Analysis of risk factors of high-level BK viruria after renal transplantation / 器官移植

Objective To analyze the risk factors of high-level BK viruria after renal transplantation and the significance in preventing BK virus-associated nephropathy (BKVAN). Methods Clinical data of 262 renal transplant recipients with regular follow-up data were retrospectively analyzed. According to the DNA load of BK virus, all recipients were divided into the high-level BK viruria group (n=35) and non-high-level BK viruria group (n=227). The incidence of high-level BK viruria after renal transplantation was summarized. The risk factors of high-level BK viruria after renal transplantation were analyzed by univariate analysis and multivariate analysis. Survival curve was delineated by Kaplan-Meier method, and survival analysis of recipients was performed. Results Among 262 renal transplant recipients, 35 cases developed high-level BK viruria with an incidence of 13.4%. The median time of occurrence of high-level BK viruria was 181 (126, 315) d. The incidence was the highest within 6 months after renal transplantation, gradually decreased from 6 months to 2 years, and then increased after 2 years. Univariate analysis showed that the history of antithymocyte globulin (ATG) treatment, acute rejection (AR), donation type and delayed graft function (DGF) were the risk factors of high-level BK viruria after renal transplantation (all P < 0.05). Multivariate Cox regression analysis demonstrated that donation after brain death followed by cardiac death (DBCD), AR and DGF were the independent risk factors of high-level BK viruria after renal transplantation. The 1-, 3- and 5-year survival rates of recipients with ATG treatment history, AR, DGF and donation type of DBCD were significantly lower than those with non-ATG treatment history, non-AR, non-DGF and other donation types [donation after brain death (DBD), donation after cardiac death (DCD) and living organ donation] respectively (all P < 0.05). Conclusions DBCD, AR and DGF are the independent risk factors of high-level BK viruria after renal transplantation. Strengthening the postoperative monitoring of these recipients and delivering early intervention may effectively prevent BKVAN.

Analysis of 11 cases of ABO incompatible living kidney transplantation / 器官移植

Objective To evaluate the clinical efficacy and safety of ABO incompatible living kidney transplantation(ABOi-KT). Methods Clinical data of 11 donors and recipients with ABOi-KT were retrospectively analyzed. All the recipients were treated with desensitization before operation. The recovery condition of renal function and blood type antibody titer of the ABOi-KT recipients were monitored after operation. The incidence of complications and clinical prognosis of ABOi-KT recipients were observed. Results The serum creatinine (Scr) of 11 recipients were well recovered after ABOi-KT. No delay in recovery of graft renal function. Among them, 2 recipients experienced a significant increase in the Scr level at postoperative 14 and 45 d respectively, 1 recipient showed criticality cellular rejection after operation and 1 recipient presented with elevated Scr level at postoperative 33 d, accompanied by an increase in blood type antibody titer. The condition became stable after corresponding treatment. The remaining 7 recipients obtained normal graft renal function and postoperative blood type antibody titer did not rebound. During postoperative follow-up until November 2018, no recipient died or graft renal failure occurred. The survival rate of the recipient and graft renal was 100%. Among them, 3 patients suffered from postoperative complications, including pulmonary infection, BK viruria and granulocytopenia, which were cured after symptomatic treatment. Conclusions ABOi-KT is safe, feasible and yields high long-term clinical efficacy, which can increase the source of living donor kidney and relieve the shortage of donor kidney.

Relationship between metabolic rate of tacrolimus and BK virus infection early after renal transplantation / 器官移植

Objective To investigate the relationship between the metabolic rate of tacrolimus (FK506) and BK virus infection early after renal transplantation. Methods Eighty recipients undergoing allogenic renal transplantation in Institute of Organ Transplantation of the 309thHospital of Chinese People's Liberation Army were recruited in this study. The polymorphism of cytochrome P450 (CYP) 3A5 gene was detected in 80 recipients. All patients were divided into fast metabolism group ( CYP3A5*1/*3 and CYP3A5*1/*1 genotypes, n=38) and slow metabolism group ( CYP3A5*3/*3 genotype, n=42) based on the gene detection results. The distribution of CYP3A5 genotypes in 80 recipients was analyzed. The metabolic rate [concentration/dose ratio (C/D value)] of FK506 was statistically compared between two groups. The incidence of BK virus infection events [BK viruria, BK viremia and BK virus nephropathy(BKVN)] within postoperative 6 months were compared between two groups. Results Among 80 recipients, 5 cases (6%) were detected with CYP3A5*1/*1 genotype, 33 (41%) with CYP3A5*1/*3 genotype, and 42 (53%) with CYP3A5*3/*3 genotype. Among the 160 alleles in 80 recipients, 117 CYP3A5*3 allele were identified, suggesting that the mutation rate of CYP3A5*3 allele was 73.1%. In the fast metabolism group, the C/D values at postoperative 1, 3, and 6 months were significantly lower than those in the slow metabolism group (all P<0.01). The incidence rates of BK viruria in the fast and slow metabolism groups were 37% and 29%, 18% and 2% for BK viremia, and 3% and 0 for BKVN, respectively. In the fast metabolism group, the incidence of BK virenia was significantly higher than that in the slow metabolism group (P=0.02). The incidence of BK viruria and BKVN did not significantly differ between two groups (both P>0.05). Conclusions According to the CYP3A5 genotyping outcomes, the recipients with a high metabolic rate of FK506 have a high risk of BK viremia early after renal transplantation.

Clinical study on the effect of BK virus infection on renal allograft function after renal transplantation / 器官移植

Objective To analyze the impairment of renal allograft function in renal transplant recipients caused by BK virus infection after renal transplantation. Methods Clinical data of 210 recipients who underwent allogenic renal transplantation and received BK virus monitoring regularly were analyzed retrospectively. The incidence of BK viruria, viremia and BK virus nephropathy (BKVN) after renal transplantation was summarized. The effect of BK virus infection on renal allograft function and prognosis of renal allograft function after the removement of BK virus were analyzed. Results Among the 210 recipients, there were 46 cases with pure viruria, 46 cases with viremia complicated with viruria and 7 cases with BKVN confirmed by pathological biopsy. The level of serum creatinine (Scr) in the recipients with viremia after renal transplantation was linearly related to BK viral load in urine and blood (r=0.594, 0.672, both P<0.01). The level of Scr increased significantly when BK viral load in blood of the recipients with viremia was found positive for the first time, and increased continuously after viremia sustained. And the level of Scr decreased slightly when blood viral load turned to negative after treatment, but still significantly higher than before virus infection. All the above differences were statistically significant (all P<0.05). Compared with the basic level, there was no significant difference in the level of Scr of recipients with pure viruria during positive viruria (all P>0.05). Conclusions It will impair the renal allograft function when BK viremia occurs after renal transplantation, and it is necessary to monitor viral infection regularly. Once the blood BK virus is found positive, it shall be implemented immediately to reduce the intensity of immunosuppression as the preferred clinical intervention.

High-level viruria as a screening tool for BK virus nephropathy in renal transplant recipients

BACKGROUND: Although early monitoring of BK virus infection in renal transplant patients has led to improved outcomes over the past decade, it remains unclear whether monitoring for viremia is the best screening tool for BK virus nephropathy (BKVN). METHODS: We conducted a retrospective review of the medical records of 368 renal transplant recipients who had a minimum of 18 months of posttransplantation follow-up. The relationship between the presence of BK viruria and a composite end point of BK viremia/BKVN was established, and the predictive value of high-grade BK viruria for development of viremia/BKVN was determined. RESULTS: High grade of BK viruria was present in 110 (30.1%) of the renal transplant recipients. BK viremia/BKVN was present in 64 (17.4%) patients and was 50 times more likely to be present in patients with high-grade BK viruria. The risk of developing BK viremia/BKVN was 3 times higher in high-grade viruria patients, and viruria preceded viremia by nearly 7 weeks. CONCLUSION: The presence of high-grade viruria is an early marker for developing BK viremia/BKVN. Detection of high-grade viruria should prompt early allograft biopsy and/or preemptive reduction in immunosuppression.

Molecular detection and phylogenetic relationship of wild-type strains of canine distemper virus in symptomatic dogs from Uberlândia, Minas Gerais / Detecção molecular e relação filogenética de cepas selvagens do vírus da cinomose canina em cães sintomáticos oriundos de Uberlândia, Minas Gerais

This study investigated the occurrence of canine distemper virus (CDV) by evaluating the presence of viral RNA within urine samples of dogs from Uberlândia, MG, with clinical manifestations suggestive of infection by CDV by targeting the CDV N gene. Of the clinical samples collected ( n =33), CDV viruria was detected in 45.5%. Five dogs died spontaneously; all had characteristic CDV-associated histopathological alterations and demonstrated CDV viruria. Statistical analyses revealed that the age, gender, breed, or the organ system of the dog affected had no influence on the occurrence of canine distemper. Myoclonus and motor incoordination were the most significant neurological manifestations observed. A direct association was observed between keratoconjunctivitis and dogs with CDV viruria. These findings suggest that CDV viruria in symptomatic dogs might not be age related, and that symptomatic dogs can demonstrate clinical manifestations attributed to CDV without viruria identified by RT-PCR. Additionally, the results of the sequence identities analysed have suggested that all Brazilian wild-type strains of CDV currently identified are closely related and probably originated from the same lineage of CDV. Nevertheless, phylogenetic analyses suggest that there are different clusters of wild-type strains of CDV circulating within urban canine populations in Brazil.

A presença do ácido nucleico (RNA) do vírus da cinomose canina (CDV) foi avaliada por meio da amplificação parcial do gene N pela técnica RT-PCR realizada em urina de cães provenientes de Uberlândia, Minas Gerais, que apresentavam sinais clínicos sugestivos de cinomose. Das 33 amostras de urina avaliadas, o CDV foi identificado em 45,5%. Em cinco cães que morreram espontaneamente, além da excreção do CDV na urina, foram observadas alterações histopatológicas associadas à infecção por esse vírus. Análises estatísticas demonstraram que a idade, gênero, raça e o sistema orgânico comprometido dos cães avaliados não exerceram influência no diagnóstico da cinomose canina. Mioclonia e incoordenação motora foram as manifestações neurológicas que apresentaram frequência de ocorrência significativa (P<0,05). Uma associação direta foi observada entre a presença de ceratoconjuntivite e a identificação de virúria pelo CDV. Esses achados sugerem que a excreção do CDV pela urina em cães com sinais clínicos compatíveis com cinomose pode não ser relacionada com a idade do animal, e que animais sintomáticos podem apresentar manifestações clínicas atribuídas ao CDV, porém sem a caracterização de virúria por RT-PCR. Adicionalmente, análises filogenéticas sugerem que várias cepas de CDV podem estar circulando em populações caninas de áreas urbanas no Brasil.

Natalizumab treatment for multiple sclerosis: updates and considerations for safer treatment in JCV positive patients / Tratamento com Natalizumabe para esclerose múltipla: atualizações e considerações para um tratamento mais seguro em pacientes positivos para o VJC

Natalizumab is currently one of the best options for treatment of patients with Multiple Sclerosis who have failed traditional prior therapies. However, prolonged use, prior immunosuppressive therapy and anti-JCV antibody status have been associated with increased risk of developing progressive multifocal leukoencephalopathy (PML). The evaluation of these conditions has been used to estimate risks of PML in these patients, and distinct (sometimes extreme) approaches are used to avoid the PML onset. At this time, the biggest issue facing the use of Natalizumab is how to get a balance between the risks and the benefits of the treatment. Hence, strategies for monitor JCV-positive patients undergoing Natalizumab treatment are deeply necessary. To illustrate it, we monitored JCV/DNA in blood and urine of a patient receiving Natalizumab for 12 months. We also bring to discussion the effectiveness of the current methods used for risk evaluation, and the real implications of viral reactivation.

Natalizumabe é atualmente uma das melhores opções para o tratamento de pacientes com Esclerose Múltipla que não respondem aos tratamentos tradicionais. No entanto, o seu uso prolongado, o uso de terapia imunossupressora prévia e o status sorológico antivírus JC têm sido associados com o risco aumentado de desenvolvimento de Leucoencefalopatia Multifocal Progressiva (LEMP). A avaliação destas condições tem sido utilizada para estimar os riscos do desenvolvimento de LEMP nestes pacientes, e abordagens distintas (por vezes extremas) são empregadas para evitar o aparecimento dessa patologia. Atualmente, o grande desafio está em obter um equilíbrio entre os riscos e os benefícios do tratamento com Natalizumabe. Assim, é crucial desenvolver estratégias para monitorar pacientes portadores do vírus JC sob tratamento com Natalizumabe. A título de ilustração, pesquisamos o vírus no sangue e na urina de um paciente sob tratamento durante 12 meses. Também discutimos a eficácia dos métodos atualmente utilizados para avaliação de riscos e as implicações reais de reativação viral.

BKV-infection in kidney graft dysfunction

INTRODUCTION: BKV nephropathy (BKN) causes kidney graft loss, whose specific diagnosis is invasive and might be predicted by the early detection of active viral infection. OBJECTIVE: Determine the BKV-infection prevalence in late kidney graft dysfunction by urinary decoy cell (DC) and viral DNA detection in urine (viruria) and blood (viremia; active infection). METHODS: Kidney recipients with >1 month follow-up and creatinine >1.5 mg/dL and/or recent increasing >20 percent (n = 120) had their urine and blood tested for BKV by semi-nested PCR, DC searching, and graft biopsy. PCR-positive patients were classified as 1+, 2+, 3+. DC, viruria and viremia prevalence, sensitivity, specificity, and likelihood ratio (LR) were determined (Table 2x2). Diagnosis efficacy of DC and viruria were compared to viremia. RESULTS: DC prevalence was 25 percent, viruria 61.7 percent, and viremia 42.5 percent. Positive and negative patients in each test had similar clinical, immunossupressive, and histopathological characteristics. There was no case of viremia with chronic allograft nephropathy and, under treatment with sirolimus, patients had a lower viruria prevalence (p = 0.043). Intense viruria was the single predictive test for active infection (3+; LR = 2.8).1,6-4,9 CONCLUSION: DC, BKV-viruria and -viremia are commun findings under late kidney graft dysfunction. Viremia could only be predicted by intense viruria. These results should be considered under the context of BKN confirmation.

Viruria in Adult Hemorrhagic Cystitis Patients Following Allogeneic Hematopoietic Stem Cell Transplantation and Implication of Antiviral Treatment

BACKGROUND: Viruria is frequently detected in patients who have had hemorrhagic cystitis (HC) following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Urinary viruses, especially BK virus, have been suggested as a cause of HC following allo-HSCT, therefore antiviral therapy is emerging as a therapeutic approach for its treatment. METHODS: Adult HC patients who underwent allo-HSCT from January 2005 to March 2006 at a single institution were enrolled. We performed a PCR-based assay for BK virus, JC virus, and CMV virus in urine obtained from the patients to determine the incidence of viruria, and the type of virus detected in the urine, and the effect of treatment with cidofovir on HC. RESULTS: Of 155 patients that received allo-HSCT during the study period, 22 (14.2%) experienced HC. A viral study of urine obtained from 19 of these 22 patients revealed that 16 (84.2%) had viruria. Eleven patients had grade III-IV HC, 5 of which were treated with intravenous cidofovir. Three of the HC patients who underwent treatment responded to cidofovir, 1 had no response, and 1 had a complete response followed by recurrence. CONCLUSION: Most adult HC patients (84.2%) had viruria following allo-HSCT, however the response rate to antiviral therapy with intravenous cidofovir for the treatment of high grade HC (grade III-IV) was 80%. Therefore, antiviral therapy should be considered if high grade HC does not respond to hyperhydration and transfusional support.

BK Virus Detection by Polymerase Chain Reaction in Renal Transplant Recipients and Healthy Donors / 대한진단검사의학회지

BACKGROUND: BK virus is a polyomavirus associated with a range of clinical presentations from asymptomatic viruria with pyuria to ureteral ulceration with ureteral stenosis in renal transplant patients. BK viral Infection of renal allografts has been associated with diminished graft function in some individuals. We tried to detect BK virus in urine and plasma from Korean renal transplant recipients, renal transplant candidates, and healthy donors. METHODS: To detect BK virus in urine and plasma, we used PCR-RFLP (polymerase chain reaction and restriction fragments length polymorphism) with BamHI. The study was performed from 118 renal transplant recipients, 18 renal transplant candidates, and 25 healthy donors. RESULTS: BK virus DNAs were detected in 21.2% of urine and 0.9% of plasma from renal transplant recipients. BK virus DNA was detected in neither urine nor plasma from healthy donors and renal transplants candidates. Among a total of eight patients who were clinically suspected of having BK nephropathy, three were PCR positive for BK virus and two were decoy-cell cytology positive. Six patients were diagnosed as BK nephropathy by tissue pathology. Among them, BK virus was detected by PCR in urine from five patients, and decoy cells were shed from five patients, respectively. CONCLUSIONS: BK virus detection by polymerase chain reaction in urine may be a non-invasive and sensitive tool for diagnosing and monitoring BK nephropathy.