No abstract available.
BK Virus ; Kidney ; Transplant Recipients

No abstract available.
BK Virus ; Cystitis ; Encephalitis ; Hematopoietic Stem Cells ; Transplants

BK virus infection is one of the common complications after hematopoietic stem cell transplantation(HSCT), which is also one of the reasons of the hemorrhagic cystitis．In recent years, although there are more studies of the risk factors related with human BK virus infection after hematopoietic stem cell transplantation, the risk factors related with BKV-associated hemorrhagio cystitis(BKV-HC) remain to be elucidated. Diagnosis of BK virus infection is mainly based on quantitative PCR of blood or urine. An effective strategy for treatment of these patients is the adoptive transfer of T lymphocytes specific to virus-associated antigens. In this review, the progressis of diagnosis and treatment of BK virus infection after hematopoietic stem cell transplantation are briefly summarized.
BK Virus ; Cystitis ; Hematopoietic Stem Cell Transplantation ; Humans ; Polyomavirus Infections ; Tumor Virus Infections

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.
Adult* ; BK Virus ; Cystitis* ; Hematopoietic Stem Cell Transplantation* ; Hematopoietic Stem Cells* ; Humans ; Incidence ; JC Virus ; Recurrence

BACKGROUND: We evaluated the performance of a newly developed real-time polymerase chain reaction (PCR) method using TaqMan probe (TP) and internal control (IC) for quantitation of BK virus (BKV) DNA. METHODS: PCR primers and TP were targeted for the VP1 of BKV and 300 bp-region of VP1 was cloned to prepare a standard DNA. Threshold cycles (Ct) of IC was set at 33+/-3. The recovery rates, precision, linearity, and limit of detection (LOD) were measured using the standard DNA. To correlate TP with previous hybridization probe (HP) method, Ct of those were compared using 35 HP-positive and 15 HP-negative specimens, and the interpretation agreement was analyzed in 63 consecutive clinical specimens including 32 urines and 31 plasmas. Fifty-three53 specimens measured for IC were analyzed for positive rates and levels of BKV according to Ct of IC. RESULTS: The average recovery rate was 101.1% and intra-assay and inter-assay coefficiency variations were 0.017~0.059 and 0.036, respectively, with the specimens of 3 log/mL, and 0.041~0.063 and 0.045, respectively, with the specimens of 6 log/mL. LOD was 183 copies/mL and linearity range was 2.7 log- 12 log/mL. Ct of TP were correlated with those of HP with the function of y=0.8912x+0.3164 (R2=0.9062). Among 63 clinical specimens, 16 were positive in TP and 12 were positive in HP with an agreement of 90.4%. Ct of IC were over 36 in 31 specimens (22 urines and 9 plasmas), of which BKV DNA was much higher in 7 (22.5%) BKV-positive specimens (5.9+/-1.7 log/mL) than in 4 (18.1%) BKV-positive specimens (3.9+/-1.0 log/mL) of 22 having Ct of IC < or =36.; 5.9+/-1.7 vs. 3.9+/-1.0 log/mL. CONCLUSION: TP warrants to be a reliable method for quantification of BKV. IC seemed to be essential to differentiate false-negative results or underestimation of BKV in clinical specimens, especially in urine.
BK Virus* ; Clone Cells ; DNA* ; Limit of Detection ; Plasma ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction*

Despite the recent advances in immunosuppression, antibody mediated acute rejection is associated with a poor prognosis. Therapeutic interventions such as polyclonal antibodies, rituximab, and plasmapheresis have been used for the treatment of antibody mediated rejection. However, these treatments are associated with a serious infectious complication. Recently, Intravenous immunoglobulin (IVIG) are known to have powerful immunomodulatory effects on inflammatory and infectious disease. We successfully rescued two patients who had concomitant antibody mediated rejection and BK virus infection. IVIG could be a preferable choice for treatment of humoral rejection in the presence of infection.
Antibodies ; BK Virus* ; Communicable Diseases ; Humans ; Immunoglobulins ; Immunoglobulins, Intravenous* ; Immunosuppression ; Kidney Transplantation ; Plasmapheresis ; Prognosis ; Rituximab ; Transplantation*

BACKGROUND: Hemorrhagic cystitis(HC), a common complication of bone marrow transplantation(BMT), is known to be associated with toxic metabolites of chemotherapy drugs or reactivation of primary virus infections. In this study, we evaluated the association between polyomaviruria and HC in BMT patients. METHODS: Urine specimens of 29 patients with HC after BMT were requested for the detection of polyomavirus by culture and polyomerase chain reaction(PCR). Several clinical parameters were analyzed in relations to the presence of polyomaviruria. For comparison, 19 patients without HC after BMT were involved in this study. RESULTS: Overall, 45 of 558 patients developed HC after BMT, and the incidence of HC was estimated to be 8.1%. Patients group showed significantly high prevalence of BK viruria compared with control group by PCR(72.4% vs 31.6%, P = 0.005). In patients group, BK virus was isolated in 44.8%(13/29) by culture and detected in 72.4%(21/29) by PCR. Results of both methods were agreed in 65.5%(19/29). JC virus was detected in 6.9%(2/29) by PCR. Sex, conditioning regimen, graft-versus-host disease(GVHD), onset time after BMT and duration of hematuria did not show any statistically significant differences between the two groups based on the presence of BK viruria by PCR. CONCLUSIONS: High prevalence of BK viruria in HC patients after BMT suggests the possible association between BK virus and HC. However, we could not find any significant clinical parameters in association with BK viruria.
BK Virus ; Bone Marrow Transplantation ; Bone Marrow* ; Cystitis* ; Drug Therapy ; Hematuria ; Humans ; Incidence ; JC Virus ; Polymerase Chain Reaction ; Polyomavirus ; Prevalence

OBJECTIVE: To analyze the characteristics of BK polymavirus (BKV) infection and the optimal time window for intervention in kidney transplant recipients (KTRs). METHODS: We retrospectively analyzed the clinical data and treatment regimens in 226 KTRs in our center between January, 2013 and January, 2018. Among the recipients, 157 had a urine BKV load ≥1.0×10 copy/mL after transplantation, and 69 had a urine BKV load below 1.0×10 copy/mL (control group). RESULTS: Among the 157 KTRs, 60 (38.2%) recipients were positive for urine BKV, 66 (42.0%) had BKV viruria, and 31(19.7%) had BKV viremia. The incidence of positive urine occult blood was significantly higher in BKV-positive recipients than in the control group ( < 0.05). The change of urine BKV load was linearly related to that of Tacrolimus trough blood level (=0.351, < 0.05). In urine BKV positive group, the average estimated glomerular filtration rate (eGFR) was below the baseline level (60 mL·min·1.73 m) upon diagnosis of BKV infection reactivation, and recovered the normal level after intervention. In patients with BKV viruria and viremia, the average eGFR failed to return to the baseline level in spite of improvement of the renal function after intervention. CONCLUSIONS Positive urine occult blood after transplantation may be associated with BKV infection reactivation in some of the KTRs. BKV infection is sensitive to changes of plasma concentration of immunosuppressive agents. Early intervention of BKV replication in KTRs with appropriate dose reduction for immunosuppression can help to control virus replication and stabilize the allograft function.
BK Virus ; physiology ; Humans ; Kidney Transplantation ; Polyomavirus Infections ; virology ; Retrospective Studies ; Transplant Recipients ; Tumor Virus Infections ; virology ; Viral Load ; Virus Replication

PURPOSE:BK virus associated nephropathy (BKVAN) affects 1-10% of kidney transplant (KT) patients and it produces a progressive destruction of allograft. Reducing immunosuppression is the only way to save the graft, while it needs tight monitoring of the graft rejection and graft survival is poorer in advanced case. Leflunomide has immunosuppressive effect and also antiviral activity. Addition of leflunomide may improve BK virus clearance and graft survival. METHODS:6 KT patients with biopsy proven BKVAN (Histological pattern B) were treated with leflunomide and reduced immunosuppression. All patients were monitored with serial determination of viral load in blood and graft function. RESULTS:BKVAN was diagnosed at 14 months (7-28) post transplant, at that time median serum creatinine concentration was 2.8 mg/dL (1.8-3.6). 12.5 months (6-16) later of leflunomide treatment, median serum creatinine was 2.3 mg/dL and no graft loss was found. CONCLUSION:Leflunomide therapy with reduced immunosuppression may be effective in the treatment for BKVAN.
Biopsy ; BK Virus ; Creatinine ; Graft Rejection ; Graft Survival ; Humans ; Immunosuppression ; Isoxazoles ; Kidney ; Kidney Transplantation ; Transplantation, Homologous ; Transplants ; Viral Load ; Viruses

Hemorrhagic cystitis is a common stem cell transplantation-related complication. The incidence of early-onset hemorrhagic cystitis, which is related to the pretransplant conditioning regimen, has decreased with the concomitant use of mesna and hyperhydration. However, late-onset hemorrhagic cystitis, which is usually caused by the BK virus, continues to develop. Although the BK virus is the most common pathogenic microorganism of poststem cell transplantation late-onset hemorrhagic cystitis, pediatricians outside the hemato-oncology and nephrology specialties tend to be unfamiliar with hemorrhagic cystitis and the BK virus. Moreover, no standard guidelines for the early diagnosis and treatment of BK virus-associated hemorrhagic cystitis after stem cell transplantation have been established. Here, we briefly introduce poststem cell transplantation BK virus-associated hemorrhagic cystitis.
BK Virus ; Cell Transplantation ; Child ; Cystitis* ; Early Diagnosis ; Humans ; Incidence ; Mesna ; Nephrology ; Stem Cell Transplantation* ; Stem Cells ; Transplants