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-associated nephropathy (BKVN) is an important cause of chronic allograft dysfunction. The objective of our study was to evaluate the prognosis of BKVN. METHODS: We retrospectively reviewed the data of 133 renal transplant recipients with BKVN treated at the First Affiliated Hospital of Sun Yat-Sen University between July 2007 and July 2017. BK viral loads, graft function, and pathologic indexes were compared between initial diagnosis and last follow-up. RESULTS: After a mean follow-up period of 14.4 (range, 0.3-109.6) months after diagnosis of BKVN, BK viruria, and BK viremia become negative in 19.5% and 90.2% of patients, respectively. The mean estimated glomerular filtration rate (eGFR) at last follow-up was lower than at diagnosis of BKVN (18.3 ± 9.2 vs. 32.8 ± 20.6 mL·min·1.73 m, t = 7.426, P < 0.001). Eight (6.0%) patients developed acute rejection after reducing immunosuppression. At last follow-up, the eGFR was significantly lower in patients with subsequent rejection than those without (21.6 ± 9.8 vs. 33.5 ± 20.9 mL·min·1.73 m, t = 3.034, P = 0.011). In 65 repeat biopsies, SV40-T antigen staining remained positive in 40 patients and became negative in the other 20 patients. The eGFR (42.6 ± 14.3 vs. 26.5 ± 12.3 mL·min·1.73 m), urine viral loads (median, 1.3 × 10vs. 1.4 × 10 copies/mL), and plasma viral load (median, 0 vs. 0 copies/mL) were all significantly lower in patients with negative SV40-T antigen staining than those with persistent BK involvement (all, P < 0.05). Five (3.8%) recipients lost their graft at diagnosis of BKVN, and 13 (9.8%) lost their graft during the follow-up period. The 1-, 3-, and 5-year graft survival rates after diagnosis of BKVN were 99.2%, 90.7%, and 85.7%, respectively. Higher pathologic stage correlated with lower allograft survival rate (χ = 6.341, P = 0.042). CONCLUSION Secondary rejection and persistent histologic infection in BKVN lead to poor prognosis.
Adolescent ; Adult ; Aged ; BK Virus ; Child ; Female ; Glomerular Filtration Rate ; Graft Rejection ; Graft Survival ; Humans ; Kidney Diseases ; complications ; Kidney Transplantation ; adverse effects ; Male ; Middle Aged ; Polyomavirus Infections ; complications ; Retrospective Studies ; Viral Load ; Viremia ; complications ; Young Adult

BACKGROUND: Polyomavirus BK (BKV) infection is an important cause of graft loss in kidney transplant patients.PURPOSE: The purpose of this study was to evaluate clinical findings and risk factors for BKV in pediatric patients after kidney transplantation.METHODS: This retrospective single-center study included 31 pediatric kidney transplant recipients from January 2002 to December 2017. Two patients received 2 transplantations during the study period, and each transplant was analyzed independently. Total number of cases is 33 cases with 31 patients. BKV infection was confirmed from blood samples via periodic quantitative polymerase chain reaction.RESULTS: The mean age at kidney transplantation was 11.0±4.7 years, and the male-to-female ratio was 2.7:1. Three patients had a past medical history of high-dose chemotherapy and autologous stem-cell transplantation for solid tumors. Nine patients (27.3%) developed BKV infection. The median period from kidney transplantation to BKV detection in blood was 5.6 months. There was no statistically significant difference in estimated glomerular filtration rate between patients with and those without BKV infection. Among 9 patients with BKV viremia, 7 were treated by reducing their immunosuppressant dose, and BKV was cleared in 6 of these 7 patients. In the other 2 BKV-positive patients, viremia improved without immunosuppressant reduction.CONCLUSION: BKV infection is common in children with kidney transplantation and might not have affected short-term renal function in our patient sample due to early immunosuppressant reduction at the time of BKV detection.
BK Virus ; Child ; Drug Therapy ; Glomerular Filtration Rate ; Humans ; Kidney Transplantation ; Kidney ; Polymerase Chain Reaction ; Polyomavirus ; Retrospective Studies ; Risk Factors ; Transplant Recipients ; Transplants ; Viremia

No abstract available.
BK Virus ; Kidney ; Transplant Recipients

A 38-year-old man, who underwent a second kidney transplantation (KT), was admitted because of antibody-mediated rejection (AMR) complicated by BK virus-associated nephropathy (BKVAN). He was placed on hemodialysis at the age of 24 years because of membranoproliferative glomerulonephritis. At the age of 28 years, he underwent a living donor KT from his father; however, 1 year after the transplantation, he developed a recurrence of the primary glomerular disease, resulting in graft failure 2 years after the first KT. Ten years later, he received a deceased-donor kidney with a B-cell-positive-cross-match. He received 600 mg of rituximab before the KT with three cycles of plasmapheresis and immunoglobulin (0.5 g/kg) therapy after KT. During the follow-up, the first and second allograft biopsies at 4 and 10 months after KT revealed AMR with a recurrence of primary glomerular disease that was reclassified as C3 glomerulonephritis (C3GN). He received a steroid pulse, rituximab, plasmapheresis, and immunoglobulin therapies. The third allograft biopsy demonstrated that the BKVAN was complicated with AMR and C3GN. As the azotemia did not improve after repeated conventional therapies for AMR, one cycle of bortezomib (1.3 mg/m²×4 doses) was administered. The allograft function stabilized, and BK viremia became undetectable after 6 months. The present case suggests that bortezomib therapy may be applicable to patients with refractory AMR, even in cases complicated with BKVAN.
Adult ; Allografts ; Azotemia ; Biopsy ; BK Virus ; Bortezomib* ; Fathers ; Follow-Up Studies ; Glomerulonephritis* ; Glomerulonephritis, Membranoproliferative ; Graft Rejection ; Humans ; Immunization, Passive ; Immunoglobulins ; Kidney ; Kidney Transplantation ; Living Donors ; Plasmapheresis ; Recurrence ; Renal Dialysis ; Rituximab ; Transplants ; Viremia

Infectious complications have been considered as a major cause of morbidity and mortality after kidney transplantation, especially in the Asian population. Therefore, prevention, early detection, and prompt treatment of such infections are crucial in kidney transplant recipients. Among all infectious complications, viruses are considered to be the most common agents because of their abundance, infectivity, and latency ability. Herpes simplex virus, varicella zoster virus, Epstein–Barr virus, cytomegalovirus, hepatitis B virus, BK polyomavirus, and adenovirus are well-known etiologic agents of viral infections in kidney transplant patients worldwide because of their wide range of distribution. As DNA viruses, they are able to reactivate after affected patients receive immunosuppressive agents. These DNA viruses can cause systemic diseases or allograft dysfunction, especially in the first six months after transplantation. Pretransplant evaluation and immunization as well as appropriate prophylaxis and preemptive approaches after transplant have been established in the guidelines and are used effectively to reduce the incidence of these viral infections. This review will describe the etiology, diagnosis, prevention, and treatment of viral infections that commonly affect kidney transplant recipients.
Adenoviridae ; Allografts ; Asia ; Asian Continental Ancestry Group ; BK Virus ; Cytomegalovirus ; Diagnosis ; DNA Viruses ; Hepatitis ; Hepatitis B virus ; Herpesvirus 3, Human ; Humans ; Immunization ; Immunosuppression ; Immunosuppressive Agents ; Incidence ; Kidney Transplantation ; Kidney* ; Mortality ; Simplexvirus ; Transplant Recipients* ; Virus Diseases

BACKGROUND: The long-term prognosis of BK virus-associated nephropathy (BKVAN) in kidney transplant recipients (KTRs) is uncertain. We evaluated the long-term prognosis in KTRs with BKVAN and the clinical significance of BKVAN on post-transplant clinical outcome. METHODS: We retrospectively analyzed the medical records of 582 patients who underwent kidney transplant (KT) between 2001 and 2014. We divided the patients into a BKVAN group (15 patients) diagnosed by allograft biopsy and a control group (356 patients). RESULTS: The incidence of BKVAN was 4.0%, and the mean follow-up duration was 93.1 ± 52.3 months. Median time from KT to BKVAN diagnosis was 5.9 months (interquartile range [IQR], 4.4–8.7). In the BKVAN group, 9 (60.0%) KTRs with combined acute rejection progressed to graft failure, and the median time from BKVAN diagnosis to graft failure was 36.2 months (IQR, 9.7–65.5). Death-censored graft survival rate and patient survival rate in the BKVAN group were significantly lower than those in the control group. BKVAN and rejection were independent risk factors for graft failure. In the subgroup analysis, death-censored graft survival rate of KTRs with BKVAN with acute rejection was significantly worst in comparison with similar patients without BKVAN regardless of acute rejection (P < 0.001). CONCLUSION: The long-term prognosis of BKVAN with acute rejection was very poor because of graft failure caused by inadequate treatment for acute rejection considering BKVAN. Therefore, we should carefully monitor the allograft status of KTRs through regular surveillance tests after treatment for BKVAN with acute rejection.
Allografts ; Biopsy ; BK Virus ; Diagnosis ; Follow-Up Studies ; Graft Survival ; Humans ; Incidence ; Kidney Transplantation ; Kidney* ; Medical Records ; Prognosis* ; Retrospective Studies ; Risk Factors ; Survival Rate ; Transplant Recipients* ; 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: 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

PURPOSE: Additional clinical experience and knowledge regarding the barrier to transplantation of ABO blood type incompatibility could reduce the higher rate of infectious complications in ABO-incompatible kidney transplantation. METHODS: A total of 79 ABO-incompatible kidney transplantation (ABOiKT) patients were compared with 260 ABO-compatible kidney transplantation (ABOcKT) patients for basic clinical characteristics, infectious complications, rejection episodes, and graft survival. RESULTS: There were no significant differences in baseline characteristics, rejection rates, or graft survival between the ABOiKT and ABOcKT patients. No significant difference in the infection rate was shown for cytomegalovirus (26.6% vs. 30.0%; P = 0.672), BK virus (19.0% vs. 21.5%; P = 0.752), herpes disease (10.1% vs. 5.0%; P = 0.082), pneumonia (5.3% vs. 3.8%; P = 0.746), or urinary tract infection (8.9% vs. 10.0%; P > 0.999). Female sex (hazard ratio [HR], 2.20; P = 0.003), advanced age (≥60 years) (HR, 2.5; P = 0.019), history of rejection episodes (HR, 2.28; P = 0.016), and history of surgical complications (HR, 4.64; P = 0.018) were significant risk factors for infection. ABO incompatibility demonstrated a tendency toward higher infection risk without statistical significance (HR, 1.74; P = 0.056). CONCLUSION: In spite of immunosuppressant protocol modification, the rate of infectious complications following ABOiKT is still higher than with ABOcKT when a modified desensitization protocol is used. However, this was not sufficient to avoid ABOiKT.
BK Virus ; Cytomegalovirus ; Female ; Graft Survival ; Humans ; Kidney Transplantation ; Kidney* ; Pneumonia ; Risk Factors ; Transplant Recipients* ; Urinary Tract Infections