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

BACKGROUND: BK virus nephropathy (BKVN) has been increasingly recognized as an important cause of renal transplant dysfunction, but no specific antiviral therapy is currently available. Furthermore, a method evaluating the degree of viral infection has not been developed yet. Recently, there have been several case reports in which BKVN was successfully treated with cidofovir injection. In the current study, we report a case with BKVN successfully treated with cidofovir injection. In addition, we assessed the usefulness of quantitative viral load monitoring using a competitive polymerase chain reaction (PCR) in the treatment of BKVN. METHODS: A renal allograft recipient with BKVN was injected with cidofovir. To monitor BK viral load in urine and plasma, we developed a competitive PCR assay and followed the patient prospectively. RESULTS: A 49 year old renal transplant recipient developed a progressive rise in serum creatinine reaching 1.9 mg/dL at 15 months post-transplantation. Subsequently, the patient was diagnosed as BKVAN by allograft biopsy. At this time, BKV DNA was detected in plasma and urine. Despite a reduction of the dose of mycophenolate mofetil, serum creatinine continued to rise, which prompted the initiation of cidofovir trial. The patient was given intravenous cidofovir. After cidofovir treatment, BK virus associated findings disappeared on repeat biopsy, and BK virus in plasma was decreased to the undetectable level. For 7 months after cidofovir treatment, her renal function remained stable. CONCLUSION: Cidofovir therapy may be effective in the treatment for BKVN. Viral load in plasma reflected well the clinical and pathological course of the BK virus infection.
Allografts ; Biopsy ; BK Virus* ; Creatinine ; DNA ; Humans ; Middle Aged ; Plasma ; Polymerase Chain Reaction ; Prospective Studies ; Transplantation ; Viral Load*

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.
Allografts ; Biopsy ; BK Virus* ; Follow-Up Studies ; Humans ; Immunosuppression ; Mass Screening* ; Medical Records ; Retrospective Studies ; Transplant Recipients* ; Viremia