Avian Polyomavirus Among Psittacine Birds in Iran: Molecular Detection Rate and Associated Risk Factors

Avian polyomavirus (APV) infection causes various health problems in psittacine species, including death. The present study was conducted to investigate the prevalence of APV among psittacine birds in Iran. We also aimed to evaluate the impact of age, sex, species, season, and origin of the birds on the prevalence of APV. This study investigated the presence of APV among 1050 individual birds from 7 psittacine species over a 1-year period in Iran, namely, green-cheeked parakeets (Pyrrhura molinae), rosy-faced lovebirds (Agapornis roseicollis), monk parakeets (Myiopsitta monachus), sun conures (Aratinga solstitialis), Senegal parrots (Poicephalus senegalus), cockatiels (Nymphicus hollandicus), and grey parrots (Psittacus erithacus). The overall prevalence of APV in all studied species was 25% (263/1050, 95% confidence interval [CI]: 22.5-27.8). Results of the study showed that age and the season of the year were 2 important determinant factors in the prevalence of APV in psittacine birds. Young psittacine birds <6 months old were 2.94 (95% CI: 1.19-7.27) times more likely to be infected with APV than birds >1 year old, and there was a significant interaction between season and species in the multivariate analysis. In the winter season, rosy-faced lovebirds and green-cheeked parakeets were 15.6 (95% CI: 4.20-57.95) and 4.76 (95% CI: 1.4-16.21) times more likely to be infected with APV than in other seasons, respectively. This is the first report on the detection rate of APV in psittacine birds in Iran.

High grade urothelial carcinoma in kidney transplant patients with a history of BK viremia - Just a coincidence?

INTRODUCTION

Kidney transplant recipients (KTR) have a three-to-four-fold increased risk of developing urothelial carcinoma (UC) compared to the general population. BK polyoma virus (BKV) infection is known to affect approximately 15% of KTR. In vitro models support a potential pathogenic role for BKV in the development of UC. We describe a series of UC in kidney transplant recipients.

METHODS

Electronic patient records were searched to identify KTR with UC who had undergone kidney only or simultaneous kidney and pancreas transplantation in a single UK center between 2009 and 2015. Where available, stored pathological samples were retrieved, re-examined and stained for SV40 as a marker of BKV using standard staining protocols for kidney biopsy samples.

RESULTS

Fourteen KTR had developed UC post-transplant. Of these, 10 KTR had a history of BKV infection post-transplant. Six of these 10 KTR developed a rare micropapillary tumor subtype of UC which is typically only found in <1% of UC cases. All six micropapillary tumor samples stained positive for SV40, including samples from metastases. Three tumor samples were available from the four KTR with no history of BKV infection and were not micropapillary subtype and were negative for SV40. Three micropapillary tumors from immunocompetent patients were examined as controls and were negative for SV40.

CONCLUSIONS

These findings would support a pathogenic role for BK virus in the development of rare micropapillary subtype urothelial tumors in the kidney transplant population.

Evolutionary Insight into the Association between New Jersey Polyomavirus and Humans

Advances in viral discovery techniques have led to the identification of numerous novel viruses in human samples. However, the low prevalence of certain viruses in humans raises doubts about their association with our species. To ascertain the authenticity of a virus as a genuine human-infecting agent, it can be useful to investigate the diversification of its lineage within hominines, the group encompassing humans and African great apes. Building upon this rationale, we examined the case of the New Jersey polyomavirus (NJPyV; Alphapolyomavirus terdecihominis), which has only been detected in a single patient thus far. In this study, we obtained and analyzed sequences from closely related viruses infecting all African great ape species. We show that NJPyV nests within the diversity of these viruses and that its lineage placement is compatible with an ancient origin in humans, despite its apparent rarity in human populations.

Risk factors for BK virus-associated hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation: A systematic review and meta-analysis

OBJECTIVE AND BACKGROUND

BK virus-associated hemorrhagic cystitis (BKV-HC) is an intractable complication leading to higher mortality and prolonged hospitalization among allogeneic hematopoietic stem cell transplantation (allo-HCT) recipients. Therefore, identifying the potential risk factors of BKV-HC after allo-HCT is crucial to improve prognosis and for early prevention. However, the risk factors for BKV-HC remain debatable. Therefore, we conducted a systematic review and meta-analysis to identify the risk factors for BKV-HC, for early prevention of the occurrence of BKV-HC and to improve the quality of life and prognosis of allo-HCT recipients.

METHODS

We searched relevant studies from PubMed, EMBASE, and the Cochrane Library up to February 2023. The odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) of all risk factors were calculated to evaluate their effects on the occurrence of BKV-HC.

RESULTS

Overall, 11 studies involving 2556 allo-HCT recipients were included in this meta-analysis. All included studies were retrospective and published between 2013 and 2022. We found that male sex (OR = 1.32; 95% CI, 1.07-1.62; p = .009, I2  = 34%), haploidentical donor (OR = 1.84; 95% CI, 1.18-2.87; p = .007, I2  = 23%), myeloablative conditioning (OR = 1.76; 95% CI, 1.36-2.28; p < .0001, I2  = 45%), acute graft versus host disease (aGVHD) (OR = 2.73; 95% CI, 2.02-3.69; p < .0001, I2  = 46%), chronic graft versus host disease (cGVHD) (OR = 1.71; 95% CI, 1.12-2.60; p = .01, I2  = 0%), and cytomegalovirus (CMV) reactivation (OR = 3.13; 95% CI, 1.12-8.78; p = .03, I2  = 79%) were significantly associated with BKV-HC in the univariable analysis.

CONCLUSIONS

Our meta-analysis indicated that male sex, haploidentical donor, myeloablative conditioning, aGVHD, cGVHD, and CMV reactivation were potential risk factors for BKV-HC.

BK polyomavirus DNAemia in pancreas transplant recipients compared to pancreas-kidney recipients

BACKGROUND

BK polyomavirus (BKV) infection is a common complication of kidney transplantation. While BKV has been described in non-kidney transplant recipients, data are limited regarding its epidemiology and outcomes in pancreas transplant recipients.

METHODS

We conducted a retrospective cohort study of adults who underwent pancreas transplantation from 2010-2020. The primary outcome was BKV DNAemia. Secondary outcomes were estimated glomerular filtration rate (eGFR) reduction by 30%, eGFR < 30 mL/min/1.73 m2 , endstage kidney disease, and pancreas allograft failure. Cox regression with time-dependent variables was utilized.

RESULTS

Four hundred and sixty-six patients were analyzed, including 74, 46, and 346 with pancreas transplant alone (PTA), pancreas-after-kidney, or simultaneous pancreas-kidney transplants, respectively. PTA recipients experienced a lower incidence of BKV DNAemia (8.8% vs. 32.9%; p < .001) and shorter duration of DNAemia (median 28.0 vs. 84.5 days). No PTA recipients with BKV DNAemia underwent kidney biopsy or developed endstage kidney disease. Lymphopenia, non-PTA transplantation, and older age were associated with BKV DNAemia, which itself was associated with pancreas allograft failure (adjusted hazard ratio 2.14, 95% confidence interval 1.27-3.60; p = .004). Among PTA recipients, BKV DNAemia was not associated with eGFR reduction or eGFR < 30 mL/min/1.73 m2 .

CONCLUSIONS

BKV DNAemia was common among PTA recipients, though lower than a comparable group of pancreas-kidney recipients. However, BKV DNAemia was not associated with adverse native kidney outcomes and no PTA recipients developed endstage kidney disease. Conversely, BKV DNAemia was associated with pancreas allograft failure. Further studies are needed to estimate the rate of BKV nephropathy in this population, and further evaluate long-term kidney outcomes.

[Risk factors for hemorrhagic cystitis in children with β-thalassemia major after allogeneic hematopoietic stem cell transplantation]

OBJECTIVES

To explore the risk factors for hemorrhagic cystitis (HC) in children with β-thalassemia major (TM) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT).

METHODS

A retrospective analysis was conducted on clinical data of 247 children with TM who underwent allo-HSCT at Shenzhen Children's Hospital from January 2021 to November 2022. The children were divided into an HC group (91 cases) and a non-HC group (156 cases) based on whether HC occurred after operation. Multivariable logistic regression analysis was used to explore the risk factors for HC, and the receiver operating characteristic curve was used to analyze the predictive efficacy of related factors for HC.

RESULTS

Among the 247 TM patients who underwent allo-HSCT, the incidence of HC was 36.8% (91/247). Univariate analysis showed age, incompatible blood types between donors and recipients, occurrence of acute graft-versus-host disease (aGVHD), positive urine BK virus deoxyribonucleic acid (BKV-DNA), and ≥2 viral infections were associated with the development of HC after allo-HSCT (P<0.05). Multivariable analysis revealed that incompatible blood types between donors and recipients (OR=3.171, 95%CI: 1.538-6.539), occurrence of aGVHD (OR=2.581, 95%CI: 1.125-5.918), and positive urine BKV-DNA (OR=21.878, 95%CI: 9.633-49.687) were independent risk factors for HC in children with TM who underwent allo-HSCT. The receiver operating characteristic curve analysis showed that positive urine BKV-DNA alone or in combination with two other risk factors (occurrence of aGVHD, incompatible blood types between donors and recipients) had a certain accuracy in predicting the development of HC after allo-HSCT (area under the curve >0.8, P<0.05).

CONCLUSIONS

Incompatible blood types between donors and recipients, occurrence of aGVHD, and positive urine BKV-DNA are risk factors for HC after allo-HSCT in children with TM. Regular monitoring of urine BKV-DNA has a positive significance for early diagnosis and treatment of HC.

The Relationship between Acute Rejection, Hemoglobin Level, and BK Virus Infection Among Renal Transplant Recipients

BACKGROUND

This study aimed to explore the risk factors for BK virus (BKV) infection in renal transplant recipients (RTRs) routinely treated with tacrolimus.

METHODS

Forty-two cases with BKV infections and 51 patients without BKV infections were enrolled in the study. Eighty-seven healthy individuals and 77 patients undergoing dialysis were randomly included as controls. A logistic regression model was used to analyze potential variables in order to evaluate factors related to BKV infection in the renal transplant recipients.

RESULTS

The number of individuals with acute rejection in BKV positive RTRs is significantly higher than that in BKV negative RTRs. Hemoglobin levels in BKV positive RTRs were significantly lower than those in BKV negative RTRs (109.61 ± 20.11 vs. 130.16 ± 26.297, p < 0.001). There was a positive correlation between tacrolimus levels and hemoglobin concentration in RTRs (r = 0.329, p = 0.023). The results of a multivariate regression analysis indicated that a history of acute rejection (OR = 4.157, p = 0.031) and low hemoglobin (OR = 0.963, p < 0.001) were risk factors for BKV infection.

CONCLUSIONS

Acute rejection and low hemoglobin were risk factors for BKV infection after renal transplantation.

Human polyomavirus 9 as a potential threat in kidney transplant recipients; lessons from BKPyV

As a therapeutic method, kidney transplantation significantly improved the life quality and prognosis of patients with the end-stage renal disease. Since a key element in stable kidney transplantation is continuous therapy with immunosuppressive agents, an inhibited immune response makes patients vulnerable to opportunistic viral and bacterial infections. Polyomavirus (PyV), from the Polyomaviridae family, includes a well-known BK virus (BKPyV) and less publicized human polyomavirus 9 (HPyV9). Both these viruses may inflict significant damage to kidney transplants because of their high prevalence and pathogenesis. While a great body of knowledge was accumulated about the BKPyV-caused nephropathy, much less information is about the potential threat from the HPyV9-caused damage to kidney transplants. The current review provides a glimpse of general information about the PyV-associated nephropathy with a special focus on the role of the HPyV9 in pathogenesis of nephropathy in kidney transplants.

Increased CMV disease and "severe" BK viremia with belatacept vs. sirolimus three-drug maintenance immunosuppression

OBJECTIVES

Belatacept may provide benefit in delayed graft function, but its association with infectious complications is understudied. We aim to assess the incidence of CMV and BK viremia in patients treated with sirolimus or belatacept as part of a three-drug immunosuppression regimen after kidney transplantation.

MATERIALS AND METHODS

Kidney transplant recipients from 01/01/2015 to 10/01/2021 were retrospectively reviewed. Maintenance immunosuppression was either tacrolimus, mycophenolate and sirolimus (B0) or tacrolimus, mycophenolate, and belatacept (5.0 mg/kg monthly) (B1). Primary outcomes of interest were BK and CMV viremia which were followed until the end of the study period. Secondary outcomes included graft function (serum creatinine, eGFR) and acute rejection through 12 months.

RESULTS

Belatacept was initiated in patients with a higher mean kidney donor profile index (B0:0.36 vs. B1:0.44, p = .02) with more delayed graft function (B0:6.1% vs. B1:26.1%, p < .001). Belatacept therapy was associated with more "severe" CMV viremia >25,000 copies/mL (B0:1.2% vs. B1:5.9%, p = .016) and CMV disease (B0:0.41% vs. B1:4.2%, p = .015). However, there was no difference in the overall incidence of CMV viremia >200 IU/mL (B0:9.4% vs. B1:13.5%, p = .28). There was no difference in the incidence of BK viremia >200 IU/mL (B0:29.7% vs. B1:31.1%, p = .78) or BK-associated nephropathy (B0:2.4% vs. B1:1.7%, p = .58), but belatacept was associated with "severe" BK viremia, defined as >10,000 IU/mL (B0:13.0% vs. B1:21.8%, p = .03). The mean serum Cr was significantly higher with belatacept therapy at 1-year follow up (B0:1.24 mg/dL vs. B1:1.43 mg/dL, p = .003). Biopsy-proven acute rejection (B0:1.2% vs. B1:2.6%, p = .35) and graft loss (B0:1.2% vs. B1:0.84%, p = .81) were comparable at 12 months.

CONCLUSIONS

Belatacept therapy was associated with an increased risk of CMV disease and "severe" CMV and BK viremia. However, this regimen did not increase the overall incidence of infection and facilitated comparable acute rejection and graft loss at 12-month follow up.

Infection by human polyomaviruses JCPyV and BKPyV in blood donors of Argentina

BACKGROUND AND OBJECTIVES

A spectrum of blood-borne infectious agents may be transmitted through transfusion of blood components from asymptomatic donors. Despite the persistence of polyomaviruses in blood cells, no studies have been conducted in Argentina to assess the risk of transfusion infection.

MATERIALS AND METHODS

We investigated BKPyV and JCPyV in 720 blood donors, using polymerase chain reaction (PCR) for a region of T antigen common to both viruses. Positive T-antigen samples were subjected to two additional PCR assays targeting the VP1 region. Viral genotypes were characterized by phylogenetic analysis.

RESULTS

Polyomaviruses were detected in 1.25% (9/720) of the blood samples selected; JCPyV was identified in 0.97% (7/720) and BKPyV in 0.28% (2/720) of them. Phylogenetic analysis showed that the JCPyV sequences clustered with 2A genotype and Ia of BKPyV.

CONCLUSION

This study describes for the first time the prevalence of polyomavirus DNA in blood donors of Córdoba, Argentina. The polyomavirus DNAemia in healthy populations suggests that those viruses are present in blood components eligible for transfusion. Therefore, the epidemiological surveillance of polyomavirus in blood banks might be incorporated into haemovigilance programmes, to determine the infectious risk and implement newer interventions to ensure the safety of blood supplies, if required.

Evidence for virus-mediated oncogenesis in bladder cancers arising in solid organ transplant recipients

A small percentage of bladder cancers in the general population have been found to harbor DNA viruses. In contrast, up to 25% of tumors of solid organ transplant recipients, who are at an increased risk of developing bladder cancer and have an overall poorer outcomes, harbor BK polyomavirus (BKPyV). To better understand the biology of the tumors and the mechanisms of carcinogenesis from potential oncoviruses, we performed whole genome and transcriptome sequencing on bladder cancer specimens from 43 transplant patients. Nearly half of the tumors from this patient population contained viral sequences. The most common were from BKPyV (N=9, 21%), JC polyomavirus (N=7, 16%), carcinogenic human papillomaviruses (N=3, 7%), and torque teno viruses (N=5, 12%). Immunohistochemistry revealed variable Large T antigen expression in BKPyV-positive tumors ranging from 100% positive staining of tumor tissue to less than 1%. In most cases of BKPyV-positive tumors, the viral genome appeared to be clonally integrated into the host chromosome consistent with microhomology-mediated end joining and coincided with focal amplifications of the tumor genome similar to other virus-mediated cancers. Significant changes in host gene expression consistent with the functions of BKPyV Large T antigen were also observed in these tumors. Lastly, we identified four mutation signatures in our cases, with those attributable to APOBEC3 and SBS5 being the most abundant. Mutation signatures associated with an antiviral drug, ganciclovir, and aristolochic acid, a nephrotoxic compound found in some herbal medicines, were also observed. The results suggest multiple pathways to carcinogenesis in solid organ transplant recipients with a large fraction being virus-associated.

Merkel cell polyomavirus (MCPyV) DNA prevalence in Brazilian blood donors

Merkel cell polyomavirus (MCPyV) is an oncogenic virus that has been etiologically linked to Merkel cell carcinoma. Low levels of MCPyV DNA have been detected in blood donors with unclear impact on transfusion. The prevalence of MCPyV DNA in Brazilian blood donors is unclear. Therefore, the objective of this study was to evaluate the MCPyV DNA prevalence among Brazilian blood donors. We examined the presence of MCPyV DNA by real-time PCR (qPCR) in a total of 450 serum samples obtained from blood donors from three Brazilian regions (North, Central-West and South). The overall estimated MCPyV DNA prevalence was 1.1% (CI = 95%, 0.16-2.06%). Divided by region, in North Brazil (city of Macapa, state of Amapá) and South Brazil (city of Santa Maria, state of Rio Grande do Sul), the MCPyV prevalence was the same: 1.33% (CI = 95%, range 0.0-3.14%). In Central-West Brazil (city of Brasilia), the MCPyV prevalence was 0.6% (CI = 95%, 0.0-1.96%). All MCPyV positive samples showed a high cycle threshold (median Ct = 35.5), most probably related to the low viral load. More studies are necessary to unveil the impact of this oncogenic virus on transfusion medicine and if such exists, especially in regards of its infectivity and transmission potential.

Seroprevalence of Four Polyomaviruses Linked to Dermatological Diseases: New Findings and a Comprehensive Analysis

Our aim was to study the seroprevalence of human polyomaviruses (HPyV) linked to skin diseases. A total of 552 serum samples were analysed by the enzyme-linked immunosorbent assay to detect IgG antibodies against Merkel cell polyomavirus (MCPyV), HPyV6, HPyV7 and Trichodysplasia spinulosa-associated polyomavirus (TSPyV) using recombinant major capsid proteins of these viruses. The individuals (age 0.8−85 years, median 33) were sorted into seven age groups: <6, 6−10, 10−14, 14−21, 21−40, 40−60 and >60 years. The adulthood seroprevalence was 69.3%, 87.7%, 83.8% and 85% for MCPyV, HPyV6, HPyV7 and TSPyV, respectively. For all four polyomaviruses, there was increasing seropositivity with age until reaching the adulthood level. There was a significant increase in seroreactivity for those age groups in which the rate of already-infected individuals also showed significant differences. The adulthood seropositvity was relatively stable with ageing, except for TSPyV, for which elevated seropositivity was observed for the elderly (>60 years) age group. Since seroepidemiological data have been published with wide ranges for all the viruses studied, we performed a comprehensive analysis comparing the published age-specific seropositivities to our data. Although the cohorts, methods and even the antigens were variable among the studies, there were similar results for all studied polyomaviruses. For MCPyV, geographically distinct genotypes might exist, which might also result in the differences in the seroprevalence data. Additional studies with comparable study groups and methods are required to clarify whether there are geographical differences.

Natural History of Incident and Persistent Cutaneous Human Papillomavirus and Human Polyomavirus Infections

BACKGROUND

Cutaneous human papillomaviruses (cuHPV) and polyomaviruses (HPyV) have been implicated in skin cancers; however, interpretation of findings across studies is complicated by limited understanding of the natural history of these infections across normal tissue types.

METHODS

In total, 675 eyebrow hair (EBH) and skin swab (SSW) samples were collected from 71 skin cancer screening patients every 6 months over 2 years and measured for presence of β-HPV, γ-HPV, and HPyV. Incidence, persistence, and clearance of cuHPV/HPyV were estimated, and risk factors associated with infection were examined.

RESULTS

Prevalence, incidence, and persistence of β-HPV, γ-HPV, and HPyV were consistently higher in SSW than in EBH, with types 5, 24, 49, 76 and Merkel cell polyomavirus (MCPyV) having incidence rates greater than 20 per 1000 person-months. Prevalent γ-HPV EBH infections persisted more often in women (P = .024), incident β-HPV EBH infections persisted less often among individuals with history of blistering sunburn (P = .019), and prevalent MCPyV SSW infections persisted more often in those with a history of skin cancer (P = .033).

CONCLUSIONS

Incidence and persistence of cuHPV/HPyV were observed in SSW and EBH; however, none of the risk factors examined were commonly associated with cuHPV/HPyV infections across normal tissue types.

Trichodysplasia Spinulosa Polyomavirus Endothelial Infection, California, USA

We describe 3 patients in California, USA, with trichodysplasia spinulosa polyomavirus (TSPyV) infection of endothelium after steroid administration. We detected TSPyV RNA in tissue specimens by in situ hybridization, which revealed localization to endothelial cells. These cases suggest that diseases associated with endothelial inflammation could be associated with TSPyV infection.

WU Polyomavirus Infection in Children With Acute Lower Respiratory Tract Infections in China, 2017 to 2019: Case Reports and Multicentre Epidemiological Survey

WU polyomavirus (WUPyV) is a novel member of the family Polyomaviridae recently detected in respiratory tract specimens. So far, it has not been proven whether WUPyV is a real causative agent for respiratory diseases. In this study, we described two patients with fatal infection who had WUPyV detected in their nasopharyngeal swabs. Furthermore, we conducted a multicentre study in six hospitals from different districts of China. WUPyV was detected by real-time polymerase chain reaction assays, and the clinical and molecular epidemiological characteristics of WUPyV strains among hospitalized children with acute lower respiratory tract infections all around China from 2017 to 2019 were analysed. Two complete WUPyV genome sequences were assembled from fatal patients’ airway specimens. Phylogenetic tree analysis revealed that they were most closely related to strains derived from Fujian and Chongqing, China, in 2008 and 2013, respectively. In 2017–2019, a total of 1,812 samples from children with acute lower respiratory tract infections were detected for WUPyV, of which 11 (0.6%) were positive. Children aged ≤5 were more susceptible to WUPyV infection. A total of 81.8% of WUPyV-positive patients were coinfected with other viruses, of which rhinovirus enjoyed the highest frequency. The main clinical symptoms of infected patients include fever, coughing and sputum expectoration. Most patients were diagnosed with pneumonia, followed by bronchial surgery. Three patients manifested severe infection, and all patients improved and were discharged. Our results show that WUPyV persistently circulates in China. Further investigations on the clinical role and pathogenicity of WUPyV are necessary.

Polyoma BK Virus in Kidney Transplant Recipients: Screening, Monitoring, and Management

Polyomavirus BK virus (BKPyV) infection is an important complication of kidney transplantation and allograft failure. The prevalence of viremia is 10%-15%, compared with BK-associated nephropathy (BKPyVAN) at 3%-5%. Given that there are no effective antiviral prophylaxis or treatment strategies for BKPyVAN, active screening to detect BKPyV viremia is recommended, particularly during the early posttransplant period. Immunosuppression reduction to allow viral clearance may avoid progression to severe and irreversible allograft damage. The frequency and duration of screening are highly variable between transplant centers because the evidence is reliant largely on observational data. While the primary treatment goals center on achieving viral clearance through immunosuppression reduction, prevention of subsequent acute rejection, premature graft loss, and return to dialysis remain as major challenges. Treatment strategies for BKPyV infection should be individualized to the recipient's underlying immunological risk and severity of the allograft infection. Efficacy data for adjuvant therapies including intravenous immunoglobulin and cidofovir are sparse. Future well-powered and high-quality randomized controlled trials are needed to inform evidence-based clinical practice for the management of BKPy infection.

Diagnostic options for human polyomaviruses in clinical practice

The members of the viral family Polyomavirae are widespread in the human population. According to serological studies, almost all adults are infected with at least one of this group of viruses. The primary infection usually occurs in childhood without any clinical signs, and after the primary infection, the viruses establish a persistent infection accompanied by occasional reactivation and shedding of the virus. These viruses often reactivate in immunosuppressed individuals, but only in a minority of these patients, the reactivation results in disease development. This biological property of human polyomaviruses makes laboratory diagnosis considerably difficult. The paper provides an overview of methods for diagnosing human polyomaviruses, which are commonly used for screening, and methods that are still validated by research but have the potential to improve detection and to identify patients at risk of developing diseases associated with polyomavirus infection.

The case for BK polyomavirus as a cause of bladder cancer

In 2014, the International Agency for Research on Cancer judged Merkel cell polyomavirus (MCPyV) to be a probable human carcinogen. BK polyomavirus (BKPyV, a distant cousin of MCPyV) was ruled a possible carcinogen. In this review, we argue that it has recently become reasonable to view both of these viruses as known human carcinogens. In particular, several complementary lines of evidence support a causal role for BKPyV in the development of bladder carcinomas affecting organ transplant patients. The expansion of inexpensive deep sequencing has opened new approaches to investigating the important question of whether BKPyV causes urinary tract cancers in the general population.

Identification of BK Virus Genotypes in Recipients of Renal Transplant in Vietnam

OBJECTIVES

This study aims to investigate the prevalence and distribution of BK polyomavirus (BKV) genotypes in recipients of renal transplant in Vietnam.

METHODS

One hundred six patients who underwent renal transplantation were included in this study. These patients were from the Department of Nephrology, Military Hospital 103, Vietnam Military Medical University. Quantification and genotyping of the BK virus was performed using in-house molecular methods from urine and plasma samples.

RESULTS

BKV infection was detected in 82 patients (77.4%), including 58 patients who had the presence of both BK viremia and BK viruria, and 24 patients (22.60%) with BKV positive findings in the urine alone. Particularly, 16 patients (15.09%) had high BK viremia >10⁴ copies/mL and 20 patients (18.9%) had BK viruria >10⁷ copies/mL. BK virus nephropathy (BKVN) was confirmed in 6 patients (5.66%) by immunohistochemistry examination. Genotyping of BKV was performed successfully in 50 out of the 82 patients, with 36 out of 50 (72%) belonging to the BKV-I subtype and 14 out of 50 (28%) belonging to the BKV-IV subtype; no cases of genotypes II or III were observed. Using phylogenetic analysis of the subgroups, the BKV-I/b-1 subtype was found the predominant subgroup (100%), whereas BKV-IV included 21.43% of IV/a-1, 6.67% of IV/a-2, and 50% of IV/c-1, respectively. There remain 3 cases of BKV-IV (21.43%) that could not be categorized into any subgroups. In the 6 patients diagnosed BKVN, 5 of them were infected with subgroup I/b-1 (83.3%) and 1 patient was infected with subgroup IV/c-1 (16.7%). No significant difference between BKV genotypes was observed in relation to age, sex, HLA mismatch, viral load, BKVN, and immunosuppressive therapy.

CONCLUSIONS

This research indicated a high prevalence of BKV infection and BKV-I was predominant, followed by BKV-IV among recipients of renal transplant in Vietnam.

BK viremia and nephropathy in pediatric renal transplant recipients

The renal survival rate of pediatric renal transplant recipients (pRTR) has improved with the use of modern immunosuppressive agents; however, the incidence of post-transplantation viral infection has increased. This study investigated the incidence of BK viremia and BK viral-associated nephropathy (BKVAN) in pRTR. One-hundred-and-thirty-four pRTR were divided into two groups: group 1 (n = 20, 14.9%) comprised those who were prospectively followed with longitudinal analyses after renal transplantation in the time period from May 2007 to June 2008, while group 2 (n = 114, 85.1%) cross-sectional study of those who were transplanted from January 1994 to April 2007. The mean ages at transplantation in groups 1 and 2 were 10.6 ± 4.7 years and 7.8 ± 4.5 years, respectively. BK viremia was detected in four (20.0%) patients in group 1, and seven (6.1%) in group 2 (P = 0.04), with increased incidence associated with induction therapy. The median time to detection of BK viremia after transplantation was 44 days in group 1 and 142 days in group 2. BKVAN was diagnosed in three patients (two in group 1 and one in group 2). All three patients diagnosed with BKVAN were receiving tacrolimus, mycophenolate mofetil, and corticosteroids as maintenance immunosuppression. Reducing immunosuppression resulted in reduced BK viremia. Monitoring for BK viremia and BKVAN is important in pRTR being treated with the current immunosuppressive regimen. The first line of treatment for BK viremia remains careful reduction of immunosuppression and close monitoring of renal allograft function.

An open-label, randomized trial indicates that everolimus with tacrolimus or cyclosporine is comparable to standard immunosuppression in de novo kidney transplant patients

This is a randomized trial (ATHENA study) in de novo kidney transplant patients to compare everolimus versus mycophenolic acid (MPA) with similar tacrolimus exposure in both groups, or everolimus with concomitant tacrolimus or cyclosporine (CsA), in an unselected population. In this 12-month, multicenter, open-label study, de novo kidney transplant recipients were randomized to everolimus with tacrolimus (EVR/TAC), everolimus with CsA (EVR/CsA) or MPA with tacrolimus (MPA/TAC), with similar tacrolimus exposure in both groups. Non-inferiority of the primary end point (estimated glomerular filtration rate [eGFR] at month 12), assessed in the per-protocol population of 338 patients, was not shown for EVR/TAC or EVR/CsA versus MPA/TAC. In 123 patients with TAC levels within the protocol-specified range, eGFR outcomes were comparable between groups. The mean increase in eGFR during months 1 to 12 post-transplant, analyzed post hoc, was similar with EVR/TAC or EVR/CsA versus MPA/TAC. The incidence of treatment failure (biopsy proven acute rejection, graft loss or death) was not significant for EVR/TAC but significant for EVR/CsA versus MPA/TAC. Most biopsy-proven acute rejection events in this study were graded mild (BANFF IA). There were no differences in proteinuria between groups. Cytomegalovirus and BK virus infection were significantly more frequent with MPA/TAC. Thus, everolimus with TAC or CsA showed comparable efficacy to MPA/TAC in de novo kidney transplant patients. Non-inferiority of renal function, when pre-specified, was not shown, but the mean increase in eGFR from month 1 to 12 was comparable to MPA/TAC.

JC polyomavirus replication and associated disease in pediatric renal transplantation: an international CERTAIN Registry study

BACKGROUND

JC polyomavirus (JCPyV)-associated nephropathy (JCPyVAN) is a severe, but rare complication in adult renal transplant (RTx) recipients. Related data in pediatric patients are scarce.

METHODS

Based on the CERTAIN Registry, we therefore performed a multi-center, retrospective study on the JCPyV antibody status, prevalence of JCPyV replication, and its associated disease in 139 pediatric RTx recipients (mean age, 8.5 ± 5.3 years). JCPyV DNA in plasma and/or urine was measured by quantitative PCR at a median time of 3.2 (IQR, 0.3-8.1) years post-transplant.

RESULTS

53.2% of patients were JCPyV-seronegative prior to transplantation; younger age was associated with JCPyV seronegativity. 34/139 (24.5%) patients post-transplant showed active JCPyV replication in either urine (22.0%), plasma (13.4%), or both (7.6%). JCPyV viremia occurred significantly (p < 0.001) more often in patients with viruria (34.6%) than in those without (7.6%), but 7/118 (5.9%) had isolated viremia. High-level viruria (> 10⁷ copies/mL) was found in 29.6% of viruric patients. A higher net state of immunosuppression constituted an independent risk factor for JCPyV replication both in urine and plasma (OR 1.2, p < 0.02). Male patients tended to have a higher risk of JCPyV viremia than females (OR 4.3, p = 0.057). There was one male patient (0.7%) with JCPyVAN 7 years post-transplant, which resolved after reduction of immunosuppressive therapy. No patient exhibited progressive multifocal leukoencephalopathy.

CONCLUSIONS

This first multi-center study on JCPyV in pediatric renal transplant recipients shows that JCPyV replication is common (24.5%), with strong immunosuppression being a significant risk factor, but associated nephropathy is rare.

Prevalence and risk factors of human polyomavirus infections in non-malignant tonsils and gargles: the SPLIT study

The prevalence of 13 polyomaviruses (PyVs) in the tonsil brushings and gargles of immunocompetent children and adults was assessed. Patients undergoing tonsillectomy for benign indications were recruited in 19 centres in France. After resection, the entire outer surface of the right and left halves of the tonsils was brushed extensively. Gargles were also collected prior to surgery in selected adults. A species-specific multiplex assay was used to detect the DNA of 13 PyVs. In tonsil brushings (n=689), human PyV 6 (HPyV6) and Merkel cell PyV (MCPyV) were the most prevalent (≈15 %), followed by trichodysplasia spinulosa-associated PyV (TSPyV), BKPyV, Washington University PyV (WUPyV) and human PyV 9 (HPyV9) (1 to 5 %), and human PyV 7 (HPyV7), John Cunningham PyV (JCPyV) and Simian virus 40 (SV40) (<1 %), while no Karolinska Institute PyV (KIPyV), Malawi PyV (MWPyV), human PyV 12 (HPyV12) or Lyon IARC PyV (LIPyV) were detected. The prevalence of TSPyV and BKPyV was significantly higher in children versus adults, whereas for HPyV6 the opposite was found. HPyV6 and WUPyV were significantly more prevalent in men versus women. In gargles (n=139), MCPyV was the most prevalent (≈40 %), followed by HPyV6, HPyV9 and LIPyV (2 to 4 %), and then BKPyV (≈1 %), while other PyVs were not detected. MCPyV and LIPyV were significantly more prevalent in gargles compared to tonsil brushings, in contrast to HPyV6. We described differing patterns of individual PyV infections in tonsils and gargles in a large age-stratified population. Comparison of the spectrum of PyVs in paired tonsil samples and gargles adds to the current knowledge on PyV epidemiology, contributing towards a better understanding of PyV acquisition and transmission and its potential role in head and neck diseases.

Seroprevalence of fourteen human polyomaviruses determined in blood donors

The polyomavirus family currently includes thirteen human polyomavirus (HPyV) species. In immunocompromised and elderly persons HPyVs are known to cause disease, such as progressive multifocal leukoencephalopathy (JCPyV), haemorrhagic cystitis and nephropathy (BKPyV), Merkel cell carcinoma (MCPyV), and trichodysplasia spinulosa (TSPyV). Some recently discovered polyomaviruses are of still unknown prevalence and pathogenic potential. Because HPyVs infections persist and might be transferred by blood components to immunocompromised patients, we studied the seroprevalence of fourteen polyomaviruses in adult Dutch blood donors. For most polyomaviruses the observed seroprevalence was high (60–100%), sometimes slightly increasing or decreasing with age. Seroreactivity increased with age for JCPyV, HPyV6 and HPyV7 and decreased for BKPyV and TSPyV. The most recently identified polyomaviruses HPyV12, NJPyV and LIPyV showed low overall seroprevalence (~5%) and low seroreactivity, questioning their human tropism. Altogether, HPyV infections are common in Dutch blood donors, with an average of nine polyomaviruses per subject.

Particulate matter exposure increases JC polyomavirus replication in the human host

BACKGROUND

Human polyomaviruses (HPyVs) asymptomatically infect the human population during childhood and establish latency in the host. Viral reactivation and urinary excretion can occur when the immune system is impaired. Exposure to particulate air pollution, including the PM₁₀/PM_2.5 components, is a public health problem and has been linked to several disorders. Studies assessing the relationship between PM₁₀/PM_2.5 exposure and viral replication are lacking.

OBJECTIVES

To investigate the relationship between HPyVs viruria and PM₁₀/PM_2.5 exposures.

METHODS

Individual environmental exposure was assessed in 50 healthy adult volunteers using a chemical transport model (CTM) with a municipality resolution for daily PM₁₀ and monitoring stations data for daily PM_2.5 exposures. For each subject, a urine sample was collected, and HPyVs (JCPyV, BKPyV, MCPyV, HPyV6, HPyV7 and HPyV9) loads were determined. Zero-inflated negative binomial (ZINB) regression was used to model the count data, as it contained excessive zeros. Covariates were chosen by stepwise selection.

RESULTS

HPyVs DNA was detected in 54% (median:87.6*10⁵ copies/ml) of the urine samples. JCPyV was the prevalent (48%, (median viral load:126*10⁵ copies/ml). Considering the load of the most frequently measured HPyVs, JCPyV, in the count-part of the ZINB model, every unitary in PM measured 2 days before urine collection (PM Day -2) was associated with an increase in JCPyV load (PM₁₀: +4.0%, p-value = 0.002; PM_2.5: +3.6%, p-value = 0.005). In the zero-part, the significant predictor was the PM₁₀ measured 5 days before urine collection (+3%, p-value = 0.03).

CONCLUSIONS

The environmental levels of PM₁₀/PM_2.5 increase the JCPyV viruria. Our findings emphasize the need for studies assessing the influence of air pollution exposure on the risk of viral reactivation.

Elimination of BK viremia in renal transplant recipients by optimization of immunosuppressive medications without precipitating acute rejection

BK Polyomavirus-associated nephropathy (BKVAN) has been recognized as an increasing threat in renal transplant patients (RTP) for more than a decade. Reduction in immunosuppression is the mainstay of treatment through various options of treatment has been suggested. Published reports on these protocols have shown mixed results, and no randomized controlled trials have compared one strategy with another. In this context, we hypothesize that the appearance of BKV in the blood compels one to optimize the immunosuppression with possible long-term beneficial effects. We conducted a retrospective study among the RTP being followed up by the Renal Medicine Department at Royal Hospital who tested positive for BKV-polymerase chain reaction and whose immunosuppression was altered with a final aim to get rid of BK viremia, yet avoiding acute rejection. Results were analyzed by the clinical and statistical approach. Extensive literature review was carried out to look into the prevalence, prognosis, and treatment of BKVAN. In all the patients in whom BKV was detected alteration in immunosuppression resulted in eliminating the virus without precipitating acute rejection. The study shows that in the exercise of eliminating BKV by alteration of immunosuppression, we have "tailored" the immunosuppression in each particular RTPs, without precipitating acute rejection.

Antibody response to polyomavirus primary infection: high seroprevalence of Merkel cell polyomavirus and lymphoid tissue involvement

Human polyomaviruses (HPyVs) asymptomatically infect the human population establishing latency in the host, and their seroprevalence can reach 90% in healthy adults. Few studies have focused on the pediatric population, and there are no reports regarding the seroprevalence of all the newly isolated HPyVs among Italian children. Therefore, we investigated the frequency of serum antibodies against 12 PyVs in 182 immunocompetent children from Northeast Italy, by means of a multiplex antibody detection system. Additionally, secondary lymphoid tissues were collected to analyze the presence of HPyV DNA sequences using a specific real-time PCRs or PCRs. Almost 100% of subjects were seropositive for at least one PyV. Seropositivity ranged from 3% for antibodies against simian virus 40 (SV40) in children from 0 to 3 years, to 91% for antibodies against WU polyomavirus (WUPyV) and HPyV10 in children from 8 to 17 years. The mean number of PyV for which children were seropositive increased with the increasing of age: 4 standard deviations (SD) 1.8 in the 0-3-year group, 5 (SD 1.9) in the 4-7-year group, and 6 (SD 2.2) in the 8-17-year group. JC polyomavirus (JCPyV) DNA was detected in 1% of the adenoids, WUPyV in 12% of the tonsils, and 28% of the adenoids, and Merkel cell polyomavirus (MCPyV) was present in 6 and 2% of the tonsils and adenoids, respectively. Our study gives new insights on the serological evidence of exposure to PyVs during childhood, and on their possible respiratory route of transmission.

Anti-JC virus antibody sera positivity and index value among patients with multiple sclerosis may be correlated with age, sex, and area of residence

Anti-JC virus (JCV) antibody index is the predictive factor of progressive multifocal leukoencephalopathy (PML) for multiple sclerosis (MS) patients treating with natalizumab. The aim of this study is to evaluate the prevalence of anti-JCV antibody positivity and index among Iranian patients who are the candidate for natalizumab and its correlation with their demographic data and previous therapies. A cross-sectional design was assessed for receiving anti-JCV antibody test results between January 2014 and December 2016. Demographic data and disease characteristics were also obtained. Statistical analysis and logistic regression were done using SPSS. Among 803 MS patients that were observed, the prevalence of anti-JCV antibody positivity was 67.9% (mean of index = 2.23 ± 1.16) and 67.6% of positive patients had an index ≥ 1.5. Males were more antibody positive than females (81.7 and 64% respectively; significance (sig.) < 0.001, OR = 2.51, CI 1.65-3.81). The rate of positivity was lower in patients under the age of 18. Patients who lived in cold regions had significantly more prevalence of positivity (Num. = 403; sig. = 0.043 and OR = 1.86; CI 1.02-3.39) and with higher rate of index ≥ 1.5 (sig. = 0.017; OR = 3.99, CI 1.79-8.88). Disease onset age between 28 and 37 years were more positive compared to 18-27 years (N = 480; sig. = 0.02; OR = 1.85, CI 1.09-3.14). Age, male gender, onset age, and cold area of residency significantly influenced anti-JCV antibody sera positivity. Only age of onset and cold area of residency were related to the index. No significant difference was observed between type, dosage, and duration of previous immunosuppressant drugs and anti-JCV antibody positivity and index value.

Human polyomavirus in tonsillar microbiota of an Afghan population group

Some studies have evidenced the role of human polyomaviruses in head and neck squamous cell carcinoma. BK, JC and SV40 human polyoma viruses are widely recognized as etiological agents associated with malignancies. The aim of this study was to analyse the prevalence of BK, IC and SV40 in tonsillar microbiota in a group of Afghan volunteers. A sample of the tonsillar microbiota was taken from a single site using a sterile oral swab paper stick. A fixed volume of purified DNA from each sample was tested by quantitative real-time polymerase chain reactions to evaluate the number of human cells and the number of viral genomes in each sample. The cell number was evaluated via the quantification of a single copy genomic sequence, which is located in the HMBS locus. The median analyzed cell number in each reaction was 4343 (interquartile range 2074-8470). SV40 was never detected, while prevalence rate was 0.11 (C.I. 0.06-0.20) for BK and 0.10 (C.I. 0.05-0.19) for JC. Further studies are necessary to clarify whether polyomaviruses can be considered a risk factor of oral, oropharyngeal and laryngeal malignancies.

Human papilloma virus in the tonsillar microbiota of an Afghan population group

Cancer of the oral cavity is known to have a diverse aetiology that includes infectious agents. Human papilloma virus has been found to be associated with several types of human cancer, inclusive of cervical, vulvar, vaginal, penile, anal, and cancer of tonsil. The aim of this manuscript is to investigate the presence of human papilloma virus in tonsillar microbiota of an Afghan population group. A sample of the tonsillar microbiota was collected by oral swab paper stick from 80 healthy donors. The sample was investigated for the presence of high-risk human papillomavirus types 16, 18, 31 and 45 by real time PCR. Eight samples produced some positive endpoint signals for human papillomaviruses. The human papillomavirus 31 was the unique papillomavirus detected; its calculated prevalence rate was 0.10 (C.I. 0.05-0.19). However, the viral load was always very low, in the order of 10-3 viral genomes per cell. The high prevalence of high-risk human papillomavirus in healthy population suggest a need for further investigation on virus spreading and supports the development of vaccination strategies.

Urinary exosomal viral microRNA as a marker of BK virus nephropathy in kidney transplant recipients

Objective

Bkv-miR-B1-5p, one of the microRNAs encoded by BK virus, was recently reported to be elevated in the blood among the patients with BK virus nephropathy (BKVN). Urinary exosome was suggested to be a possible source of biomarker for kidney diseases, but it was unknown whether it could contain viral microRNA as well as human microRNAs. The aim of this study was to evaluate whether urinary exosomal BK viral microRNA were expressed during replication and could be used to diagnose BKVN in kidney transplant recipients.

Materials and methods

In a cross-sectional multicenter study, we collected and analyzed 458 graft biopsies from 385 kidney transplant recipients. Urine samples were collected at the time of graft biopsy, and microRNAs in urinary exosome were measured once. For 13 patients with BKVN and 67 age, sex-matched kidney transplant recipients, we measured BK viral microRNA B1-5p, 3p and human microRNA-16 in urinary exosomal fraction and compared the diagnostic value with BK viral load in plasma and urine.

Results

Pathology proven BKVN was diagnosed in 13 patients (2.8%). High levels of bkv-miR-B1-5p and bkv-miR-B1-3p were shown in all patients with BKVN. Meanwhile, plasma BK viral load assay (cut-off value of ≥ 4.0 log₁₀ copies/mL) showed false negative in 3 cases and urinary BK viral load assay (cut-off value of ≥ 7.0 log₁₀ copies/mL) showed false negative in 1 case among these 13 patients. The receiver operator characteristics curve analysis for bkv-miR-B1-5p and bkv-miR-B1-5p/miR-16 showed excellent discriminative power for the diagnosis of BKVN, with area under the curve values of 0.989 and 0.985, respectively.

Conclusions

This study suggests that urinary exosomal bkv-miR-B1-5p and bkv-miR-B1-5p/miR-16 could be surrogate markers for the diagnosis of BKVN.

CMV and BKPyV Infections in Renal Transplant Recipients Receiving an mTOR Inhibitor-Based Regimen Versus a CNI-Based Regimen: A Systematic Review and Meta-Analysis of Randomized, Controlled Trials

BACKGROUND AND OBJECTIVES

The objective of this meta-analysis is to compare the incidences of cytomegalovirus and BK polyoma virus infections in renal transplant recipients receiving a mammalian target of rapamycin inhibitor (mTOR)-based regimen compared with a calcineurin inhibitor-based regimen.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a comprehensive search for randomized, controlled trials up to January of 2016 addressing our objective. Other outcomes included acute rejection, graft loss, serious adverse events, proteinuria, wound-healing complications, and eGFR. Two review authors selected eligible studies, abstracted data, and assessed risk of bias. We assessed quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation methodology.

RESULTS

We included 28 randomized, controlled trials with 6211 participants classified into comparison 1: mTOR inhibitor versus calcineurin inhibitor and comparison 2: mTOR inhibitor plus reduced dose of calcineurin inhibitor versus regular dose of calcineurin inhibitor. Results showed decreased incidence of cytomegalovirus infection in mTOR inhibitor-based group in both comparison 1 (risk ratio, 0.54; 95% confidence interval, 0.41 to 0.72), with high quality of evidence, and comparison 2 (risk ratio, 0.43; 95% confidence interval, 0.24 to 0.80), with moderate quality of evidence. The available evidence neither confirmed nor ruled out a reduction of BK polyoma virus infection in mTOR inhibitor-based group in both comparisons. Secondary outcomes revealed more serious adverse events and acute rejections in mTOR inhibitor-based group in comparison 1 and no difference in comparison 2. There was no difference in graft loss in both comparisons. eGFR was higher in the mTOR inhibitor-based group in comparison 1 (mean difference =4.07 ml/min per 1.73 m2; 95% confidence interval, 1.34 to 6.80) and similar to the calcineurin inhibitor-based group in comparison 2. More proteinuria and wound-healing complications occurred in the mTOR inhibitor-based groups.

CONCLUSIONS

We found moderate- to high-quality evidence of reduced risk of cytomegalovirus infection in renal transplant recipients in the mTOR inhibitor-based compared with the calcineurin inhibitor-based regimen. Our review also suggested that a combination of a mTOR inhibitor and a reduced dose of calcineurin inhibitor may be associated with similar eGFR and rates of acute rejections and serious adverse events compared with a standard calcineurin inhibitor-based regimen at the expense of higher incidence of proteinuria and wound-healing complications.

[A molecular epidemiological study of KI polyomavirus and WU polyomavirus in children with acute respiratory infection in Tianjin, China]

OBJECTIVE

To investigate the relationship of KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) with acute respiratory infection in children in Tianjin, China.

METHODS

A total of 3 730 nasopharyngeal secretions were collected from hospitalized children with acute respiratory infection in Tianjin Children's Hospital from January 2011 to December 2013. Viral nucleic acid was extracted, and virus infection (KIPyV and WUPyV) was determined by PCR. Some KIPyV-positive and WUPyV-positive PCR products were subjected to sequencing. Sequencing results were aligned with the known gene sequences of KIPyV and WUPyV to construct a phylogenetic tree. Amplified VP1 fragments of KIPyV were inserted into the cloning vector (PUCm-T) transformed into E. coli competent cells. Positive clones were identified by PCR and sequencing. The nucleotide sequences were submitted to GenBank. In addition, another seven common respiratory viruses in all samples were detected by direct immunofluorescence assay.

RESULTS

In the 3 730 specimens, the KIPyV-positive rate was 12.14% (453/3 730) and the WUPyV-positive rate was 1.69% (63/3 730). The mean infection rate of KIPyV was significantly higher in June and July, while the mean infection rate of WUPyV peaked in February and March. Most of the KIPyV-positive or WUPyV-positive children were <3 years. The co-infections with KIPyV, WUPyV, and other respiratory viruses were observed in the children. The co-infection rate was 2.31% (86/3 730) and there were nine cases of co-infections with WUPyV and KIPyV. Thirty-five KIPyV-positive and twelve WUPyV-positive PCR products were sequenced and the alignment analysis showed that they had high homology with the known sequences (94%-100% vs 95%-100%). The VP1 gene sequences obtained from two KIPyV strains in this study were recorded in GenBank with the accession numbers of KY465925 and KY465926.

CONCLUSIONS

For some children with acute respiratory infection in Tianjin, China, the acute respiratory infection may be associated with KIPyV and WUPyV infections. KIPyV infection is common in summer, and WUPyV infection in spring. The epidemic strains in Tianjin have a high homology with those in other regions.

Multiplex detection in tonsillar tissue of all known human polyomaviruses

BACKGROUND

In the past few years, eleven new human viruses have joined the two previously known members JCPyV and BKPyV of the Polyomaviridae family, by virtue of molecular methods. Serology data suggest that infections with human polyomaviruses (HPyVs) occur since childhood and the viruses are widespread in the general population. However, the viral persistence sites and transmission routes are by and large unknown. Our previous studies demonstrated that the four new HPyVs - KIPyV, WUPyV, MCPyV and TSPyV - were present in the tonsils, and suggested lymphoid tissue as a persistent site of these emerging human viruses. We developed a Luminex-based multiplex assay for simultaneous detection of all 13 HPyVs known, and explored their occurrence in tonsillar tissues of children and adults mostly with tonsillitis or tonsillar hypertrophy.

METHODS

We set up and validated a new Luminex-based multiplex assay by using primer pairs and probes targeting the respective HPyV viral protein 1 (VP1) genes. With this assay we tested 78 tonsillar tissues for DNAs of 13 HPyVs.

RESULTS

The multiplex assay allowed for simultaneous detection of 13 HPyVs with high analytical sensitivity and specificity, with detection limits of 100-102 copies per microliter, and identified correctly all 13 target sequences with no cross reactions. HPyV DNA altogether was found in 14 (17.9%) of 78 tonsils. The most prevalent HPyVs were HPyV6 (7.7%), TSPyV (3.8%) and WUPyV (3.8%). Mixed infection of two HPyVs occurred in one sample.

CONCLUSIONS

The Luminex-based HPyV multiplex assay appears highly suitable for clinical diagnostic purposes and large-scale epidemiological studies. Additional evidence was acquired that the lymphoid system plays a role in HPyV infection and persistence. Thereby, shedding from this site during reactivation might take part in transmission of the newly found HPyVs.

Specific and quantitative detection of Human polyomaviruses BKPyV and JCPyV in the healthy Pakistani population

BACKGROUND

The BK Polyomavirus (BKPyV) and JC polyomavirus (JCPyV) infections are widespread in human population and have been associated with severe kidney and brain disorders, respectively. The viruses remain latent primarily in reno-urinary tract, reactivating only in case of a compromised immune system. The seroepidemiology and molecular prevalence of BKPyV and JCPyV have been widely studied both in healthy and immunocompromised patients worldwide. However, data regarding the prevalence of these viruses in the immunocompetent or apparently healthy Pakistani population is lacking. Herein, we present the first ever report on quantitative prevalence of BKPyV and JCPyV in the peripheral blood of a randomly selected cohort of healthy Pakistani population.

METHODS

A total of 266 whole blood samples were examined. The subjects were divided into three age groups: ≤ 25 years (young), 26-50 years (middle) and ≥ 51 years (elder). Absolute real time PCR assay was designed to quantify the BKPyV and JCPyV viral copy numbers in the range of 106 to 100 copies/mL.

RESULTS

Overall, BKPyV was detected in 27.1% (72/266) individuals while JCPyV in 11.6% (31/266) indicating significant difference (p < 0.005) in the distribution of these two viruses. The prevalence of BKPyV significantly decreased from 51% (49/96) in young age group to 8.2% (7/85) in eldest age group. Whereas, JCPyV positivity rate slightly increased from 8.3% (8/96) in young age group to 11.8% (10/85) in elder age group. The median viral load was calculated as 6.2 log and 3.38 log copies/mL of blood for BKPyV and JCPyV, respectively. Notably, no significant difference in viral load of either of the subtypes was found between different age groups.

CONCLUSION

The current study provides an important baseline data on the prevalence and viral load of circulating BKPyV and JCPyV in Pakistani population. The prevalence and viral load of BKPyV was comparatively higher than JCPyV. The prevalence of BKPyV significantly decreased with increase in age while JCPyV positivity rate slightly increased with increasing age. Viral load of both BKPyV and JCPyV was not correlated with the individual ages.

Detection of a new JCV strain of genotype A in a subpopulation of colorectal adenocarcinomas in Tunisia

The etiology of colorectal cancer (CRC) remains elusive in spite of major advances in knowledge of this disease and related risk factors. Several studies report the detection of human polyomavirus JC (JCV) in colorectal tumors and some suggest its association with CRC. Since many known human virus associations with cancer are linked to factors such as ethnic and geographical origin, it is interesting to search for the postulated association of JCV with CRC in different populations and regions. In this perspective, the present work was undertaken to assess the presence of JCV in CRC tumors in Tunisia. Fresh biopsies were obtained from both colorectal tumors and adjacent normal tissues of 47 CRC patients. Only tumors diagnosed as adenocarcinomas were included in the present study. Twenty patients with other gastroenterological disorders were taken as controls. DNA was extracted from fresh biopsies or formalin-fixed, paraffin-embedded tissue sections. A region of the viral T-Ag gene was amplified by PCR and the DNA amplicons were subjected to automated sequencing. JCV DNA was found in 22 (46%) of the adenocarcinomas but in none of the normal mucosa biopsies of either CRC or control patients. Sequence analysis indicated that the amplified DNA belonged to a new JCV variant of genotype A. The presence of JCV DNA was correlated with tumor location and grade. The data obtained suggest that JCV may be associated either with a subpopulation of colorectal tumors or with CRC in general, possibly through a hit and run mechanism.

Human Washington University Polyomavirus in Patients with Respiratory Tract Infection in Kuwait

OBJECTIVE

To determine Washington University (WU) polyomavirus strains circulating among hospitalized patients with respiratory tract infections (RTI) in Kuwait.

MATERIALS AND METHODS

Samples from 459 hospitalized children and adult RTI patients were screened for respiratory viruses by polymerase chain reaction from April 2013 to April 2016. The VP2 gene from WU virus (WUV)-positive samples was sequenced and subjected to phylogenetic analysis.

RESULTS

Of the 459 hospitalized RTI patients, 18 (3.9%) patients were positive for WUV infection. WUV infection was common among children aged ≤11 years (9 patients, 50%). Among the 18 WUV-infected hospitalized patients, viral co-infection was detected in 9 patients (50%). The most common viruses associated with mixed infection were respiratory syncytial virus and human rhinovirus (2 patients, 11.1% each). Of the 18 WUV-infected patients, 4 were sequenced and subjected to phylogenetic analysis. The circulating strains belong to type Ia and IIIb.

CONCLUSION

This study enabled us to detect WUV among hospitalized RTI patients. Co-infection with other respiratory viruses was notable. Two circulating WUV genotypes (Ia and IIIb) were identified among hospitalized RTI patients in Kuwait.

Serum biomarkers of polyomavirus infection and risk of lung cancer in never smokers

BACKGROUND

Lung cancer in never smokers is a significant contributor of cancer mortality worldwide. In this analysis, we explored the role of nine human polyomaviruses, including JC virus (JCV), BK virus (BKV) and Merkel cell virus (MCV), in lung cancer development in never smokers as there are data to support that polyomaviruses are potentially carcinogenic in the human lung.

METHODS

We used multiplex serology to detect serum antibodies to polyomaviruses in a nested case-control design combining lung cancer cases and controls from four cohort studies - NYU Women's Health Study (NYU-WHS), Janus Serum Bank, Shanghai Women's Health Study and Singapore Chinese Health Study (SCHS).

RESULTS

The final analyses included 511 cases and 508 controls. Seroprevalence for each polyomavirus showed significant heterogeneity by study, but overall there were no statistically significant differences between cases and controls. In total, 69.1% of the cases and 68.7% of the controls were seropositive for JCV VP1 antibody. Seropositivity for BKV was higher at 89.0% in cases and 89.8% in controls and lower for MCV at 59.3% in cases and 61.6% in controls. Similar results were obtained after adding an additional retrospective case-control study (Xuanwei study) to the analysis.

CONCLUSIONS

Our results do not support the hypothesis that seropositivity for polyomaviruses is associated with increased lung cancer risk in never smokers. Future research to evaluate relationship between polyomavirus infection and lung carcinogenesis should focus more on evaluating the presence of virus or viral nucleic acids (DNA or RNA) in lung tumour samples.

Polyomavirus Nephropathy in Kidney Transplantation

Polyomavirus nephropathy has become an important complication in kidney transplantation, with a prevalence of 1% to 8%. Unfortunately, the risk factors for polyomavirus nephropathy and renal allograft loss are not well defined. The definitive diagnosis is made through assessment of a kidney transplant biopsy. Recently, noninvasive urine and serum markers have been used to assist in polyomavirus nephropathy diagnosis and monitoring. Primary treatment is immunosuppression reduction, but must be balanced with the risks of rejection. No antiviral treatments for polyomavirus nephropathy have been approved by the Food and Drug Administration. Although cidofovir has shown in vitro activity against murine polyomaviruses, and has been effective in some patients, it is associated with significant nephrotoxicity. Graft loss due to polyomavirus nephropathy should not be a contraindication to retransplantation; however, experience is limited. This review presents potential risk factors, screening, diagnostic and monitoring methods, therapeutic management, and retransplantation experience for polyomavirus nephropathy.

The Prevalence and Prognostic Significance of Polyomavirus Infection in Patients with Urothelial Carcinoma of the Bladder

PURPOSE

Human polyomaviruses (PV) has been associated with oncogenicity; however, the association between human bladder cancer and PV remains inconclusive. Moreover, whether PV has the interaction with p53 in tumorigenesis and their prognostic significance on human bladder cancer has yet to be determined.

MATERIALS AND METHODS

Bladder tumor specimens and clinical parameters from 74 patients with urothelial carcinoma were collected. Immunohistochemical analysis using monoclonal antibodies specific to PV large tumor antigen (TAg) and p53 protein was performed to investigate the involvement of PV in human bladder tumorigenesis and the prognostic significance of TAg and p53 expressions using Cox proportional hazards model.

RESULTS

The mean age of the 74 patients at diagnosis was 64 years and 61 (82.4%) were male. The expression of PV TAg protein was found in 45 (60.8%) tumor samples, but was not correlated with the expression of p53 (P = .280). The detection of PV TAg was significantly associated with tumor stage (P = .001) but not decreased overall survival (OS) or cancer-specific survival (CSS) (P = .661 and .738, respectively). However, the p53 overexpression was significantly associated with decreased CSS (P = .028). In multivariate Cox proportional hazards analysis, age and p53 overexpression were predictors of OS (P = .026) independently of tumor stage and CSS (P = .042), respectively.

CONCLUSION

We found that PV, which was detected in a significant percentage of tumor specimens, may be an important co-factor in the tumorigenesis of the bladder in humans. However, only p53 overexpression was associated with predicting CSS independently of tumor stage.&nbsp.

The Natural History of Human Polyomaviruses and Herpesviruses in Early Life--The Rhea Birth Cohort in Greece

Sparse data exist on the patterns and determinants of acquisition of polyomaviruses and herpesviruses in childhood. We measured immunoglobulin G seroreactivity against 10 polyomaviruses (BKPyV, JCPyV, KIPyV, WUPyV, MCPyV, HPyV6, HPyV7, TSPyV, HPyV9, HPyV10) and 5 herpesviruses (Epstein Barr virus (EBV), cytomegalovirus (CMV), herpes simplex virus types 1 and 2, human herpesvirus 8) using multiplex serology on blood samples collected at birth (cord blood, n = 626) and at follow-up at 3 years (n = 81) and 4 years (n = 690) of age among the Rhea birth cohort recruited in Greece from pregnant women in 2007-2008. We used Poisson regression with robust variance to identify determinants of seropositivity at age 4. Seroprevalence of polyomaviruses ranged from 38.5% to 99.8% in cord blood and from 20.9% to 82.3% at age 4. Seroprevalence of EBV, CMV, herpes simplex virus types 1 and 2, and human herpesvirus 8 was 99.4%, 74.9%, 26.2%, 8.0%, and 1.6% in cord blood and 52.5%, 25.8%, 3.6%, 1.4%, and 0% at age 4, respectively. Determinants of seropositivity at age 4 were cord seropositivity (JCPyV, HPyV7, HPyV10, CMV), vaginal delivery (HPyV10), breastfeeding (CMV), younger age at day-care entry (BKPyV, KIPyV, WUPyV, TSPyV, HPyV10, HPyV9, EBV, CMV), and swimming pool attendance (BKPyV, KIPyV, WUPyV, HPyV10). Television viewing, parental stress, and hygiene practices were inversely associated with the seroprevalence of polyomaviruses and herpesviruses.

Polyomavirus infections and its clinical relevance in cancer patients: A Prospective Study

BK and JC polyomaviruses (PyV) have been demonstrated to be associated with the pathogenesis of various human cancers. We aimed to investigate the impact of BK and JC polyomavirus infections on several clinical parameters in different human cancers. A total of 150 cancer patients were included in the study (51 patients with solid tumors, 48 patients with lymphomas and 51 patients with leukemias). Amplification of PyV DNA was performed using a semi-nested version of Polymerase chain reaction targeting the T genomic region of PyV. The polyomavirus load was determined using real-time PCR assay. The clinical data were collected. Polyomavirus DNA could be detected in 84 (56%) of 150 of all cancerous patients. The solid tumors had the lowest proportion of JCV (6 (11.8%) of 51), whereas had the highest proportion of JCV (200copies/μl). JCV was more frequent among NHL patients (30%) and absent in HL patients (0%). During follow-up, PyV positivity decreased significantly (p=0.004) in lymphoma patients (n=28). Although PyV positivity decreased significantly from 39% to 7% in 28 of 48 lymphoma patients after treatment, it significantly persisted in leukemic patients after treatment (from 22% to 38%). JC was more frequent among leukemic patients with leukopenia. The presence of JC polyomavirus was more frequent among leukemic patients without any significant impact on their overall survival.

Different behaviour of BK-virus infection in liver transplant recipients

Polyomavirus BK (BKV) infects up to 90% of the general population. After primary infection, occurring early during childhood, a state of non-replicative infection is established in the reno-urinary tract, without complications for immunocompetent hosts. In immunocompromised individuals, particularly transplanted patients, asymptomatic BKV viremia and/or viruria can be observed. Renal grafts may also be sources of infection as BKV prefers kidneys rather than other solid organs for transplantation such as the liver. The mechanism behind the higher incidence of BKV infection in kidney transplant patients, compared to liver or heart transplantation, is unclear and the prevalence of BKV infection in non-renal solid organ transplants has not been yet thoroughly investigated. We evaluated the prevalence of Polyomavirus BK infection among liver transplant recipients. A PubMed search was conducted using the terms BKV infection AND liver transplant recipients; BKV AND non-renal solid organ transplant*; BKV infection AND immunosuppression; the search was limited to title/abstract and English-language articles published from 2000, to March 2015. Eleven relevant studies suggest that the prevalence of BKV viruria and/or viremia among liver transplant recipients is less than that reported in kidney or heart transplant recipients, except when chronic kidney disease (CKD) is present at the same time. Data also suggest that viruric and viremic patients have higher levels of serum creatinine than BKV negative patients. Moreover, no specific immunosuppressive drugs are associated with the onset of BKV nephropathy. The comorbidity of transplantation and CKD could play a major role in promoting BKV replication.

Acquisition of human polyomaviruses in the first 18 months of life

We investigated the presence of 4 human polyomaviruses (PyVs) (WU, KI, Merkel cell, and Malawi) in respiratory specimens from a community-based birth cohort. These viruses typically were acquired when children were ≈1 year of age. We provide evidence that WU, KI, and Malawi, but not Merkel cell PyVs, might have a role in respiratory infections.

Polyomavirus Hominis 1(BK virus) Infection in Prostatic Tissues: Cancer versus Hyperplasia

PURPOSE

Polyomavirus hominis 1, better known as BK virus (BKV) infection might be a predisposing factor for prostate cancer (PCa). The aim of this study was to compare the frequency of BK virus infection in pathological specimens of patients with PCa compared to patients with benign prostatic hyperplasia.

MATERIALS AND METHODS

From July 2011 to June 2012, paraffin-embedded tissue blocks of patients with PCa (60 specimens) and also with benign prostatic hyperplasia (60 specimens) were investigated. After DNA purification, existence of virus nucleic acid was assessed by polymerase chain reaction.

RESULTS

Viral DNA was identified in 9 patients (15%) with benign prostatic hyperplasia (BPH) and 17 patients (28%) with PCa (P = .076). In patients with PCa, viral DNA was observed more often in those with lower total Gleason scores (P = .045).

CONCLUSION

The frequency of BK virus infection in PCa patients was higher than BPH patients. BK virus was more often observed in patients with lower Gleason scores. Less detection of BK virus DNA in overt cancer may prove the activity of the virus which paves the way for tumorigenic transformation at early stages of PCa.

Common exposure to STL polyomavirus during childhood

STL polyomavirus (STLPyV) was recently identified in human specimens. To determine seropositivity for STLPyV, we developed an ELISA and screened patient samples from 2 US cities (Denver, Colorado [500]; St. Louis, Missouri [419]). Overall seropositivity was 68%–70%. The age-stratified data suggest that STLPyV infection is widespread and commonly acquired during childhood.

Frequency and subtype of BK virus infection in Iranian patients infected with HIV

Human polyomavirus BK virus (BKV) is a double-stranded DNA virus that infects approximately 90 % of the general population as a subclinical or mild infection. In immunosuppressed patients, such as HIV cases, BKV may be reactivated resulting hemorrhagic cystitis and tubulointerstitial nephritis. However, there are limited studies on prevalence and molecular epidemiology of BKV in Iran. We therefore aimed to evaluate the prevalence and subtypes of BKV in Iranian HIV patients. A total of 99 patients with HIV infection were enrolled in the study. Presence of BKV DNA in plasma was evaluated by nested PCR. PCR products were sequenced directly, and phylogenetic analysis was performed. BKV DNA was detected in 8.08 % of HIV patients. BKV viremia presented in 4 out of 25 patients (16 %) not receiving antiretroviral therapy in comparison with 4 out 74 of HAART-treated patients (5.4 %) (P = 0.023). In patients with CD4 counts ≥200 cells/mm(3), viremia was found more commonly (7/80 = 8.8 %) than in those with lower counts (1/19 = 5.2 %) (not significant). All sequenced BKV isolates belonged to subtype Ib-2. Our findings indicated that the prevalence of BKV viremia is relatively prevalent in patients with HIV infection and significantly higher in naïve than HAART-treated cases. Therefore, HAART can eliminate BKV infection from plasma and reduce viremia although the actual implication of BKV viremia in HIV patients is not clear.

Management of BK virus nephropathy in kidney transplant recipients at the Royal Hospital - Clinical Audit - Oman

OBJECTIVES

Nephropathy from BK virus (BKV) infection is a growing challenge in kidney transplant recipients globally. It is the result of contemporary potent immunosuppressives aimed at reducing acute rejection and improving allograft survival. Untreated BK virus infections lead to kidney allograft dysfunction or loss. Decreased immunosuppression is the principle treatment but predisposes to acute and chronic rejection. Screening for early detection and prevention of symptomatic BK virus nephropathy may improve outcomes. Although no approved antiviral drug is available, leflunomide, cidofovir, quinolones, and intravenous immunoglobulin have been used. Since the introduction of the new immunosuppressive agents in the transplant regimen at the Royal Hospital, Few cases of BK virus have been detected, and the challenge was to decide upon the best treatment option.

MATERIALS AND METHODS

The audit was carried out at the Royal Hospital-Oman between January 2010 and December 2012. The nephrology consultant and the clinical pharmacist reviewed all the BK cases and the Royal Hospital. Extensive literature review carried out by the pharmacist to look into the prevalence, prognosis and treatment of BK nephropathy. A treatment protocol was prepared by the clinical pharmacist through guidance of the consultant and was peer reviewed by team of clinical pharmacists and nephrology doctors and approved by the consultant.

RESULTS

The audit included 19 patients with positive BK virus ployoma nephropathy. The treatment options were applied stepwise in all the patients with BK virus nephropathy with success rate more than 70%.

CONCLUSIONS

BK virus nephropathy is emerging at an alarming rate and requires increasing awareness. The uses of current treatment options are still questionable. Our audit confirms that reducing immunosuppression appears to be the criterian standard for the treatment of BK nephropathy.

Malawi polyomavirus is a prevalent human virus that interacts with known tumor suppressors

Malawi polyomavirus (MWPyV) is a recently identified human polyomavirus. Serology for MWPyV VP1 indicates that infection frequently occurs in childhood and reaches a prevalence of 75% in adults. The MWPyV small T antigen (ST) binds protein phosphatase 2A (PP2A), and the large T antigen (LT) binds pRb, p107, p130, and p53. However, the MWPyV LT was less stable than the simian virus 40 (SV40) LT and was unable to promote the growth of normal cells. This report confirms that MWPyV is a widespread human virus expressing T antigens with low transforming potential.