The risk of polyomavirus BK-associated hemorrhagic cystitis after allogeneic hematopoietic SCT is associated with myeloablative conditioning, CMV viremia and severe acute GVHD

Hyperbaric oxygen therapy improves the efficacy of conventional supportive treatment for late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation

OBJECTIVE

This study aims to investigate the efficacy and safety of hyperbaric oxygen therapy (HBOT) in the treatment of late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation.

METHODS

This retrospective analysis included 16 patients with late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation between 2016 and 2022. Among them, 8 patients received HBOT in addition to conventional treatment, while the other 8 received only conventional treatment. The clinical efficacy and safety of HBOT were evaluated by comparing the Numeric Rating Scale pain scores and clinical grades of hematuria before and after treatment, reflecting the patients' urinary pain and hematuria status.

RESULTS

The patients were divided into two groups based on whether they received HBOT. The group that received HBOT (n = 8) had a shorter duration of illness compared to the non-HBOT group (n = 8) (p < 0.05). The time for the NRS to decrease to below 2 was also shorter in the HBOT group. Furthermore, the patients who received HBOT did not experience any significant adverse reactions.

CONCLUSION

The combination of conventional treatment and hyperbaric oxygen therapy (HBOT) has been shown to improve symptoms such as urinary pain, frequency, urgency, and hematuria in patients with late-onset hemorrhagic cystitis after transplantation. This approach has been proven to be safe and effective.

Risk factors for mortality in children with hemorrhagic cystitis after hematopoietic transplant

INTRODUCTION

Hemorrhagic cystitis (HC) is a devastating complication of bone marrow (BMT) and stem cell transplant (SCT). Much of the literature has focused on exclusively adult patient populations, with limited evidence regarding risk factors for mortality and morbidity among pediatric HC patients.

OBJECTIVE

To examine factors associated with all-cause mortality in children with HC after BMT/SCT.

METHODS

The Pediatric Health Information System database was queried for patients with ICD-9/10 codes for hematopoietic transplant and gross hematuria, hematuria unspecified, or cystitis with hematuria. Multivariable logistic regression examined association of medical and surgical interventions frequently employed for hemorrhagic cystitis with mortality and genitourinary morbidity, defined as having received instillation of any bladder medication or having undergone any genitourinary procedure.

RESULTS

A total of 811 patients, mean age of 12.4 years and 62% male, were included. Primary diagnosis included 388 (49%) leukemia/lymphoma, 182 (22%) blood dyscrasia, 99 (12%) solid organ tumor, 27 (3%) metabolic disease, 115 (14%) unknown. Transplant type included 377 (46%) bone marrow, 329 (41%) stem cell, 105, and (13%) unknown. Performing any bladder instillation (p < 0.0001) or any type of GU procedure (p < 0.0001) was significantly associated with mortality. On multivariate analysis, dialysis (OR = 10.7, 95% CI = 5.7-20.2), genitourinary morbidity (OR = 4, 95% CI = 2.2-6.8) and intravenous cidofovir (OR = 2.0, 95% CI = 1.2-3.3) were significantly associated with all cause mortality. Having an underlying diagnosis of blood dyscrasia was protective against mortality (OR = 0.425, CI = 0.205-0.88).

DISCUSSION

In this large retrospective study evaluating factors associated with mortality in children with HC, all cause mortality was found to be 11%. This is probably an underrepresentation of true mortality in this population, as many patients discharged from the hospital likely die outside the hospital at home or hospice care. This study supports the current literature that invasive GU procedures are not associated with increased survival in patients with severe HC. This study is limited by retrospective use of a billing database that has the potential for errors in data entry and missing data. Patients who were discharged from the hospital were not captured by the PHIS which only collects data from inpatient stays.

CONCLUSIONS

Patients with HC who received dialysis, intravenous cidofovir, or underwent GU intervention had significantly higher all-cause mortality. High grade HC is a marker of disease severity and efforts should be made by urologists and oncologists to maximize quality of life and limit futile treatments in this patient population.

Decreased lymphocyte count before conditioning is associated with BK virus-associated hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation

BACKGROUND

BK virus-associated hemorrhagic cystitis (BKV-HC) is a serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). It can cause morbidity and may increase treatment-related mortality. Previous studies showed that the occurrence of BKV-HC was related to various factors. However, there are still many controversial factors. It is not clear whether BKV-HC will affect the long-term prognosis of patients.

OBJECTIVE

We aimed to identify risk factors for BKV-HC after allo-HSCT and evaluate the effect of BKV-HC on overall survival (OS) and progression- free survival (PFS) of patients.

STUDY DESIGN

We retrospectively analyzed the clinical data of 93 patients who underwent allo-HSCT. Univariate and multivariate analysis were used to identify risk factors for BKV-HC. The Kaplan-Meier method was used to estimate OS and PFS. A difference was considered statistically significant if P < 0.05.

RESULTS

A total of 24 patients developed BKV-HC. The median occurrence time of BKV-HC was 30 (range:8-89) days after transplantation, and the median duration was 25.5 (range:6-50) days. Multivariate logistic regression analysis indicated that peripheral blood lymphocyte count <1 × 10⁹/L before conditioning (OR = 4.705, P = 0.007) and haploidentical transplantation (OR = 13.161, P = 0.018) were independent risk factors for BKV-HC. The 3-year OS rate was 85.9% (95%CI:62.1%-95.2%) in the BKV-HC group and 73.1% (95%CI: 58.2%-88.0%) in the non-BKV-HC group. There was no significant difference between the two groups (P = 0.516). The 3-year PFS rate was 76.3% (95%CI: 57.9%-94.7%) in the BKV-HC group and 58.1% (95%CI: 39.5%-76.7%) in the non-BKV-HC group. There was no significant difference in the two groups (P = 0.459). The severity of BKV-HC was not related to the OS and PFS of the patients (P value was 0.816 and 0.501, respectively).

CONCLUSION

Haploidentical transplantation and decreased peripheral blood lymphocyte count before conditioning increased the risk of BKV-HC after allo-HSCT. The occurrence of BKV-HC after allo-HSCT and the severity of which did not affect OS and PFS of the patients.

Clinical study of late-onset hemorrhagic cystitis after allo-HSCT without in vitro T-cell depletion

This study is to investigate the hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) without in vitro T-cell depletion. Patients receiving allo-HSCT in 2019 were enrolled. The occurrence and clinical characteristics of HC after HLA-identical HSCT and haploidentical HSCT were retrospectively analyzed. BK, JC, cytomegalovirus, and other viruses were monitored when HC occurred. Conventional HC treatment was performed. Additionally, 5 cases of severe refractory HC were treated with adipose-derived mesenchymal stem cell (ADSC) besides conventional HC treatment. Totally, 54 patients with allo-HSCT were enrolled, including 12 cases with HLA-identical HSCT and 42 cases with haploidentical HSCT. Among them, 17 developed late-onset HC (LOHC). There was no early-onset HC. The median onset time was 33.5 (9-189) days, with a median duration of 19 (5-143) days. There were 8 cases of grade III HC and 2 cases of grade IV HC. The cumulative incidence of LOHC in 54 patients was 29.6%, and the cumulative incidence of LOHC in 42 patients with haploidentical HSCT was 40.5%. The 1-year expected progression-free survival (PFS) of 26 patients without HC was 86.6%, and the 1-year expected PFS of 16 HC patients was 74.5%. However, there was no statistically significant difference (P = .326). The urine BK virus of 14 patients was positive, with the lowest of 1.98 × 105 copies/mL, and the highest of 8.96 × 105 copies/mL. For the 5 patients with severe refractory HC, the lowest infusion dose of ADSC was 0.9 × 106/kg and the highest was 1.4 × 106/kg. All 5 patients were cured. The incidence of LOHC is higher after haploidentical HSCT. LOHC is positively correlated with urine BK virus. LOHC has no obvious effect on the overall PFS of patients. ADSC infusion has a good therapeutic effect on severe and prolonged LOHC.

Incidence of late-onset hemorrhagic cystitis and its effect on PFS in acute leukemia patients after haplo-PBSCT: The 5-year single-center data

We conducted a single-center 5-year retrospective study on the occurrence of hemorrhagic cystitis (HC) and its effect on survival after haploid high-dose peripheral blood stem cell transplantation (haplo-PBSCT) in patients with acute leukemia. We retrospectively analyzed 153 patients with acute leukemia who were treated with non-in vitro T-cell depleted haplo-PBSCT and myeloablative conditioning regimen. All patients were followed up for more than 180 days after transplantation. HC occurrence and its effect on long-term progression free survival (PFS) were retrospectively analyzed. Totally, 64 out of 153 patients had late onset HC (LOHC). No early onset HC occurred. The median onset time was 38.5 (17-163) days after transplantation. The cumulative incidence of LOHC was 41.8%. The cumulative incidence of LOHC in patients under 27 years old (50.0%) and in ALL patients (54.1%) was significantly higher than that in patients over 27 years old (34.5%) and in AML patients (36.9%), respectively. The cumulative incidence of mild LOHC was 44.2% and that of severe LOHC was 28.6%. However, urine copies of BK virus were not related to LOHC duration. There was no significant difference in 3-year expected PFS between AML and ALL patients with and without LOHC, or between LOHC duration more than and less than 38.5 days (P>0.05). Conclusively, LOHC incidence is higher in patients under 27 years old and in ALL patients. LOHC occurrence is related to urine BK virus copy, but not blood BK virus load. LOHC duration and severity has no significant effect on PFS.

Prognostic Value of Thrombocytopenia in Myelodysplastic Syndromes After Hematopoietic Stem Cell Transplantation

Prolonged isolated thrombocytopenia (PT) is a common complication affecting the outcome of stem cell transplantation. In this study, we undertook a real-world study of 303 myelodysplastic syndrome (MDS) patients who received allogeneic hematopoietic stem cell transplantation (HSCT) between December 2007 and June 2018. 28.4% of MDS patients suffered from PT after HSCT. Survival analysis indicated that PT was associated with worse overall survival (OS) in MDS patients. The 2-year and 5-year OS in MDS patients with PT after HSCT were 49% and 47%, significantly worse than that of 68% and 60% in patients without PT (P=0.005). For RFS, patients with PT did not have an increased risk of disease relapse (P=0.964). After multivariate adjustment, PT was proved to be the independent risk factor associated with the worse OS (HR 1.49, 95% CI 1.00-2.21, P =0.048). We further analyzed risk factors associated with the occurrence of PT in MDS patients. Multiple logistic regression identified grade II-IV aGVHD, extensive chronic GVHD, hemorrhagic cystitis, and CMV activation as significant risk factors for developing PT. Among these variables, the Odds Ratio (OR) of grade II-IV aGVHD was the highest (P =0.001, OR: 2.65, 95% CI: 1.51-4.64). These data indicated the prognostic value of PT in MDS after HSCT. The identification of risk factors for PT may help improve patient management and lead to the design of effective treatment strategies.

Pentosan polysulfate for the treatment of hemorrhagic cystitis after allogeneic hematopoietic cell transplant

INTRODUCTION

Hemorrhagic cystitis can commonly occur following an allogeneic hematopoietic cell transplant and treatment options are currently limited. Pentosan polysulfate, a heparin-like, sulfated polysaccharide, is used to relieve bladder pain and discomfort associated with interstitial cystitis. Initial reports in patients with hemorrhagic cystitis demonstrate that pentosan polysulfate may hasten hemorrhagic cystitis resolution and control symptoms.

METHODS AND RESULTS

This report includes a retrospective case series of six patients who received pentosan polysulfate for the treatment of hemorrhagic cystitis following an allogeneic hematopoietic cell transplant. Pentosan polysulfate was initiated at a median of 4.5 days (range: 3-18) following hemorrhagic cystitis onset and continued for a median duration of 17.5 days (range: 7-64). Four patients were tested for BK virus and all were found to have BK viremia and viruria around the time of pentosan polysulfate initiation. The median number of red blood cell transfusions seemed to decrease in the patients initiated on pentosan polysulfate. All patients received a multi-agent treatment regimen, which included pentosan polysulfate, and half the patients had symptom resolution. The median time to symptom resolution from pentosan polysulfate initiation was 9 days (range: 7-10).

CONCLUSION

Pentosan polysulfate was well-tolerated and seemed to assist with symptom resolution. Future studies are needed to confirm the impact of pentosan polysulfate on the treatment of hemorrhagic cystitis.

Effect of late-onset hemorrhagic cystitis on PFS after haplo-PBSCT

Introduction

This study is to investigate the effect of late-onset hemorrhagic cystitis (LOHC) on progression-free survival (PFS) of patients after haploidentical peripheral blood hematopoietic stem cell transplantation (haplo-PBSCT).

Methods

This retrospective study enrolled 74 patients with hematological malignancies treated with a myeloablative conditioning regimen and haplo-PBSCT. The effect of LOHC on PFS was studied in terms of HC occurrence, grade, disease type, duration, onset time, gender, and age.

Results

There were 28 patients with LOHC, and no case was with early-onset HC. The cumulative incidence of LOHC was 37.8% (95% CI: 26.9–48.7%). The 2-year expected PFS of 74 patients and 34 AML patients was not significantly different between LOHC patients and patients without HC (P > 0.05). Among 27 ALL patients, the 2-year expected PFS of LOHC patients was 75%, significantly higher than patients without HC (54.2%) (P < 0.05). The 2-year expected PFSs of patients with mild LOHC and severe LOHC were 69.8 and 77.8%, respectively (P > 0.05). Similarly, the onset time, duration, age, and gender of LOHC patients did not show significant effects on PFS (P > 0.05).

Conclusions

After haplo-PBSCT, LOHC has a significant effect on the PFS of ALL patients. The HC grade, duration, onset time, gender, and age have no significant effect on PFS.

Pretransplant BK Virus-Specific T-Cell-Mediated Immunity and Serotype Specific Antibodies May Have Utility in Identifying Patients at Risk of BK Virus-Associated Haemorrhagic Cystitis after Allogeneic HSCT

BK polyomavirus (BKPyV) persists lifelong in renal and urothelial cells with asymptomatic urinary shedding in healthy individuals. In some immunocompromised persons after transplantation of hematopoietic stem cells (HSCT), the BKPyV high-rate replication is associated with haemorrhagic cystitis (HC). We tested whether the status of BKPyV immunity prior to HSCT could provide evidence for the BKPyV tendency to reactivate. We have shown that measurement of pretransplant anti-BKPyV 1 and 4 IgG levels can be used to evaluate the HC risk. Patients with anti-BKPyV IgG in the range of the 1st-2nd quartile of positive values and with positive clinical risk markers have a significantly increased HC risk, in comparison to the reference group of patients with "non-reactive" anti-BKPyV IgG levels and with low clinical risk (LCR) (p = 0.0009). The predictive value of pretransplant BKPyV-specific IgG was confirmed by determination of genotypes of the shed virus. A positive predictive value was also found for pretransplant T-cell immunity to the BKPyV antigen VP1 because the magnitude of IFN-γ T-cell response inversely correlated with posttransplant DNAuria and with HC. Our novel data suggest that specific T-cells control BKPyV latency before HSCT, and in this way may influence BKPyV reactivation after HSCT. Our study has shown that prediction using a combination of clinical and immunological pretransplant risk factors can help early identification of HSCT recipients at high risk of BKPyV disease.

A cluster of BK polyomavirus-associated hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation

BACKGROUND

BK polyomavirus (BKV) can cause hemorrhagic cystitis (HC) in immunocompromised patients after hematopoietic stem cell transplantation (HSCT). It remains unclear whether nosocomial BKV infections occur. During a 9-month period, an increase in BKV-associated HC (BKV-HC) cases was observed at our institution.

AIM

The BKV-HC cluster population was compared with populations of HSCT patients from before and after the BKV-HC cluster to evaluate whether nosocomial BKV transmission had occurred.

METHODS

A retrospective analysis was carried out to assess the risk of patients developing BKV-HC after HSCT. The background data of the cluster patients were compared with those of the patients who underwent HSCT before or after the cluster, and the collected BKV isolates were serotyped.

RESULTS

BKV-HC involving grade ≥2 hematuria occurred in six of 15 HSCT recipients during a 9-month period. The incidence of BKV-HC was significantly higher in this period than in the other periods (p = 0.0014). There were no significant differences in the patients' background data between the cluster and non-cluster periods, including in terms of risk factors for BKV-HC. Serotype analyses of BKV revealed that the BKV detected in the urine samples from four of the six BKV-HC patients belonged to subtype Ic. The gene sequences of these four BKV exhibited >99.5% homology.

CONCLUSION

Our study suggests that nosocomial BKV infections may occur after HSCT. Although many cases of BKV-HC are caused by the reactivation of a latent virus, it is necessary to employ appropriate hygiene measures when cases of BKV-HC occur.

Incidence and risk factors of late-onset hemorrhagic cystitis after single umbilical cord blood transplantation with myeloablative conditioning regimen

OBJECTIVE

To explore the incidence and risk factors of late-onset hemorrhagic cystitis (LOHC) in patients undergoing single umbilical cord blood transplantation for hematological malignancies.

METHODS

Clinical data from 234 patients who consecutively underwent single UCBT using a myeloablative conditioning regimen without antithymocyte globulin in our center were retrospectively analyzed.

RESULTS

In total, 64 (27.4%) patients developed LOHC with a median onset time of 40.5 (range 8-154) days, and 15 (6.4%) patients gradually developed grade III-IV LOHC. The incidence of LOHC was marginally higher in adults (31.0%) than in children (23.7%) (p = 0.248). HLA matching ≤ 6/8 (HR = 2.624, 95% CI 1.112-6.191, p = 0.028) was an independent risk factor for LOHC. The overall survival of LOHC patients (59.8%, 95% CI 61.7-85.5%) was significantly lower than that of patients without LOHC (86.8%, 95% CI 79.6-91.6%) at 130 days post transplantation (p = 0.036).

CONCLUSION

Patients with less well-matched grafts have a higher incidence of LOHC. Inherent deficiencies in immunity in the context of HLA disparity and more intense pharmacologic immunosuppression after severe acute graft-versus-host disease may contribute to viral activation. Prevention and treatment of LOHC have the potential to prolong long-term survival.

Post-allogeneic hematopoietic stem cell transplantation viral reactivations and viremias: a focused review on human herpesvirus-6, BK virus and adenovirus

Human cytomegalovirus and Epstein-Barr virus have been recognized as potential drivers of morbidity and mortality of patients undergoing allogeneic stem cell transplantation for years. Specific protocols for monitoring, prophylaxis and pre-emptive therapy are in place in many transplant settings. In this review, we focus on the next three most frequent viruses, human herpesvirus-6, BK virus and adenovirus, causing reactivation and/or viremia after allogeneic transplant, which are increasingly detected in patients in the post-transplant period owing to emerging techniques of molecular biology, recipients' characteristics, treatment modalities used for conditioning and factors related donors or stem cell source. Given the less frequent detection of an illness related to these viruses, there are often no specific protocols in place for the management of affected patients. While some patients develop significant morbidity (generally older), others may not need therapy at all (generally younger or children). Furthermore, some of the antiviral therapies used are potentially toxic. With the addition of increased risk of secondary infections, risk of graft failure or increased risk of graft-versus-host disease as well as the relationship with other post-transplant complications, the outcomes of patients with these viremias remain unsatisfactory and even long-term survivors experience increased morbidity.

Presentation of BK polyomavirus-associated hemorrhagic cystitis after allogeneic hematopoietic cell transplantation

BK polyomavirus (BKPyV) has been associated with hemorrhagic cystitis (HC) after allogeneic hematopoietic cell transplantation (HCT), but the natural history of HC and factors associated with the clinical course are incompletely understood. We retrospectively analyzed allogeneic HCT patients transplanted from 2007-2017 who presented after platelet engraftment or after day 28 post-HCT with BKPyV-associated HC (BKPyV-HC), which was defined as a positive urine BKPyV PCR, ≥1 plasma BKPyV viral load result, and macroscopic hematuria (Bedi grade ≥2). Factors associated with resolution of macroscopic hematuria and resolution of all cystitis symptoms within 90 days after HC diagnosis were investigated in multivariable models. In 128 patients with BKPyV-HC, the median times from diagnosis to resolution of all symptoms, macroscopic hematuria, and urinary clots (present in 55% [71/128]) were 24 days (15-44), 17 days (10-30), and 14 days (5-26), respectively. Ninety percent of patients had BKPyV viremia at the onset of HC with a median viral load of 1850 copies/mL (interquartile range, 240-8550). In multivariable models, high plasma viral load (≥10 000 copies/mL) and cytopenias at the beginning of BKPyV-HC were significantly associated with longer macroscopic hematuria and cystitis symptoms. Use of cidofovir was not associated with shorter duration of illness. In conclusion, BKPyV-HC after allogeneic HCT is characterized by prolonged and severe symptoms and requires improved management strategies. High-grade viremia and cytopenias were associated with a longer duration of BKPyV-associated HC. Accurate descriptions of disease and factors associated with prolonged recovery will inform end points of future clinical trials.

BK Virus Epidemiology, Risk Factors, and Clinical Outcomes: An Analysis of Hematopoietic Stem Cell Transplant Patients at Texas Children's Hospital

BACKGROUND

BK virus-associated hemorrhagic cystitis (BKV-HC) is a serious complication after hematopoietic stem cell transplantation (HSCT).

METHODS

A retrospective review was performed to determine the frequency of BKV-HC and identify risk factors and renal morbidity associated with BKV-HC in pediatric HSCT recipients at our institution.

RESULTS

A total of 314 pediatric recipients underwent allogeneic HSCT for either malignant (173, 55.1%) or nonmalignant disorders (141, 44.9%) from January 1, 2011, to December 31, 2015, with a minimum follow-up of 5 years post-HSCT. Severe BKV-HC (grades 3 and 4) was prevalent in 46 out of 67 (68.7%) recipients. Timing to presentation of severe BKV-HC (grades 3 and 4) occurred at a median of 37 days (26, 74; IQ1, IQ3) post-HSCT, with the duration of macroscopic hematuria lasting a median of 37.5 days (18, 71; IQ1, IQ3). In the first 60 days post-HSCT, peak acute kidney injury (AKI) stages 2 and 3 were seen more frequently in HSCT recipients who developed BKV-HC than those without (P = .004). Similarly, during post-HSCT days 61 to 100, peak AKI stage 3 was also more frequently seen in HSCT recipients who already developed BKV-HC prior to or during this time period than those without BKV-HC (P = .0002). Recipients who developed BKV-HC within 1 year of HSCT had more frequent mild to moderate chronic kidney disease (CKD stages 2-3) than those without BKV-HC (P = .002 and .007, respectively). On multivariate analysis, BKV-HC was associated with all-cause mortality (hazard ratio [HR]: 2.22; 95% confidence interval [CI]: 1.35-3.65). The following clinical variables were associated with time to development of HC on multivariate analysis: age (subdistribution HR [sHR] 1.11; 95% CI: 1.06-1.16) and myeloabalative conditioning regimen (sHR 4.2; 95% CI: 2.12-8.34).

CONCLUSIONS

Pediatric HSCT patients with BKV-HC experience significant morbidity and mortality. Renal morbidity, including AKI and CKD, is associated with BKV-HC.

Risk factors of BK viral hemorrhagic cystitis in allogenic hematopoietic stem cell transplantation

Reactivation of BK virus (BKV) can occur during intensive immunosuppression such as in allogenic hematopoietic stem cell transplant (AHSCT) recipients for whom a systematic PCR urine test for BKV will be positive in 50% to 100% of patients. Only 5% to 40% will develop BKV hemorrhagic cystitis (HC). Thus, BKV PCR testing is useful to confirm a diagnosis of BKV-HC but not to predict its occurrence. The aim of this retrospective study was to ascertain the risk factors of developing BKV HC, mostly in patients receiving posttransplant cyclophosphamide. The study looked at data from Grenoble Alpes University Hospital included in the national retrospective register ProMISe, administered by the "Société Francophone de Greffe de Moelle et de Thérapie Cellulaire". Urine BKV PCR was performed when patients presented grade ≥ 2 hematuria with clinical symptoms of cystitis. BKV-HC was defined as an association of clinical symptoms of cystitis, grade ≥ 2 hematuria and BKV viruria > 7 log₁₀ copies/ml. From January 2014 to January 2018, 168 AHSCTs were considered for analysis, of which 43 (25.6%) developed BKV-HC and 44.9% of the subgroup that received posttransplant cyclophosphamide. After logistic regression, the risk factors associated with BKV-HC were reduced to posttransplantation exposure to cyclophosphamide (OR 4.25, [1.66; 10.87], P = .02), age < 40 y (OR 3.85 [1.51; 9.80], P = .005) and corticosteroid therapy (OR 3.86, [1.59; 9.36], P = .003). Exposure to cyclophosphamide, younger age (<40) and corticosteroid therapy are potential risk factors for BKV-HC.

Prospective analysis of BKV hemorrhagic cystitis in children and adolescents undergoing hematopoietic cell transplantation

BK virus is one of the most common causes of hemorrhagic cystitis (HC) in children undergoing hematopoietic cell transplantation (HCT). Viruses can be found in urine and serum samples of immunocompromised patients. Malignant diseases, age, cell source, day of granulocyte reconstitution, conditioning regimen, or use of total body irradiation may play an important role in BKV epidemiology, development of hemorrhagic cystitis course, and outcome. The aim of this study was to evaluate the incidence, clinical course, and risk factors for BKV-HC in children undergoing HCT. A total number of 133 patients who were prospectively tested for BKV colonization/infection were enrolled into this multicenter analysis. Episodes of BKV-HC occurred in 36/133 (27%) enrolled subjects. In a univariate analysis for BKV-HC incidence, the following factors were significant: age >5 years, peripheral blood transplantation, matched unrelated donor (MUD) transplantation, busulfan-cyclophosphamide-melphalan conditioning regimen, and acute myeloblastic leukemia (AML) diagnosis. Presence of acute graft-versus-host disease (aGVHD) in liver and gut GVHD was a significant risk factor of BKV-HC. No BKV-attributed deaths were reported. In multivariate analysis, the incidence of HC was significantly higher in patients with AML, age >5 years, MUD transplants, and children with GVHD. HC is a frequent complication after HCT among children causes prolonged hospitalization but rarely contributes to death. We identified risk factors of BKV-HC development in children, with focus on aGVHD: we concluded that excessive immune reaction connected with GVHD and immunosuppression drugs might play a pivotal role in the development of BKV-HC.

BK virus encephalitis and end-stage renal disease in a child with hematopoietic stem cell transplantation

BK virus encephalitis after HSCT is uncommon. Several reports of native kidney BKVN in patients with HSCT, hematologic malignancies, human immunodeficiency virus infection, and non-renal solid organ transplantation have been described. However, an uncommon combination of BK encephalitis and ESRD of native kidneys secondary to BK virus in a child with HSCT has not been described. We report a 10-year-old boy who presented with a gradually rising serum creatinine during treatment for severe autoimmune hemolytic anemia, which he developed 9 months after receiving an allogeneic HSCT for aplastic anemia. There was no proteinuria or hematuria present. Serum BK virus load was 5 × 10⁶  copies/mL. A renal biopsy showed evidence of BKVN. He developed fever, seizures, and confusion, and the (CSF) showed significant presence of the BK virus (1 × 10⁶  copies/mL) along with biochemical evidence of viral encephalitis. Cerebrospinal fluid cultures were negative. Despite significant clinical symptoms and presence of BK virus in CSF, the magnetic resonance brain imaging findings were minimal. With reduction of immunosuppression, there was resolution of BK encephalitis but BKVN remained resistant to multiple anti-BK virus agents, including leflunomide and cidofovir. He eventually became dialysis-dependent and, 6 years later, received a renal transplant from his mother. This case illustrates that BK virus in severely immunocompromised HSCT recipient may lead to BK encephalitis and BKVN of native kidneys, even without hemorrhagic cystitis, leading to ESRD. Knowledge of such is important for appropriate timely evaluation and management.

BK virus infection in allogeneic hematopoietic cell transplantation: An update on pathogenesis, immune responses, diagnosis and treatments

In hematopoietic cell transplantation (HCT) patients, BK polyomavirus (BKPyV) infection results in significant morbidity mainly due to hemorrhagic cystitis (HC). Despite increased knowledge acquired over recent decades, no treatment has shown effectiveness in the management of organ damage in HCT allografts. This review summarizes the current knowledge on BKPyV, from the virus constitution to the pathophysiology and immune-related mechanisms. We next focus on BKPyV-induced HC in HCT to discuss the benefit of monitoring BKPyV viruria and viremia in the management of patients. At last, we review currently used therapeutics, along with future promising therapies to propose clinical and practical guidelines and further interesting research areas.

Effects and long-term follow-up of using umbilical cord blood-derived mesenchymal stromal cells in pediatric patients with severe BK virus-associated late-onset hemorrhagic cystitis after unrelated cord blood transplantation

This is a retrospective study to evaluate the efficacy and safety of umbilical cord blood-derived mesenchymal stromal cells (MSCs) for the treatment of pediatric patients with severe BK virus-associated late-onset hemorrhagic cystitis (BKV-HC) after unrelated cord blood transplantation (UCBT). Thirteen pediatric patients with severe BKV-HC from December 2013 to December 2015 were treated with MSCs. The number of MSCs transfused in each session was 1 × 10⁶ /kg once a week until the symptoms improved. The median follow-up time was 1432 (89-2080) days. The median frequency of MSC infusion was 2 (1-3), with eight cured cases and five effective cases; the total efficacy rate was 100%. The copy number of urine BKV DNA was 4.43 (0.36-56.9) ×10⁸ /mL before MSC infusion and 2.67 (0-56.3) ×10⁸ /mL after MSC infusion; the difference was not significant (P = .219). There were no significant differences in the overall survival, disease-free survival, and the incidence of relapse and acute and chronic graft-versus-host disease between the MSC infusion group and non-MSC infusion group. There was also no significant difference in the cytomegalovirus, Epstein-Barr virus (EBV), and fungal and bacterial infection rates between the two groups. Although umbilical cord blood-derived MSCs do not reduce the number of BKV DNA copies in the urine, the cells have a high efficacy rate and minimal side effects in treating severe BKV-HC after UCBT among pediatric patients. MSCs do not affect the rates of relapse, long-term infection, or survival of patients with leukemia.

Impact of extended infusional mesna prophylaxis on the incidence of BK viruria and hemorrhagic cystitis following post-transplantation cyclophosphamide and CTLA4Ig-based haploidentical transplantation

Hemorrhagic cystitis (HC) has been reported with increased frequency following post-transplantation cyclophosphamide (PTCy)-based haploidentical hematopoietic cell transplantation (HCT) along with a strong association with BK viruria. We prospectively evaluated the incidence of BK viruria and HC in 115 patients (median age 20 years, 2-65) undergoing PTCy-based haploidentical HCT with (n = 71) or without (n = 44) CTLA4Ig. HC prophylaxis consisted of a continuous infusion of mesna 30 min prior and 48 h post-PTCy. The overall incidence of BK viruria was 65.7%. None with BK viruria < 10⁴ copies/ml developed clinical symptoms (n = 65). The incidence of BK viruria ≥ 10⁴ copies/ml was 7.1% (n = 8) and 75% developed HC. The incidence of HC was 5.4% at a median of 30 days. Both BK viruria ≥ 10⁴ copies/ml and HC were strongly associated with acute GVHD (p < 0.001). A higher NRM was observed in those with BK viruria ≥ 10⁴ copies/ml, related to GVHD and its complications (41.7% vs 12.6%, p = 0.04). The incidences of acute GVHD, vis-à-vis, overall BK viruria, BK viruria ≥ 10⁴ copies/ml, and HC, tended to be lower in patients receiving CTLA4Ig. Thus, extended infusional mesna, coupled with significant reduction in alloreactivity along with possible preservation of antiviral immunity associated with the use of CTLA4Ig, was probably responsible for a much lower incidence of BK viruria and resultant HC than reported previously following PTCy-based haploidentical HCT.

Reactivation of BK virus after double umbilical cord blood transplantation in adults correlates with impaired reconstitution of CD4+ and CD8+ T effector memory cells and increase of T regulatory cells

BK virus (BKV), a human polyomavirus that remains latent in renal epithelial cells, can be reactivated after hematopoietic stem cell transplantation (HSCT) leading to hemorrhagic cystitis. The incidence of BK viremia is higher after Umbilical cord blood transplantation (UCBT) than HSCT from adult donors. Data regarding the role of immune recovery after UCBT in BKV reactivation is lacking. We examined the correlation between the development of BK viremia and immune reconstitution in 27 adult recipients of UCBT. The incidence of BK viremia was 52% and developed most frequently within the first 8 weeks after the transplantation, but persisted in seven patients at 6 months, and three patients at 1-year post UCBT. Detection of BK viremia 1 year after transplant was negatively associated with the number of CD8⁺ cells (p = 0.03) and CD8⁺CD45RO⁺ cells (p = 0.05) at 6 months, and the number of CD4⁺ (p = 0.03) and CD4⁺CD45RO⁺ cells (p = 0.03) at 12 months after UCBT. Conversely, BK viremia at 6 and 12 months was positively correlated with the number of T regulatory (Treg) cells at 1 month (p = 0.005 and p = 0.016, respectively). Because UCB Treg have highly potent immunosuppressive function, our findings indicate that sustained BK viremia in UCBT recipients might be associated with the increase of Treg cells early after transplantation, which mediate impaired and delayed reconstitution of CD4⁺ and CD8⁺ T effector cells.

Complications of Stem Cell Transplantation that Affect Infections in Stem Cell Transplant Recipients, with Analogies to Patients with Hematologic Malignancies

This article discusses the complications of hematopoietic stem cell transplantion (HSCT) that affect infections in HSCT recipients, with analogies to patients with hematologic malignancies. Mucositis, with mucosal barrier disruption, is common and increases the risk of gram-positive and anaerobic bacterial, and fungal infections, and can evolve to typhlitis. Engraftment syndrome; graft-versus-host disease, hepatic sinusoidal obstruction syndrome; and posterior reversible encephalopathy syndrome can affect the infectious potential either directly from organ dysfunction or indirectly from specific treatment. Pulmonary infections can predispose to life threatening complications including diffuse alveolar hemorrhage, idiopathic pulmonary syndrome, bronchiolitis obliterans syndrome, and bronchiolitis obliterans with organizing pneumonia.

[Application of multiplex PCR assay to study early multiple herpesviruses infection during HSCT]

Objective: To investigate herpesvirus infection in early stage of hematopoietic stem cell transplantation (HSCT) by multiplex polymerase chain reaction (PCR), and to explore the association between multiple herpesviruses infection and clinical characteristics in HSCT patients and its impact on post-transplant complications and prognosis. Methods: A total of 734 peripheral blood samples were collected from 90 patients undergoing HSCT in the Department of Hematology, the First Affiliated Hospital of Soochow University between February 2017 and August 2017. The peripheral blood specimens were obtained before and within 90 days after transplantation at different time points. Lab-Aid824 Nucleic Acid Extraction Mini Reagent was used to extract DNA and multiplex PCR assay was used to simultaneously detect 8 kinds of human herpesviruses from genomic DNA. The incidence of various herpesvirus infections, its correlation with clinical features and effects on post-transplant complications and prognosis were analyzed. Results: The median follow-up time was 192 (range: 35-308) days. Among the 90 patients before transplantation, the incidence of herpes virus infection was 35.6% (32/90), including 12.2% (11/90) with one herpes virus infection and 23.3% (21/90) with multiple viruses infection. The incidence of herpes virus infection after transplantation was 77.8% (70/90), including 20.0% (18/90) with one herpes virus infection and 57.8% (52/90) with multiple herpes virus infection. Among the 52 patients with multiple herpes viruses infection, 30 (57.7%) patients were infected by 2 kinds of viruses, 18 (34.6%) patients by 3 kinds of viruses and 4 (7.7%) patients by 4 kinds of viruses. There was a correlation between HHV-6 and HHV-7 herpesvirus infection (OR=13.880, Q=0.026). EBV infection was related to HHV-7 infection (OR=0.093, Q=0.044). The age of patients was correlated with the incidence of HHV-1 infection before transplantation. There were 24 patients in our study experienced clinical symptoms associated with viral infection. The main manifestations were hemorrhagic cystitis (HC), interstitial pneumonia, enteritis, viral encephalitis and fever of unknown origin. EBV infection was related to HLA incompatibility and the inconsistent of the ABO blood group and grade Ⅱ-Ⅳ aGVHD after transplantation. HLA incompatibility and the unrelated donor and grade Ⅱ-Ⅳ aGVHD were related to multiple viruses infection. Conclusion: Multiple herpesviruses were common in patients undergoing HSCT, which were closely related to HLA mismatch, unrelated donor and grade Ⅱ-Ⅳ aGVHD.

High incidence of BK virus-associated hemorrhagic cystitis in children after second or third allogeneic hematopoietic stem cell transplantation

BKV-HC is a serious complication of allogeneic HSCT. To characterize the incidence, risk factors, and clinical outcomes of post-HSCT BKV-HC, we retrospectively analyzed 112 patients who underwent one or more allogeneic HSCTs at our hospital between 2001 and 2017. Twenty underwent second or third HSCT thereafter. Ten patients developed BKV-HC at a median of 30 days after HSCT. The 100-day cumulative incidences of grade 0-4 and grade 2-4 BKV-HC were 7.8% and 6.2%, respectively. HSCTs performed in 2011-2017 associated with significantly higher 100-day cumulative incidence of grade 2-4 BKV-HC (14.0%) than HSCTs performed in 2001-2010 (1.3%, P = 0.004). On multivariate analysis, second or third HSCT was the only independent significant risk factor for development of grade 2-4 BKV-HC (P = 0.015). Serial PCR monitoring of urine and blood BKV load did not predict BKV-HC. The recent increase in the incidence of BKV-HC may reflect recent innovations in transplant technologies that facilitate second or third HSCT, which are known to cause prolonged immune deficiency. If safe and effective treatment or prophylaxis becomes available, it could be used to target the high-risk patients for BKV-HC.

Comparison of Different Conditioning Regimens of Haploidentical Hematopoietic Stem Cell Transplant in Patients With Acute Myeloid Leukemia

OBJECTIVES

We evaluated the safety and efficacy of 2 conditioning regimens (busulfan/fludarabine vs modified busulfan/cyclophosphamide) in patients with acute myeloid leukemia undergoing haploidentical hematopoietic stem cell transplant.

MATERAILS AND METHODS

Twenty patients with primary acute myeloid leukemia had been randomized into busulfan/fludarabine and modified busulfan/cyclophosphamide groups. We retrospectively compared hematopoietic engraftment, regimen-related toxicity, graft-versus-host disease, transplant-related mortality, leukemia-free survival, and overall survival between the groups.

RESULTS

All patients achieved engraftment with 100% donor chimerism. The median times for the neutrophil and platelet engraftment in the busulfan/fludarabine and modified busulfan/cyclophosphamide groups were 14.1 versus 14.3 days and 12.7 versus 12.2 days, respectively. Significantly lower incidences of pretreatment toxicity, blood transfusion, and virus activation were observed in the busulfan/fludarabine group. Acute grade 1 graft-versus-host-disease developed in all patients, which was successfully controlled with methylprednisolone. There were no significant differences in engraftment, graft-versus-host disease, leukemia-free survival, and overall survival between groups. Both of these conditioning regimens achieved stable engraftment. Regimen-related toxicity in the busulfan/fludarabine group was well tolerated compared with that in the modified busulfan/cyclophosphamide group, without an increase in relapse rate.

CONCLUSIONS

Our results demonstrated that myeloablative busulfan/fludarabine might be a highly effective and low-toxicity alternative for patients with acute myeloid leukemia.

Efficacy of Cidofovir in Treatment of BK Virus-Induced Hemorrhagic Cystitis in Allogeneic Hematopoietic Cell Transplant Recipients

BK virus-associated hemorrhagic cystitis (BK-HC) is a common complication after allogeneic hematopoietic stem cell transplantation (allo-HCT), with incidences up to 70%. Cidofovir is an antiviral agent with growing evidence as a therapeutic intervention. To assess the safety profile and efficacy of intravenous and intravesical cidofovir in allo-HCT patients with BK-HC, a retrospective study was undertaken of the allo-HCT cohort who received cidofovir for symptomatic BK-HC (hematuria with BK viruria or viremia) from January 2010 until March 2017 in a single transplant center in Ontario, Canada. The primary outcome measure was a reduction in BK-HC severity (graded from 1 to 4); secondary outcomes included overall survival, BK virus titers, and the onset of acute kidney injury. Twelve allo-HCT patients received cidofovir for BK-HC, with pretreatment clinical severity of 3 (50%) or 4 (50%). Cidofovir was administered via intravenous (33%), intravesical (58%), or both modalities (8%). After a median cumulative dose of 10 mg/kg (range, 1 to 37), mean BK-HC grade decreased significantly by 1.8 (3.5 precidofovir, 1.7 postcidofovir, P < .01). Sixty-six percent of patients had at least partial response to cidofovir, with similar response rates between intravenous (66%) and intravesical (62%) administration. Sixty-seven percent of patients died, and 33% of patients experienced renal toxicity, including 2 patients receiving intravesical therapy. In this retrospective series, there was a significant reduction in BK-HC severity after cidofovir administration; most patients achieved at least partial response after cidofovir administration. Even with intravesical instillation, acute kidney injury remains a potential complication of cidofovir. Although cidofovir may be an efficacious therapy for BK-HC, albeit with potential demonstrated toxicities, further prospective trials are needed.

Treatment of late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation: the role of corticosteroids

We aimed to evaluate the treatments, particularly the role of corticosteroids, in patients with late-onset hemorrhagic cystitis (LOHC) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). One hundred and sixty-three consecutive patients who underwent non-T-cell-depleted allo-HSCT and met the criterion of LOHC after allo-HSCT were enrolled in this study. The median time from allo-HSCT to the occurrence of LOHC was 29 (range, 4–155) days. Pathogens identified in blood and/or urine samples from 143 patients were mostly viruses. All of the patients with LOHC received intravenous fluid hydration, alkalization, and forced diuresis, of which 2 patients achieved complete remission (CR) after these treatments. The remaining 161 patients received anti-infection therapies and 71 achieved CR after the therapies. Corticosteroids were additionally applied to 83 out of 90 patients who did not achieve CR after anti-infection therapies, and 88.0% (n = 73) of them showed a grade 3 to 4 LOHC at the beginning of corticosteroid therapy. Thirty-five patients showed an immediate response (CR or downgraded at least one grade) within 1 week after the beginning of the corticosteroid therapy. Sixty-four patients (77.1%) achieved CR after corticosteroid therapy, and the median period from the beginning of corticosteroid therapy to CR was 17 days. Thus, we observed that viruses were the most common pathogens in LOHC after allo-HSCT and that anti-infection therapies were critical. For patients not showing a satisfactory response to anti-infection therapies, additional corticosteroid therapy may help to achieve CR.

Inhibition of Retrograde Transport Limits Polyomavirus Infection In Vivo

PyVs can cause significant morbidity and mortality in immunocompromised individuals. No clinically efficacious anti-PyV therapeutic agents are available. A recently identified inhibitor of retrograde transport, Retro-2^cycl, blocks movement of PyV virion-containing vesicles from early endosomes to the endoplasmic reticulum, an early step in the PyV life cycle. Retro-2^cycl and its derivatives have been shown to inhibit infection by human PyVs in tissue culture. Here, we demonstrate that a derivative of Retro-2^cycl, Retro-2.1, reduces infection by MuPyV in the kidneys of acutely infected mice. Mimicking the common clinical scenario of PyV resurgence, we further show that MuPyV levels increase in the kidneys of immunocompromised, persistently infected mice and that this increase is inhibited by Retro-2.1. These data provide the first evidence for control of a natural PyV infection in vivo by administration of an inhibitor of retrograde transport.

Polyomaviruses (PyVs) silently infect most humans, but they can cause life-threatening diseases in immunocompromised individuals. The JC polyomavirus (JCPyV) induces progressive multifocal leukoencephalopathy, a severe demyelinating disease in multiple sclerosis patients receiving immunomodulatory therapy, and BK polyomavirus (BKPyV)-associated nephropathy is a major cause of kidney allograft failure. No effective anti-PyV agents are available. Several compounds have been reported to possess anti-PyV activity in vitro, but none have shown efficacy in clinical trials. Productive PyV infection involves usurping the cellular retrograde vesicular transport pathway to enable endocytosed virions to navigate to the endoplasmic reticulum where virion uncoating begins. Compounds inhibiting this pathway have been shown to reduce infection by simian virus 40 (SV40), JCPyV, and BKPyV in tissue culture. In this study, we investigated the potential of Retro-2.1, a retrograde transport inhibitor, to limit infection by mouse polyomavirus (MuPyV) in vivo. We found that Retro-2.1 significantly reduced MuPyV levels in the kidney during acute infection without affecting renal function or the MuPyV-specific CD8 T cell response. To approximate the clinical setting of PyV resurgence in immunocompromised hosts, we showed that antibody-mediated depletion of T cells in persistently infected mice elevated MuPyV levels in the kidney and that Retro-2.1 blunted this increase in virus levels. In summary, these data indicate that inhibition of retrograde vesicular transport in vivo controls infection in a natural PyV mouse model and supports development of these compounds as potential therapeutic agents for individuals at risk for human PyV-associated diseases.

IMPORTANCE PyVs can cause significant morbidity and mortality in immunocompromised individuals. No clinically efficacious anti-PyV therapeutic agents are available. A recently identified inhibitor of retrograde transport, Retro-2^cycl, blocks movement of PyV virion-containing vesicles from early endosomes to the endoplasmic reticulum, an early step in the PyV life cycle. Retro-2^cycl and its derivatives have been shown to inhibit infection by human PyVs in tissue culture. Here, we demonstrate that a derivative of Retro-2^cycl, Retro-2.1, reduces infection by MuPyV in the kidneys of acutely infected mice. Mimicking the common clinical scenario of PyV resurgence, we further show that MuPyV levels increase in the kidneys of immunocompromised, persistently infected mice and that this increase is inhibited by Retro-2.1. These data provide the first evidence for control of a natural PyV infection in vivo by administration of an inhibitor of retrograde transport.

[Comparison of clinical features of hemorrhagic cystitis after haploidentical and matched sibling donor allogeneic hematopoietic stem cell transplantation]

Objective: To compare incidence and clinical features of hemorrhage cystitis (HC) after haploidentical donor (HID) allogeneic hematopoietic stem cell transplantation (HSCT) and matched sibling donor (MSD) HSCT. Methods: Medical records of 609 (including 406 HID-HSCT and 203 MSD-HSCT cases) hematologic malignancies patients treated with HSCT undergoing myeloablative conditioning regimen from January 2011 to December 2012 were analyzed retrospectively. Results: HC occurred 183 in HID and 17 ones in MSD respectively. The cumulative incidence of HC in HID group was higher than in MSD group[ (45.6±2.5) % vs (8.5±2.0) %, χ(2)=77.331, P<0.001], and the cumulative incidence of severe HC (grade 3-4) in HID cases was also higher than in MSD ones[ (11.2±1.9) % vs (2.1±1.1) %, χ(2)=12.883, P<0.001]. All HCs were occurred within 180 days in both groups. The median time to onset in two groups were 27 days after HSCT (range 0-177 days) and 29 days after HSCT (range 6-72 days) respectively (P=0.766) . The median duration of HC in two groups were 21 days (range 3-157 days) and 13 days (range 5-67 days) , respectively (P=0.182) . The total efficiency of treatment in two groups were 69.9% and 70.6% respectively (χ(2)=0.003, P=1.000) . Conclusion: The cumulative incidences of HC and severe HC were higher in HID cases than in MSD ones. The median time to onset and median duration of HC and therapeutic outcome between HID and MSD were comparable.

Are the Polyomaviruses BK and JC Associated with Opportunistic Infections, Graft-versus-Host Disease, or Worse Outcomes in Adult Patients Receiving Their First Allogeneic Stem Cell Transplantation with Low-Dose Alemtuzumab?

BACKGROUND

The association of polyomaviruses BK and JC with other opportunistic infections and graft-versus-host disease (GvHD) in allogeneic stem cell transplantation is controversially discussed.

METHODS

We conducted a retrospective study of 64 adult patients who received their first allogeneic stem cell transplantation between March 2010 and December 2014; the follow-up time was 2 years.

RESULTS

Acute leukemia was the most frequent underlying disease (45.3%), and conditioning included myeloablative (67.2%) and nonmyeloablative protocols (32.8%). All patients received 10 mg of alemtuzumab on day -2 (20 mg in case of mismatch) as GvHD prophylaxis. Twenty-seven patients (41.5%) developed cytomegalovirus (CMV) reactivation. BKPyV-associated hemorrhagic cystitis was diagnosed in 10 patients (15.6%). Other opportunistic infections caused by viruses or protozoa occurred rarely (<10%). There was no association of BKPyV or JCPyV with CMV reactivation, Epstein-Barr virus reactivation, human herpes virus 6, or parvovirus B19 infection requiring treatment. There was a significant correlation of BKPyV-associated hemorrhagic cystitis with toxoplasmosis (p = 0.013). Additionally, there was a significant link of simultaneous BKPyV and JCPyV viruria with toxoplasmosis (p = 0.047). BKPyV and JCPyV were not associated with GvHD, relapse, or death.

CONCLUSION

We found no association of BKPyV or JCPyV with viral infections or GvHD. Only the correlation of both polyomaviruses with toxoplasmosis was significant. This is a novel and interesting finding.

BK Polyomavirus and the Transplanted Kidney: Immunopathology and Therapeutic Approaches

BK polyomavirus is ubiquitous, with a seropositivity rate of over 75% in the adult population. Primary infection is thought to occur in the respiratory tract, but asymptomatic BK virus latency is established in the urothelium. In immunocompromised host, the virus can reactivate but rarely compromises kidney function except in renal grafts, where it causes a tubulointerstitial inflammatory response similar to acute rejection. Restoring host immunity against the virus is the cornerstone of treatment. This review covers the virus-intrinsic features, the posttransplant microenvironment as well as the host immune factors that underlie the pathophysiology of polyomavirus-associated nephropathy. Current and promising therapeutic approaches to treat or prevent this complication are discussed in relation to the complex immunopathology of this condition.

Incidence, risk factors and the effect of polyomavirus infection in hematopoietic stem cell transplant recipients

Objective The effect of polyomavirus infection in HSCT recipients is poorly understood. Methods We evaluated 38 HSCT recipients. Polyomavirus was detected by nested qualitative polymerase chain reaction (PCR) assays of urine. The risk factors for BK virus and JC virus were analysed. The kidney and liver functions of infected and uninfected patients were compared. Results BK virus, JC virus, and simian virus 40 were detected in 21%, 42%, and 0% of HSCT recipients respectively. HCMV infection was found to be an independent risk factor for JC virus infection (odds ratio (OR): 8.528), while transplants with mismatched HLA are more susceptible to BK virus infection (OR: 12.000). Liver function of JC virus-infected subjects was worse than that of uninfected subjects. Conclusion We must be vigilant for opportunistic polyomavirus infections in HSCT recipients, especially those with HCMV co-infection or a mismatched HLA transplant. When unexplained liver function deterioration is observed, JC virus infection should be considered.

Nationwide survey of BK polyomavirus associated hemorrhagic cystitis in adult allogeneic stem cell transplantation among haematologists and urologists

There are no epidemiological data on BK virus associated hemorrhagic cystitis (BKHC) in adult allogeneic stem cell transplantation in Germany available and associations with clinical conditions like GvHD are controversially discussed. Therefore, we conducted a nationwide survey among haematologists and urologists about this disease. We developed two questionnaires, one for haematologists (26 items) and one for urologists (20 items) concerning BKHC in adult allogeneic stem cell transplantation with epidemiological data and clinical implications. The survey was sent out at least three times to EBMT registered centres performing at least five transplantations a year, leading to 39 centres. The recruiting time was between January and June 2016. Total response rates were 76.9% among haematologists and 74.4% among urologists. BKHC seems to appear less frequent in this survey than it is described in the literature. Six deaths in the last 5 years due to this disease have been reported. Interestingly, haematologists as well as urologists mostly think that local therapy is most effective while 50.0% stated that there is no real effective oral or intravenous medication. Associations with other clinical conditions mentioned were heterogeneous, e.g. transplantation type, CMV reactivation, acute GvHD, nephropathy and worse clinical outcome. There was a significant discrepancy between haematologists and urologist concerning the association with acute GvHD (p = 0.004). We need prospective, multicentric clinical studies to evaluate local therapy and for developing a risk stratification model since this disease can be severe with morbidity and rarely mortality. In our opinion, this should be an interdisciplinary approach.

BK Virus-Associated Hemorrhagic Cystitis After Allogeneic Hematopoietic Stem Cell Transplantation in the Pediatric Population

OBJECTIVE

To study the incidence, risk factors, and treatment of hemorrhagic cystitis secondary to BK-virus reactivation (HC-BKV) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the pediatric population.

METHODS

Case-control study in which all pediatric patients (0-18 years) who underwent allo-HSCT from September 2009 to January 2014 were followed.

RESULTS

Twenty-nine patients underwent an allo-HSCT. The median age was 9 years (range = 6 months to 15 years), 61% male. The primary diagnosis was acute lymphoblastic leukemia (72.4%). Six (20.7%) developed HC-BKV. In a multivariate analysis of risk factors, it was observed that the reactivation of BK virus was associated with age more than 10 years ( P = .098) and those with positive serology for Epstein-Barr virus ( P = .06). Five of the 6 patients with HC-BKV received cidofovir (CDV) at doses of 3 to 5 mg/kg/week. The treatment lasted a median of 3 cycles (range = 2-5). One of the patients (20%) developed nephrotoxicity. Of the 5 patients treated with CDV, 3 (60%) had a complete response, 1 (20%) partial response, and 1 (20%) no response.

CONCLUSION

We conclude that HC-BKV is a frequent complication after allo-HSCT. CDV therapy can be effective but controlled clinical trials are needed.

Urological Complications and BK Virus-Associated Diseases Under Allogenic Stem Cell Transplantation

Every year 50,000 patients receive a stem cell transplantation worldwide, but there is lack of data pertaining to urological complications.

METHODS

We performed a retrospective analysis of all adult patients undergoing their first allogenic stem cell transplantation from January 2011 to June 2013 in our institution. Statistical tests performed were Pearson's correlation, chi-square testing and logistic regression using SPSS 22.0.

RESULTS

We identified 39 patients (22 males, 17 females). Twenty four patients (61.5%) had a urological complication. Most frequent urologic complications were bacterial urinary tract infection (n = 13; 33.3%), acute renal failure (n = 6; 15.4%) and BK virus-associated haemorrhagic cystitis (n = 5; 12.8%). BK viruria was detected in 12 patients (30.8%). We observed an association of creatinine increase (about 20 µmol/l at time of onset of BK viruria) with BK viruria (Pearson's correlation 0.64; p = 0.01), and BK viruria is significantly linked to acute renal failure (Pearson's correlation 0.35; p = 0.029). In univariate regression, BK viruria is significantly linked to urological complication (p = 0.025).

CONCLUSIONS

We suggest that BK virus infection during stem cell transplantation can lead to BK virus associated nephropathy, which is so far only known from patients after kidney transplantation.

Risk Factors Associated with Severity and Outcomes in Pediatric Patients with Hemorrhagic Cystitis

PURPOSE

Hemorrhagic cystitis is a complication of treatment of pediatric cancer with considerable variation in severity and morbidity. This study presents an analysis of hemorrhagic cystitis severity and treatment outcomes in a large pediatric population.

MATERIALS AND METHODS

Patients with hemorrhagic cystitis treated at St. Jude Children's Research Hospital® were identified from 1990 to 2010. Demographic data were gathered along with information pertaining to initial primary diagnosis, hemorrhagic cystitis diagnosis and treatment, and mortality. Statistical analyses were performed to evaluate associations between risk factors and severity of hemorrhagic cystitis as well as treatment outcomes.

RESULTS

Of the 285 patients who met inclusion criteria 54% were male. Mean age was 11.41 years. Mean time from initial primary diagnosis to hemorrhagic cystitis onset was 29 months. Noninvasive treatment was performed in 246 patients (86%) and operative intervention was required in 14 (4.9%). Bivariate analysis demonstrated that pelvic radiation therapy (p = 0.0002), any radiation therapy (p = 0.005), acute lymphocytic leukemia (p = 0.01), bone marrow transplantation (p = 0.0225), cyclophosphamide exposure (p = 0.0419) and BK virus positivity (p = 0.0472) were predictors of higher grade hemorrhagic cystitis. Factors correlating with the need for invasive management on bivariate analysis included pelvic radiation therapy (p = 0.0266), bone marrow transplantation (p = 0.0007), hematological malignancy (p = 0.0066), ifosfamide exposure (p = 0.0441) and male gender (p = 0.0383). Multivariate analysis showed independent effects of pelvic radiation therapy (p = 0.001) and delayed onset of hemorrhagic cystitis (p = 0.0444).

CONCLUSIONS

Severity of hemorrhagic cystitis and failure of noninvasive management correlate with several identifiable risk factors. Prospective identification of patients with these risk factors may allow for targeted early intervention in those at highest risk.

Reactivation of polyomavirus in the genitourinary tract is significantly associated with severe GvHD and oral mucositis following allogeneic stem cell transplantation

PURPOSE

BK-virus and JC-virus are the most common polyomaviridae associated with hemorrhagic cystitis in the allogeneic transplant setting. Hemorrhagic cystitis and symptomatic viruria caused by these viruses are a major cause of morbidity in patients undergoing allogeneic stem cell transplantation.

METHODS

We performed a retrospective evaluation on a highly uniform study population of 73 patients receiving allogeneic stem cell transplantation. Patients were treated according to the FLAMSA-RIC-protocol, and were examined for the incidence of BK-/JC-viruria and late-onset BK-positive hemorrhagic cystitis within a two-year period.

RESULTS

The occurrence of BK-viruria was correlated with published risk factors (acute GvHD, oral mucositis, donor type, conditioning, age, gender). Thirty patients (41 %) were found to excrete either BK-virus (n = 17), JC-virus (n = 3) or both (n = 10), of whom 18 patients (60 %) developed higher-grade hemorrhagic cystitis as opposed to none in the virus-negative control group. Higher grade GvHD (grade B-D) was more common in patients with viruria (p = 0.013) and also more common in patients with manifest hemorrhagic cystitis (p = 0.048). Similarly, oral mucositis was associated both with viruria (p = 0.014) and hemorrhagic cystitis (p = 0.005). Manifest cystitis but not viruria was significantly associated with male gender (p = 0.016). No significant correlation was found with age, conditioning with busulfane vs total body irradiation or related vs unrelated donor.

CONCLUSIONS

Severe GvHD and oral mucositis are significantly associated with reactivation of polyomaviridae in the genitourinary-tract already at the level of asymptomatic viruria.

Pharmacokinetics and safety of intravesicular cidofovir in allogeneic HSCT recipients

OBJECTIVES

The objective of this study was to evaluate the pharmacokinetics and safety of cidofovir administered via the intravesicular route to patients with haemorrhagic cystitis following allogeneic HSCT (allo-HSCT).

METHODS

Patients with gross haematuria and confirmed BK or adenovirus viruria following allo-HSCT were prospectively enrolled in an open-label pharmacokinetic study (ClinicalTrials.gov registration: NCT01816646). Three hours after an oral probenecid dose (2 g), cidofovir (2.5-5 mg/kg in 50-100 mL of normal saline) was given via a transurethral catheter for up to 2 h of dwell time. Serial plasma samples were obtained over 24 h and assayed for cidofovir concentrations using LC-MS/MS. A custom pharmacokinetic model with a time-limited absorption compartment was fitted to the concentration-time profile of each patient. Systemic drug exposure was expressed as AUC0-24, by integrating the best-fit profile with respect to time.

RESULTS

Six subjects (mean ± SD age = 38 ± 21 years) with baseline serum creatinine <1.4 mg/dL were enrolled. Mean values for volume of distribution, clearance and elimination half-life were 19.5 L, 5.6 L/h and 2.8 h, respectively. Compared with the reported AUC0-24 for an equivalent intravenous dose, intravesicular instillation of cidofovir resulted in 1%-74% of the corresponding systemic exposure. Owing to primarily lower abdominal pain, only two patients were able to tolerate a 2 h dwell time. One patient developed a >50% increase in serum creatinine within 7 days of administration.

CONCLUSIONS

Intravesicular administration of cidofovir resulted in highly variable systemic exposures. The safety and efficacy of intravesicular cidofovir should be further evaluated before routine use.

Incidence and risk factors for hemorrhagic cystitis in unmanipulated haploidentical transplant recipients

BACKGROUND

Hemorrhagic cystitis (HC) is a common complication after hematopoietic allogeneic stem cell transplantation (HSCT) associated with intensity of the conditioning regimen, cyclophosphamide (Cy) therapy, and BK polyomavirus (BKPyV) infection.

METHODS

We analyzed 33 consecutive haploidentical (haplo) HSCT recipients transplanted for hematologic diseases. Eleven patients had a previous transplant. Median follow-up was 11 months. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine + mycophenolate mofetil and post-HSCT Cy.

RESULTS

Thirty-two of 33 patients achieved neutrophil recovery. Cumulative incidence (CI) of platelet recovery was 65%. CI grade II-IV acute GVHD was 44%. Twenty patients developed HC in a median time of 38 days. CI of HC at day 180 was 62%. BKPyV was positive in blood and urine of 91% of patients at HC onset. HC resolved in 18/20 patients. Factors associated with HC were previous transplant (P = 0.01) and occurrence of cytomegalovirus reactivation before HC (P = 0.05). Grade II-IV acute GVHD was not associated with HC (P = 0.62). CI of day 180 viral infections was 73%. Two-year overall survival (OS) was 50%; HC did not impact OS (P = 0.29).

CONCLUSION

The incidence of HC after haplo with post-HSCT Cy is high and is associated with morbidity, especially in high-risk patients such as those with a previous transplant history and with impaired immune reconstitution.

Hemorrhagic cystitis after allogeneic hematopoietic cell transplantation: risk factors, graft source and survival

Although hemorrhagic cystitis (HC) is a common complication of allogeneic hematopoietic cell transplantation (alloHCT), its risk factors and effects on survival are not well known. We evaluated HC in a large cohort (n=1321, 2003-2012) receiving alloHCT from all graft sources, including umbilical cord blood (UCB). We compared HC patients with non-HC (control) patients and examined clinical variables at HC onset and resolution. Of these 1321 patients, 219 (16.6%) developed HC at a median of 22 days after alloHCT. BK viruria was detected in 90% of 109 tested HC patients. Median duration of HC was 27 days. At the time of HC diagnosis, acute GVHD, fever, severe thrombocytopenia and steroid use were more frequent than at the time of HC resolution. In univariate analysis, male sex, age <20 years, myeloablative conditioning with cyclophosphamide and acute GVHD were associated with HC. In multivariate analysis, HC was significantly more common in males and HLA-mismatched UCB graft recipients. Severe grade HC (grade III-IV) was associated with increased treatment-related mortality but not with overall survival at 1 year. HC remains hazardous and therefore better prophylaxis, and early interventions to limit its severity are still needed.

Polyomaviruses and disease: is there more to know than viremia and viruria?

Purpose of review

Polyomavirus nephropathy (PVN) mainly caused by BK virus (BKV) remains the most common productive viral infection of the kidney. Over the past decade, clinical interest often focused on BK viremia and viruria as the diagnostic mainstays of patient management. The purpose of this review is to discuss viral nephropathy in the context of BK viremia and viruria and new strategies to optimize diagnostic accuracy and patient management. The emerging roles of polyomaviruses in oncogenesis, salivary gland disease, and post-bone marrow transplantation as well as novel Polyomavirus strains are highlighted.

Recent findings

Areas of investigation include proposals by the Banff working group on the classification of PVN and studies on PVN progression and resolution, including the role cellular immune responses may play during reconstitution injury. New noninvasive strategies to optimize the diagnosis of PVN, that is, the urinary ‘polyomavirus-haufen’ test and mRNA expression levels for BKV in the urine, hold great promise to accurately identify patients with viral nephropathy. Tools are now available to separate ‘presumptive’ from ‘definitive’ disease in various patient cohorts including individuals post-bone marrow transplantation. Recent observations also point to a currently underrecognized role of polyomaviruses in oncogenesis post-transplantation and salivary gland disease in patients with HIV-AIDS.

Summary

This review summarizes recent studies on PVN and the significance of the BKV strain in disease. Current paradigms for patient management post-(renal) transplantation are discussed in the setting of new observations. Issues that still require clarification and further validation are highlighted.