transplant recipients between 1994 and 2014 was performed. Recipients had end-stage renal disease due to polycystic kidney disease (PKD, n = 549), diabetes mellitus (DM, n = 947), hypertension (HTN, n = 442), or glomerulonephritis (GN, n = 803)., Results: A total of 327 recipients (12%) developed post-transplant BK viremia over a median follow-up time of 5 years. The incidence rate of BK viremia was lowest in patients with PKD (1.46 per 100 person-years) compared to other causes of ESRD (DM = 2.06, HTN = 2.65, and GN = 2.01 per 100 person-years). A diagnosis of PKD was associated with a lower risk of post-transplant BK viremia (adjusted HR (95% CI) = 0.67 (0.48-0.95), P = 0.02). BK nephropathy was significantly less common in patients with PKD (0.21 per 100 person-years) compared to those with HTN (0.80 per 100 person-years, P ≤ 0.001). Among patients with PKD, the risk of BK viremia was lower in patients with nephrectomy, compared to those without nephrectomy (adjusted HR (95% CI) = 0.42 (0.19-0.92), P < 0.05)., Conclusion: ESRD due to PKD is associated with a lower risk of post-transplant BK infection. The renal tubular epithelial cells in PKD are unique; they are in a proliferative but non-differentiated state. Whether this characteristic of renal tubular epithelial cells alters the BK viral reservoir or replication in PKD patients warrants further study., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: BK polyomavirus (BKPyV) continues to impact renal transplant recipients (RTR). The New England BK Consortium aims to jointly optimize screening and management of BKPyV., Methods: Our first project was to survey centers' BKPyV screening protocols and compare them to consensus guidelines., Results: Thirteen of 15 centers (86.7%) returned the survey. Only two center reported using monitoring parameters that were in line with consensus guidelines for BKPyV screening, while the majority of centers reported less intensive methods and shorter duration. One center reported performing renal biopsies in all patients with plasma viral loads >10 000 copies/mL, while all other centers only perform for-cause biopsies. For presumptive nephropathy, 11 centers recommend a biopsy for confirmation. For management of documented BKPyV-associated nephropathy, 12 centers propose further immunosuppression reduction. Nine centers report CNI dose reduction as their primary treatment. More than half of centers surveyed reported use of leflunomide, cidofovir or intravenous immunoglobulin., Conclusions: There was a large variance in BKPyV screening and management strategies among centers. Due to these results, all participating centers agreed to implement uniform screening and aim to optimize management protocols., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: BK virus (BKV) infection has become one of the main complications in renal transplant recipients (RTRs) with the arrival of newer potent immunosuppressive agents. However, reports on the epidemiology of BKV infection and risk factors in Chinese population after renal transplantation are scarce., Methods: From June 2015 to July 2016, living-donor renal transplant recipients (LDRTRs) who routinely received the quantitative BKV DNA testing of urine and plasma samples using quantitative real-time polymerase chain reaction (PCR) for the first time after transplantation were selected, while dialysis patients and healthy living donors during that period served as controls. Potential variables were compared and analyzed using logistic regression model multivariate analysis to assess the BKV infection related factors in LDRTRs., Results: Among the 52 LDRTRs identified, BKV DNA was detected in 16 urine samples (30.8%), significantly higher than that of dialysis patients (6.3%) and healthy living donors (4.2%) (p < .001). Nevertheless, no statistically significant difference wax noted between the latter two groups in urine samples (p = .842). Meanwhile, BKV DNA detection in blood samples was all negative in the three groups. Univariate analysis shown tacrolimus (Tac) trough level and lymphocyte percentage were associated with BKV infection in LDRTRs. Multivariate regression analysis also showed Tac trough level (HR, 1.644; p = .03), lymphocyte percentage (HR, 0.878; p = .026) were associated with BKV infection in LDRTRs., Conclusions: In Chinese population, the incidence of BKV infection increased significantly after living-donor renal transplantation. Significantly increased Tac trough level and decreased lymphocyte percentage might be the risk factors for BKV infection in LDRTRs.

Evolving BK polyomavirus-associated nephropathy (BKPyVAN) is characterized by tubulointerstitial inflammation that closely resembles acute T-cell-mediated allograft rejection if tubulitis is significant. The cellular composition of the inflammation varies during the course of BKPyVAN, and clusters of plasma cells may herald resolution of the infection. Less commonly, BKPyVAN can present with a predominance of histiocytes and granuloma formation. Granulomatous interstitial nephritis is uncommon in biopsies of either native or transplant kidneys. In both settings, this distinctive type of inflammatory response requires a systematic approach with careful clinicopathological assessment to determine its etiology. We present three patients with granulomatous BKPyVAN in the first year post-transplantation. These allograft biopsies at 4, 6, and 12 months post-transplant exemplify spontaneously resolving BKPyVAN, resolving infection after immunosuppression reduction, and early BKPyVAN, respectively. In immunosuppressed patients, BKPyVAN should be added to the relatively broad differential diagnosis of granulomatous tubulointerstitial nephritis., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: Renal impairment is a common complication after liver transplantation (LT). While BK polyomavirus (BKV) has been linked to renal failure in kidney transplant recipients, Torque teno virus (TTV) is a surrogate marker for immunosuppression that does not have a clear association with any human disease. The impact of BKV and TTV on renal impairment after LT is unknown., Methodology: In this retrospective study, urine and serum samples from 136 liver transplant recipients were screened for BKV and TTV by quantitative PCR. In addition, serum was screened for BKV-specific antibodies and the VP1 typing region was sequenced for BKV genotyping. All parameters were correlated with clinical data.Results/Key findings. BK viruria was detected up to 21 years after transplantation in 16.9 % of cases. BK viraemia was detected in 8.7 % of patients with BK viruria up to 4 years after LT. BKV-specific antibodies were detected in 93.6 % of all LT recipients and correlated with BKV viral load in urine. There was no correlation between renal impairment and the detection of BK DNA in urine (OR 0.983). TTV DNA was detected in 84.6 % of serum samples and in 66.6 % of urine samples. The TTV viral load in serum correlated with the BKV viral load but had no impact on renal impairment., Conclusion: Our data indicate that the detection of BKV and TTV is not a risk factor for renal impairment after LT. A correlation of TTV and BKV viral load seems to be an indicator for the immune status of the host.

BK virus (BKPyV)-associated nephropathy (BKPyVAN) may affect up to 10% of renal transplant recipients, causing graft failure in the absence of intervention. The dilemma in monitoring BKPyVAN in renal transplant patients has been that only testing urine BK viral load represents higher sensitivity (earlier detection) but lower specificity, while testing plasma BK viral load represents lower sensitivity (later detection) but higher specificity. However, blindly testing both urine and plasma inevitably contributes to unnecessary medical cost. We analyzed 1030 paired urine and plasma BKPyV viral load results and identified a reliable urine BKPyV viral load cutoff (4.0 log IU/mL) that can predict BKPyV viremia with 99.7% negative predictive value (NPV). We propose a cost-effective screening algorithm to first only monitor the urine BKPyV levels until the viral load reaches 4.0 log IU/mL, and then only monitor plasma with higher frequency. This approach ensures 98.7% sensitivity of catching the earliest BKPyV viremia onset, and 100% sensitivity of detecting the critical BKPyV viremia. In addition, we identified a urine BKPyV viral load cutoff of 6.7 log IU/mL as predictive of critical BKPyV viremia (defined as plasma viral load >4.0 log IU/mL) with 100% sensitivity and 100% NPV., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN) is a consequence of BKPyV replication in the urinary tract in kidney transplant recipients (KTR)., Objectives: The objectives were to determine the prevalence of BKPyV replication and BKPyVAN, risk factors associated to sustained viremia and BKPyVAN, and viremia cut-off that best predict the occurrence of sustained viremia and nephropathy in KTR of a single University Hospital Kidney Transplant Center., Patients and Methods: All KTR undergoing transplantation from August 2010 to December 2011 were enrolled and monitored up to 2 years posttransplantation for BKPyV viruria by decoy cells shedding or polymerase chain reaction (PCR) and viremia by PCR. Kidney biopsy was indicated if sustained viremia (two or more viremia above 10 000 copies/mL) to confirm BKPyVAN diagnosis., Results: In this study, 326 transplants were performed and 246 patients were included. Prevalence of viruria was 36.9%, viremia 22.3% and nephropathy 3.2%. Male gender was the only risk factor associated to sustained viremia or nephropathy. Cut-off value of viremia that best discriminates the progression to sustained viremia and to BKPyVAN was 37 488 and 44 956 copies/mL, respectively., Conclusions: Prevalence of viruria, viremia, and nephropathy were similar to those reported in literature but the cut-off value of viremia that best discriminates the risk of progression to nephropathy was greater than the value usually reported, which is 10 000 copies/mL., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

In immunosuppressed patients, BKPyV -variants emerge carrying rearranged non-coding control-regions ( rr-NCCRs ) that increase early viral gene region (EVGR) expression and replication capacity. BKPyV also encodes microRNAs, which have been reported to downregulate EVGR-encoded large T-antigen transcripts, to decrease viral replication in infected cells and to be secreted in exosomes. To investigate the interplay of NCCR and microRNAs, we compared archetype- and rr-NCCR-BKPyV infection in cell culture. We found that laboratory and clinical rr-NCCR-BKPyV -strains show higher replication rates but significantly lower microRNA levels than archetype virus intracellularly and in exosomes. To investigate whether rr-NCCR or increased EVGR activity modulated microRNA levels, we examined the ( sp1-4 ) NCCR-BKPyV , which has an archetype NCCR -architecture but shows increased EVGR expression due to point mutations inactivating one Sp1 binding site. We found that microRNA levels following ( sp1-4 ) NCCR-BKPyV infection were as low as in rr-NCCR -variants. Thus, NCCR rearrangements are not required for lower miRNA levels. Accordingly, Sp1 siRNA knock-down decreased microRNA levels in archetype BKPyV infection but had no effect on ( sp1-4 )- or rr-NCCR-BKPyV . However, rr-NCCR-BKPyV replication was downregulated by exosome preparations carrying BKPyV -microRNA prior to infection. To explore the potential relevance in humans, urine samples from 12 natalizumab-treated multiple sclerosis patients were analysed. In 7 patients, rr-NCCR-BKPyV were detected showing high urine BKPyV loads but low microRNAs levels, whereas the opposite was seen in 5 patients with archetype BKPyV . We discuss the results in a dynamic model of BKPyV replication according to NCCR activity and exosome regulation, which integrates immune selection pressure, spread to new host cells and rr-NCCR emergence.

Transplant recipients are more susceptible to bacterial and viral infections. Cytomegalovirus (CMV), Epstein-Barr virus (EBV), and polyomavirus BK (BK) are risk factors for graft dysfunction. All three of them are latent viruses that can cause serious disease in immunocompromised patients. Mainly qualitative PCR tests are required for diagnosis and quantitative monitoring, which are used to follow the response to transplantation. We developed a multiplex real-time PCR (qPCR) method to detect these viruses during blood screenings of transplant recipients. We also validated analytical and clinical performance tests using the developed multiplex qPCR. The limit of detection (LOD) was 100, 125, and 183 copies/ml for CMV, EBV, and BK, respectively. These results had high linearity (R 2 = 0.997) and reproducibility (CV range, 0.95-2.38%, 0.52-3.32%, and 0.31-2.45%, respectively). Among 183 samples, we detected 8 samples that were positive for CMV, while only 6 were positive for EBV, and 3 were positive for BK. Therefore, the viral infection prevalence in transplant candidates was 4.40% for CMV, 3.29% for EBV, and 1.64% for BK. This multiplex qPCR method should be used widely for diagnosing and monitoring latent viral infections in transplant recipients.

Background: Multiple risk factors for BK polyomavirus (BKPyV) replication after kidney transplantation have been described. Here, we investigated the impact of living donors' urinary BKPyV shedding and recipients' BKPyV antibody status pre-transplant on BKPyV replication during the first year post-transplantation., Methods: We assessed a cohort of living kidney donors and their paired recipients (n = 121). All donors were tested before transplantation, and recipients were tested before and after transplantation for BKPyV viruria and viremia. BKPyV-specific serology was assessed in all recipients at transplantation., Results: Ten of 121 donors (8.3%) had urinary BKPyV shedding pre-transplant, none had viremia. Overall, 33 (27.3%) recipients developed viruria after transplantation: 7 had received a kidney from a donor with BK viruria (7/10 positive donors) and 26 had received a kidney from a donor without BK viruria (26/111 negative donors; P = .0015). Fifteen (12.4%) recipients developed BK viremia after transplantation: 3 received a kidney from a donor with viruria (3/10 positive donors, 30%) and 12 received a kidney from a donor without viruria (12/111 negative donors, 11%; P = .08). One patient developed proven nephropathy. Ninety-one percent of recipients were seropositive for BKPyV. No relationship between recipients' sero-reactivity at transplantation and post-transplant BKPyV replication was observed. Pre-transplant donor urinary shedding was an independent risk factor for post-transplant BKPyV replication., Conclusion: Screening living kidney donors for BKPyV can identify recipients at higher risk for BKPyV replication after transplantation who may benefit from intensified post-transplant screening and treatment strategies., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: BK virus nephropathy (BKPyVAN) is a major complication in kidney transplant recipients (KTR) and typically occurs within 1 year of transplant. Guidelines vary in recommendations for BKPyV screening beyond 1 year. A systematic characterization of risk factors and outcomes of late-onset (>1 year) BKPyVAN has not previously been reported., Methods: We retrospectively compared characteristics and outcomes of early- (<1 year) and late-onset BKPyVAN (definitive [biopsy-confirmed] or presumptive [plasma BKPyV >10 000 copies/mL]) in a cohort of 671 KTR and simultaneous kidney-pancreas transplant (SPK) recipients between 2008 and 2013 at a single US transplant center. Proportions were compared using Chi-square or Fisher's exact test with P < .05 considered significant., Results: BKPyVAN was diagnosed in 96 (14.3%) patients (proven 16.7%, presumptive 83.3%): 79 (82.3%) early- and 17 (17.7%) late-onset. The proportion with late-onset BKPyVAN was significantly higher among SPK than KTR (4 of 7 [57.1%] vs 13 of 89 [14.6%], P = .017). Late-onset represented "de novo" infection (no BKPyV detection within the first year) in 14 (82.4%) and progression of earlier lower grade BKPyV reactivation in 3 (17.6%). Clinical outcomes were similar for early- and late-onset BKPyVAN (P > .05 all comparisons). In a pooled analysis of prior studies of BKPyVAN in SPK recipients, 62.9% (17 of 27) were late-onset., Conclusion: A significant proportion of BKPyVAN is late-onset, especially among SPK recipients, and supports a longer duration of BKPyV monitoring for SPK recipients than recommended in some guidelines., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: BK polyomavirus can lead to hemorrhagic cystitis (BKPyV-HC) in allogeneic stem cell transplantation and therefore to increased morbidity. No causal therapy has been established yet. Cidofovir (CDV) is a nucleotide analog of cytosine that is active against various DNA viruses and it has been described for therapy of BKPyV-HC using 2 admission routes: intravenous and intravesical., Methods: We performed a systematic review regarding the comparison of intravenous or intravesical cidofovir in the treatment of BKPyV-HC following adult allogeneic stem cell transplantation. Since there is a lack of randomized controlled trials, we considered all kinds of studies for this review. Due to heterogeneity of the data, we were not able to perform a meta-analysis, so the results are shown descriptively., Results: The literature search for primary studies yielded 232 results. Finally, 9 studies where considered which included a total of 189 adult patients with BKPyV-HC after allogeneic stem cell transplantation. We could only identify retrospective studies for this review. A total of 172 patients received intravenous CDV, 17 patients received intravesical CDV, and 2 patients received CDV in both admission routes. In 68.0% of the cases, a complete response for intravenous CDV was documented and in 88.2% for intravesical CDV. Interestingly, no kidney toxicity was mentioned in intravesical CDV. 9.3% of the intravenously treated patients had renal failure., Conclusion: There is only weak evidence for the use of CDV. The intravesical admission route should be further investigated because of a good toxicity profile., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Although identifying cytological viral inclusions (decoy cells) in the urine is relatively easy, distinguishing between Polyomaviruses BKV and JCV is not possible. Few studies have been published regarding JCV detection in kidney transplant recipients., Objective: To evaluate the incidence of BKV and JCV DNA in archival slides of urine cytospin material from renal transplant patients., Methods: A total of 44 urine specimens were evaluated cytologically for the presence of viral inclusions (decoy cells) and by nested polymerase chain reaction to differentiate between JCV and BKV in DNA isolated from archival slides of urine cytospin material., Results: Of the 44 urine specimen donors, 9 (20.5%) patients had at least 1 sample with alterations suggestive of or compatible with viral infection (decoy cells), and 3 had urine samples with cellular atypias/neoplasias. Additionally, 24/44 (54.5%) patients had PCR-positive DNA for Polyomavirus in at least 1 sample, including 11/44 who were positive for BKV (25%) and 16/44 who were positive for JCV (36.36%), with 3 (6.8%) patients showing viral coinfection. Regarding transplantation time, only JCV was statistically significant (P = .019) for periods longer than 10 years., Conclusions: The results highlight the potential use of archival slides of urine cytospin material to differentiate BKV and JCV and demonstrate the importance of improved JCV detection for later kidney transplant recipients., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Given the contradictory nature of the literature regarding the role of human papillomaviruses and polyomaviruses in the pathogenesis of urothelial bladder cancer (UBC), we sought to investigate the frequency of their involvement in a large cohort of primary UBCs. DNA was extracted from 689 fresh-frozen UBC tissues and screened for the presence of high-risk human papillomavirus (HPV) types 16 and 18 and BKV/JCV genomic DNA by qPCR. In positive cases, viral identity was confirmed by Sanger sequencing and viral gene expression was analysed by RT-PCR or immunohistochemistry. All 689 UBCs were negative for HPV18. One UBC from a female patient with areas of squamous differentiation was positive for HPV16. The qPCR data indicated variable levels of polyomavirus in 49 UBCs. In the UBCs with low C t s we were able to confirm that 23 were BKV and 6 were JCV by Sanger sequencing. Polyomavirus large T antigen expression was low but detectable in 70% of the sequencing-confirmed polyomavirus positive samples. Thus, in United Kingdom patients, the presence of HPV DNA sequences is extremely rare in UBC (<1% of cases). Polyomavirus DNA (predominantly BKV) is more common in UBC, but still only detectable in 7% of cases and in many of these cases at low copy number. We have performed the largest virus screening to date in UBC, finding that HPV16, HPV18 and HPyV are unlikely to be common causative agents in UBC.

There are limited data regarding the association of different levels of BK viremia and BK nephropathy (BKN), and graft outcomes. We studied the BK plasma PCR levels of all kidney transplant recipients (KTR) transplanted at our institution between 01/01/2006 and 06/30/2014. Patients were divided into groups based on their highest BK plasma PCR level within the first year following transplantation: undetectable, low (<1000 copies/mL), moderate (1000-10 000 copies/mL), high (>10 000-100 000 copies/mL), very high (>100 000 copies/mL), and those that had biopsy-proven BKN. There were a total of 1146 KTR during the study period: 813 with undetectable BK levels and 333 with any detectable BK level (87 with low, 79 with moderate, 88 with high, 34 with very high level BK, and 45 that had BKN). Compared to KTR with an undetectable BK level, incidence of mortality, graft failure, rejections,and infections were not significantly different for those with low, moderate, high, or very high BK level. Patients with BKN had a higher rate of infection and higher rates of total graft failure or death-censored graft failure compared to those with undetectable BK levels. BK viremia in the absence of BKN does not significantly increase the risk of rejection, infections, or graft failure compared to an undetectable BK level., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: BK virus (BKV) is a common human polyomavirus and causes latent infection. Especially in immunosuppressive patients, early diagnosis and treatment are very important in reducing the high mortality rate. In this study, we investigated BKV DNA in serum and plasma and urine specimens by real-time polymerase chain reaction (PCR) method in allogeneic hematopoietic stem cell transplantation patients., Materials and Methods: BKV DNA was isolated in QIAsymphony SP/AS (Hilden, Germany) equipment using QIAsymphony DSP Virus/Pathogen Midi Kit, Version 1 (QIAGEN, Hilden, Germany) in urine and serum samples collected from 100 patients post-transplantation. Artus BKV QS-RGQ, V1 (Qiagen, Hilden, Germany) kit for BKV PCR was prepared according to the company recommendations and loaded on Qiagen Rotor Gene (Hilden, Germany). It was evaluated with PCR, and >27 copies/mL was considered as positive., Results: BKV DNA was positive in 57% of the urine specimens obtained; only 25% of the patients were found to have a significant BKV burden in the urine according to the American Society of Transplantation, suggesting a risk of developing nephropathy. Serum samples of the same patients were negative for BKV DNA in 94 cases and they were positive for BKV DNA at interval between 44 and 319 copies/mL in 6 patients, and none of the patients had clinically significant BKV DNA in serum samples., Conclusions: Monitoring the viral load with urine samples were thought to be more convenient for the detection of BKV reactivation in our study., (Copyright © 2018 Elsevier Inc. All rights reserved.)

BK polyomavirus (BKPyV) is an opportunistic infectious pathogen that is associated with hemorrhagic cystitis and nephropathy, mainly in transplant recipients and human immunodeficiency virus 1 (HIV-1) infected patients. However, molecular characterization studies of BKPyV in China are rare. This study was designed to elucidate the prevalence and to determine the main subtypes of BKPyV among HIV-1-infected patients in southeastern China. In addition, the increased incidences for BKPyV reactivation were analyzed. The isolated BKPyV DNA was amplified by polymerase chain reaction (PCR) and the specimen sequences were aligned with the reference sequences for phylogenetic analysis. In this study, BKPyV viruria was detected in 64.2% (88/137) of HIV-1-infected patients. Patients in the BKPyV-positive group were more diverse with respect to gender (P = 0.039) and age (P = 0.023) than their counterparts in the BKPyV-negative group, and they had a higher rate of co-infection with tuberculosis (TB) (P = 0.026). Viruria was more commonly found in patients with CD4 counts <200 cells/mm (72.7%) than in those with CD4 counts ≥200 cells/mm (58.5%) (not significant). All sequenced BKPyV isolates belonged to subtype I (13/32) and IV (19/32). A high prevalence of BKPyV reactivation was discovered in patients with HIV-1 infection. Females and elderly individuals, as well as those with a TB co-infection, appeared more susceptible to BKPyV reactivation in this study. BKPyV viruria was found more often and was associated with lower CD4 counts.

Haemophagocytic lymphohistiocytosis (HLH) is a possibly life-threatening syndrome of immune dysregulation and can be divided into primary (hereditary) and secondary forms (including malignancy-associated HLH (M-HLH)). We retrospectively analysed epidemiological, clinical, virological and laboratory data from patients with M-HLH treated at our department between 1995 and 2014. Out of 1.706 haemato-/oncologic patients treated at our department between 1995 and 2014, we identified 22 (1.29%) patients with secondary HLH (1.3-18.0, median 10.1 years; malignancy induced n = 2; chemotherapy induced n = 20). Patients with acute myeloblastic leukaemia (AML) developed HLH significantly more often than patients with acute lymphoblastic leukaemia (ALL) (10/55, 18.2% vs. 6/148, 4.1%, p = 0.0021). As possible viral triggers, we detected BKV (53.8% of the tested patients), HHV-6 (33.3%), EBV (27.8%), CMV (23.5%), ADV (16.7%) and PVB19 (16.7%) significantly more frequently than in haemato-/oncologic patients without HLH. Despite lacking evidence of concurrent bacterial infection, C-reactive protein (CRP) and procalcitotnin (PCT) were elevated in 94.7 and 77.7% of the patients, respectively. Ferritin and sIL2R were markedly elevated in all patients. HLH-associated mortality significantly (p = 0.0276) decreased from 66.6% (1995-2004) to 6.25% (2005-2014), suggesting improved diagnostic and therapeutic management. Awareness of HLH is important, and fever refractory to antibiotics should prompt to consider this diagnosis. Elevated ferritin and sIL2R seem to be good markers, while inflammatory markers like CRP and PCT are not useful to discriminate viral triggered HLH from severe bacterial infection. Re-/activation of several viruses may play a role as possible trigger.

Background: We sought to determine whether conversion from tacrolimus/mycophenolate mofetil (TAC-MMF) into tacrolimus/mTOR inhibitor (TAC-mTOR) immunosuppression would reduce the incidences of BK and CMV viremia after kidney/pancreas (KP) transplantation., Methods: In this single-center review, the TAC-mTOR cohort (n = 39) was converted at 1 month post-transplant to an mTOR inhibitor and reduced-dose tacrolimus. Outcomes were compared to a cohort of KP recipients (n = 40) maintained on TAC-MMF., Results: At 3 years post-transplant, KP survivals and incidences of kidney/pancreas rejection were equivalent between mTOR and MMF-treated cohorts. (P = ns). BK viremia-free survival was better for the mTOR vs MMF-treated group (P = .004). In multivariate analysis, MMF vs mTOR immunosuppression was an independent risk factor for BK viremia (hazard ratio 12.27, P = .02). Similarly, mTOR-treated recipients displayed better CMV infection-free survival compared to the MMF-treated cohort (P = .01). MMF vs mTOR immunosuppression (hazard ratio 18.77, P = .001) and older recipient age (hazard ratio 1.13 per year, P = .006) were independent risk factors for CMV viremia. Mean estimated GFR and HgbA1c levels were equivalent between groups at 1, 2, and 3 years post-transplantation., Conclusion: Conversion from TAC/MMF into TAC/mTOR immunosuppression after KP transplantation reduced the incidences of BK and CMV viremia with an equivalent risk of acute rejection and similar renal/pancreas function., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Little data exist comparing outcomes following BK nephropathy (BKN) vs acute rejection. We reviewed outcomes among recipients who had a primary diagnosis of biopsy-proven BKN or rejection between 1 and 18 months post-transplant. There were 96 cases of BKN and 256 cases of rejections. We compared outcomes of BKN with all rejection combined and also with cellular rejection. Seven of 256 (2.7%) patients developed BKN after treatment of rejection. Conversely, 8 of 96 (8.3%) developed rejection after BKN. The eGFR at time of diagnosis in the BKN group (33.7 ± 12.6) was lower than the rejection group (44.8 ± 23.3, P < .001). The eGFR at 6 months after diagnosis of BKN was 32.7 ± 14.9 and for rejection was 48.8 ± 20.7 (P ≤ .001). The mean eGFR at 3 years postdiagnosis was 41.6 ± 18.5 in BKN and 53 ± 21.3 for rejection (P = .001). The graft failure incidence rates were similar between 2 groups. A similar pattern was observed comparing BKN with cellular rejection. While the difference in rate of graft loss between BKN and rejection did not reach statistical significance, kidney function up to 3 years after diagnosis was worse for BKN than for rejection, suggesting that BKN is at least as damaging to kidneys as rejection., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

We aim to identify the key protein interaction networks and implicated pathways of BK virus nephropathy (BKVN) via bioinformatic methods. The microarray data GSE75693 of 30 patients with stable kidney transplantation and 15 with BKVN were downloaded and analyzed by using the limma package to identify differentially expressed genes (DEGs). Then the gene ontology (GO) functional enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were done to investigate the molecular function (MF), biological process (BP), cellular components (CC) and pathways of DEGs. Finally, protein-protein interactions (PPIs) were constructed, and the hub proteins were  identified. As a result, 249 up-regulated genes and 253 down-regulated genes of BKVN patients were selected based on criteria of P > 0.01 and fold change >2.0. GO and KEGG showed that DEGs were mainly located in nucleus and cytosol, and were implicated in the immune responses. In the PPI analysis, 26 up-regulated and 8 down-regulated proteins composed the pivotal interaction network. CXCL10, EGF and STAT1 were identified as hub proteins in BKVN. In conclusion, CXCL10, EGF and STAT1 may induce kidney injuries by promoting inflammation and prohibiting reparation of tissue damage in BKVN.

Viruses including Epstein-Barr virus (EBV), JCV and BKV have been reported to be associated with some cancers. The association of these viruses with colorectal cancers remains controversial. Our objective was to investigate their infections association with adenocarcinoma and adenomatous polyps of the colon. Totally, 210 paraffin-embedded tissue specimens encompassing 70 colorectal adenocarcinoma, 70 colorectal adenomatous and 70 colorectal normal tissues were included. The total DNA was extracted, then qualified samples introduced to polymerase chain reaction (PCR). The EBV, JCV and BKV genome sequences were detected using specific primers by 3 different in-house PCR assays. Out of 210 subjects, 98 cases were female and the rest were male. The mean age of the participants was 52 ± 1.64 years. EBV and JCV DNA was detected just in one (1.42%) out of seventy adenocarcinoma colorectal tissues. All adenomatous polyp and normal colorectal tissues were negative for EBV and JCV DNA sequences. Moreover, all the patients and healthy subjects were negative for BKV DNA sequences. The results suggested that EBV and JCV genomes were not detectable in the colorectal tissue of patients with colorectal cancer in our population. Hence, BKV might not be necessitated for the development of colorectal cancer. The findings merit more investigations.

Background and Objectives: The risk of de novo donor-specific antibody (dnDSA) development following BK viremia (BKV) or nephropathy (BKN) after kidney transplant remains unclear. We aimed to evaluate the relationships among dnDSA, BKV (BK blood PCR > 15 000 copies), BKN, antibody-mediated rejection (AMR), and allograft loss., Patients and Methods: We performed a retrospective cohort study of 904 solitary kidney transplant recipients transplanted between 10/2007 and 5/2014. Cox proportional hazards regression with time-dependent covariates were used to assess the relationships among BKN, isolated BKV, dnDSA, and the subsequent risk of AMR and allograft loss., Results: In multivariate analysis, we observed that BKN, but not BKV was a risk factor for dnDSA (HR, 3.18, P = .008). Of the patients with BK nephropathy, 14.0% (6/43) developed dnDSA, which occurred within 14 months of BK diagnosis. DnDSA in this setting remains a risk factor for subsequent AMR (HR 4.75, P = .0001) and allograft loss (HR 2.63, P = .018)., Conclusions: BKN is an independent risk factor for development of dnDSA. Improved understanding of the characteristics of patients with BKN who are at highest risk for development of dnDSA would be valuable to customize immunosuppression reduction in this population., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

To identify decoy cells, cytological examination was performed in urine cytospin slides. Decoy cells are related to Polyomaviruses (JC virus [JCV] and BK virus [BKV]), which are recognized worldwide due to potential infection and morbidity in kidney transplant recipients. Cytologically, it is difficult to evaluate the cytopathic effect of JCV and BKV in urine of patients with urothelial neoplasia. For this reason, there is a need for molecular approaches. To evaluate the incidence of BKV and JCV DNA in archival slides of urine cytospin material with benign and malignant characteristics. A total of 176 urine specimens were used for cytological examination of neoplastic or decoy cells. The samples were analyzed for the presence of JCV and BKV, by polymerase chain reaction (PCR) in DNA Isolated from archival slides of urine cytospin material. A typical samples (n = 48) were compared with the remaining 128 samples without atypia/neoplasia for the presence of JCV or BKV DNA. A statistically nonsignificant result was observed correlating the presence of JCV or BKV. The results show that DNA Isolated from archival slides of urine cytospin material can be used for detection of BKV and JCV., (© 2017 Wiley Periodicals, Inc.)

Background: Urinary CXC chemokine ligand 10 (CXCL10) is a promising biomarker for subclinical tubulointerstitial inflammation, but limited data exist regarding its correlation with (micro)vascular inflammation. Furthermore, no study has evaluated whether concomitant serum CXCL10 improves the discrimination for (micro)vascular inflammation., Methods: We investigated whether serum/urinary CXCL10 reflect subclinical inflammation within different renal compartments. Patients (n = 107) with 107 surveillance biopsies were classified as: normal histology (n = 47), normal histology with polyomavirus BK (BKV) or cytomegalovirus (CMV) viremia (n = 17), moderate-severe tubulointerstitial inflammation (tubulitis ≥2, n = 18), pure microvascular inflammation (n = 15), and isolated v lesions (n = 10). Serum and urinary CXCL10 Enzyme-linked Immunosorbent Assay was performed. An independent validation set was evaluated for urine CXCL10: normal histology (n = 14), normal histology with BKV or CMV viremia (n = 19), tubulitis ≥2 (n = 15), pure microvascular inflammation (n = 41), and isolated v lesions (n = 14)., Results: Elevated urinary CXCL10 reflected inflammation within the tubulointerstitial (urinary CXCL10/creatinine, 1.23 ng/mmol vs 0.46 ng/mmol; P = 0.02; area under the curve, 0.69; P = 0.001) and microvascular compartments (urinary CXCL10/creatinine, 1.72 ng/mmol vs 0.46 ng/mmol; P = 0.03; area under the curve, 0.69; P = 0.02) compared to normal histology. Intriguingly, urinary CXCL10 was predominantly elevated with peritubular capillaritis, but not glomerulitis (P = 0.04). Furthermore, urinary CXCL10 corresponded with BKV, but not CMV viremia (P = 0.02). These urine CXCL10 findings were confirmed in the independent validation set. Finally, serum CXCL10 was elevated with BKV and CMV viremia but was not associated with microvascular or vascular inflammation (P ≥ 0.19)., Conclusions: Urinary CXCL10 reflects subclinical inflammation within the tubulointerstitial and peritubular capillary spaces, but not the vascular/systemic compartments; this was consistent with BKV (tubulointerstitial) and CMV viremia (systemic). Serum CXCL10 was not a useful marker for (micro)vascular inflammation.