Clinical effectiveness of hyperbaric oxygen therapy for BK-virus-associated hemorrhagic cystitis after allogeneic bone marrow transplantation

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.

An expert consensus on prevention, diagnosis, and management of hemorrhagic cystitis in pediatric hematopoietic cell transplantation, on behalf of the Infectious Disease and Hematopoietic Cell Transplant Working groups of Italian Pediatric Hematology Oncology Association (AIEOP)

The optimal management of hemorrhagic cystitis (HC) in hematopoietic stem cell transplantation (HCT) is debated, both for early onset HC (EOHC) secondary to chemotherapy toxicity and BK Polyomavirus (BKPyV)-related HC, due to the lack of controlled trials, particularly referred to pediatric setting. Actually, clinical practice is mainly based on guidelines of the European Conference on Infections in Leukemia, 6th edition, which considers both adult and pediatric populations but concludes that, despite much progress in understanding the pathogenesis, epidemiology, and risk factors, this complication still represents a disabling unmet clinical need with limited prophylactic and therapeutic options. Additionally, the Guidelines of the American Society of Clinical Oncology define the management of chemotherapeutic toxicity independently from the patients' population. A panel of experts belonging to the Hematopoietic Cell Transplant and Infectious Disease Working Group (WG) of Associazione Italiana di Emato-Oncologia Pediatrica (AIEOP) developed a consensus to define the best practices in prevention, diagnosis, and management of HC in pediatric HCT setting.

BK virus-associated hemorrhagic cystitis in pediatric stem cell transplantation: a case report and scoping review

Introduction

BK virus-associated hemorrhagic cystitis (BK-HC) is a debilitating and poorly understood complication of hematopoietic stem cell transplantation (SCT). Hematuria, dysuria, and other symptoms associated with BK-HC are common in the immediate post-SCT period, making BK-HC difficult to distinguish from other conditions presenting with these symptoms. Despite published criteria for diagnosis, the degree to which these criteria are consistently applied to either clinical diagnosis or to studies informing BK-HC management is unclear. We present a case of BK-HC in a pediatric SCT recipient, and discuss the challenges associated with treatment in the absence of rigorous data to inform clinical management.

Methods

We reviewed all cases of BK viruria at our center in patients undergoing SCT between January 2015 and December 2019. We then performed a scoping review of publications in PubMed addressing BK-HC, specifically focusing on how BK-HC was defined. Publications using the keywords "BK polyomavirus" and "hemorrhagic cystitis" were included if they involved a clinical study of SCT recipients and a full-text article was available in English. Case reports were excluded. Analysis focused on whether BK-HC was explicitly defined and whether the definition incorporated elements of diagnostic criteria published by European Conference on Infections in Leukemia (ECIL).

Results

A total of 30 studies published between January 2018 and 30 June 2021 met criteria for review, including 4 clinical trials, 7 prospective observational studies, and 19 retrospective observational studies. Fifteen of these studies included pediatric patients (7 pediatric only, 8 combined adult and pediatric). Of the 30 publications, 19 included a definition of either BK-HC or BK cystitis, with only five using ECIL criteria, all of which were observational studies. Multiple interventions are described for treatment of BK-HC, including cidofovir, leflunomide, quinolones, hyperbaric oxygen, keratinocyte growth factor, and BK-specific cytotoxic T lymphocytes. However, evidence to support efficacy for any of these interventions is lacking.

Discussion

Although BK-HC is a well-known complication of SCT, evidence to support available treatment options is limited. Well-controlled studies that incorporate clear diagnostic criteria are needed to better define the risk factors, natural history, and ideal interventions.

Risk factors for BK virus-associated hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation: A systematic review and meta-analysis

OBJECTIVE AND BACKGROUND

BK virus-associated hemorrhagic cystitis (BKV-HC) is an intractable complication leading to higher mortality and prolonged hospitalization among allogeneic hematopoietic stem cell transplantation (allo-HCT) recipients. Therefore, identifying the potential risk factors of BKV-HC after allo-HCT is crucial to improve prognosis and for early prevention. However, the risk factors for BKV-HC remain debatable. Therefore, we conducted a systematic review and meta-analysis to identify the risk factors for BKV-HC, for early prevention of the occurrence of BKV-HC and to improve the quality of life and prognosis of allo-HCT recipients.

METHODS

We searched relevant studies from PubMed, EMBASE, and the Cochrane Library up to February 2023. The odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) of all risk factors were calculated to evaluate their effects on the occurrence of BKV-HC.

RESULTS

Overall, 11 studies involving 2556 allo-HCT recipients were included in this meta-analysis. All included studies were retrospective and published between 2013 and 2022. We found that male sex (OR = 1.32; 95% CI, 1.07-1.62; p = .009, I2  = 34%), haploidentical donor (OR = 1.84; 95% CI, 1.18-2.87; p = .007, I2  = 23%), myeloablative conditioning (OR = 1.76; 95% CI, 1.36-2.28; p < .0001, I2  = 45%), acute graft versus host disease (aGVHD) (OR = 2.73; 95% CI, 2.02-3.69; p < .0001, I2  = 46%), chronic graft versus host disease (cGVHD) (OR = 1.71; 95% CI, 1.12-2.60; p = .01, I2  = 0%), and cytomegalovirus (CMV) reactivation (OR = 3.13; 95% CI, 1.12-8.78; p = .03, I2  = 79%) were significantly associated with BKV-HC in the univariable analysis.

CONCLUSIONS

Our meta-analysis indicated that male sex, haploidentical donor, myeloablative conditioning, aGVHD, cGVHD, and CMV reactivation were potential risk factors for BKV-HC.

[Haemorrhagic cystitis following hematopoietic stem cell transplantation: Prophylaxis, diagnosis, and treatment. Guidelines from the SFGM-TC]

Hemorrhagic cystitis (HC) is a common complication after allogeneic hematopoietic cell transplantation (allo-HCT). Its manifestations range from microscopic hematuria without urinary symptoms to extensive and prolonged macroscopic hemorrhage requiring invasive interventions that can often prolong the duration of hospitalization and result in significant morbidity. The early onset of HC is related to allo-HCT conditioning regimen, whereas the late onset form is secondary to viral infection, most commonly due to BK virus. In the framework of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) practice harmonization workshops held in Lille in September 2021, the prophylaxis, the diagnostic approach and the treatments of HC following allografting were reviewed after analysis of published studies.

Effectiveness of hyperbaric oxygen therapy for virus-associated hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation

Although some studies have suggested the effectiveness of hyperbaric oxygen (HBO) therapy for hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation (HSCT), the role of HBO has not been established. We compared the treatment outcomes of 8 patients with viral HC (adenovirus [ADV], n = 2; BK virus [BKV], n = 6) treated with HBO (HBO[+]) and 8 patients (ADV, n = 2; BKV, n = 6) treated with conventional therapy (HBO[−]), such as urinary catheterization and intravenous cidofovir. HBO therapy was performed at 2.1 atmospheres for 90 min/day until clinical improvement was achieved. The median number of HBO treatments was 10 (range 8–12). The median duration of HBO treatment was 19.5 days (range 10–23 days). All 8 HBO(+) patients achieved complete remission (CR) at a median of 14.5 days (range 5–25 days). Of the 8 HBO(−) patients, 5 (62.5%) obtained CR and 3 remained symptomatic for 2–6 months. The cumulative incidence of transplant-related mortality at day 100 after allogeneic HSCT was significantly higher in the HBO(−) patients than in the HBO(+) patients (14.2 vs. 0%, P < 0.05). No severe HBO-related adverse effects were observed. In conclusion, HBO is a feasible option for treating viral HC after allogeneic HSCT.

Management of BK virus-associated haemorrhagic cystitis in allogeneic stem cell transplant recipients

BK virus (BKV)-related haemorrhagic cystitis (HC) is an important cause of morbidity following allogeneic haematopoietic stem cell transplantation (HSCT). The various risk factors include high-level BKV viruria and/or viremia, myeloablative conditioning, acute graft versus host disease (GVHD), cytomegalovirus viremia, and unrelated or HLA-mismatched donor. The presence of high plasma BK viral load and cytopenias have been implicated as important predictors for protracted disease course. These patients frequently require hospitalisation which may extend for several weeks. Supportive measures in the form of analgesics, intravenous hydration, bladder irrigation, and transfusion support remain the mainstay of management. Various drugs have been used with limited success in this setting. These include antiviral drugs, fluoroquinolones, leflunomide, growth factors, clotting factors, estrogens, and prostaglandins. The role of adoptive cellular immunotherapy has also been explored but lacks clinical validation. The strategies aimed at expediting urothelial repair like hyperbaric oxygen therapy (HBOT), intravesical fibrin glue and platelet-rich plasma (PRP) are emerging. Some patients with severe disease do require surgical intervention to relieve urinary obstruction. The frequent co-occurrence of acute GVHD and CMV disease further complicates the management in such patients. There is an unmet need for effective and evidence-based options for the prevention and management of this disease. Due to lack of robust data supported by randomised trials, the acceptability of the available guidelines to simplify the treatment is expected to be low. Despite the availability of various treatment options, the management of BKV-related HC in day-to-day practice continues to be a challenge. The aim of this article is to put forward an up-to-date review of the preventive and therapeutic strategies for BKV-related HC.

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.

Hyperbaric Oxygen Therapy of an Adolescent Stem Cell Transplantation Recipient with Hemorrhagic Cystitis and BK Virus

Hyperbaric oxygen therapy (HBOT) continues to show effectiveness in the treatment of several diseases and benefits such as fibroblast proliferation, capillary angiogenesis, and decreasing edema, especially in hemorrhagic cystitis (HC). We report a case of a 15-year-old male with chronic myelogenous leukemia status posthaploidentical stem cell transport with BK virus in the United States to be treated by HBOT. The patient received a total of 30 HBOT treatments for 90 minutes at 2 ATA. After HBOT treatments, patient showed signs of improvements such as cessation of hemorrhage cystitis. The findings of this case support and shows that there is growing evidence for the use of HBOT as adjunctive therapy for patients with BK virus associated with HC after stem cell transplantation.

The Role of Hyperbaric Oxygen Treatment for COVID-19: A Review

The recent coronavirus disease 2019 (COVID-19) pandemic produced high and excessive demands for hospitalizations and equipment with depletion of critical care resources. The results of these extreme therapeutic efforts have been sobering. Further, we are months away from a robust vaccination effort, and current therapies provide limited clinical relief. Therefore, several empirical oxygenation support initiatives have been initiated with intermittent hyperbaric oxygen (HBO) therapy to overcome the unrelenting and progressive hypoxemia during maximum ventilator support in intubated patients, despite high FiO2. Overall, few patients have been successfully treated in different locations across the globe. More recently, less severe patients at the edge of impending hypoxemia were exposed to HBO preventing intubation and obtaining the rapid resolution of symptoms. The few case descriptions indicate large variability in protocols and exposure frequency. This summary illustrates the biological mechanisms of action of increased O₂ pressure, hoping to clarify more appropriate protocols and more useful application of HBO in COVID-19 treatment.

Infections with DNA Viruses, Adenovirus, Polyomaviruses, and Parvovirus B19 in Hematopoietic Stem Cell Transplant Recipients and Patients with Hematologic Malignancies

Infections due to adenovirus, polyomaviruses (BK and JC viruses), and parvovirus B19 may not be as common as infections due to other DNA viruses, such as cytomegalovirus in patients with hematological malignancies and the recipients of hematopoietic stem cell transplantation. However, these infections may result in life-threatening diseases that significantly impact patients' recovery, morbidity, and mortality. Treating physicians should be aware of the diseases associated with these viruses, the patient populations at increased risk for complications due to these infections, and the available diagnostic and therapeutic approaches.

BK Virus Associated Haemorrhagic Cystitis. A systematic review of current prevention and treatment strategies

BACKGROUND

BK virus is a major cause of late onset haemorrhagic cystitis in patients undergoing Haematopoietic Cell Transplantation (HCT). The evidence for the management of BK Virus Associated Haemorrhagic Cystitis (BKV-HC) is limited. Much of the published data consists of non-randomised case series and case reports. To our knowledge this is the first systematic review for the management of BKV-HC in both paediatric and adult populations. Our primary outcome was to examine the evidence for strategies of 1) prevention and 2) cessation of haematuria associated with BKV. Secondary outcomes were to assess the toxicity of treatment strategies and devise management recommendations for clinicians.

MATERIALS AND METHODS

We performed a systematic review of the PubMed and Central databases to evaluate the current evidence. A search protocol was prepared and registered with the PROSPERO database (CRD42017082442). The review was conducted in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement and AMSTAR (Assessing the methodological quality of systematic reviews) guidelines. Results were classified by treatment type. Qualitative analysis of included articles was performed, and grades of recommendations were devised for each treatment.

RESULTS

Of 896 titles screened, 44 articles were included for qualitative analysis. The overall quality of evidence was low. There is insufficient evidence to recommend prophylactic quinolones. 40 studies evaluated treatments for established BKV-HC. There are no high-quality comparative studies. Cidofovir is the most studied treatment but quality of evidence is low, and grade of recommendation is weak. Hyperbaric oxygen therapy, Fibrin glue, Leflunomide, Sodium Pentosan Polysulfate, Intravesical Alum and Radiological embolisation have all been described but the effectiveness of these treatments is unclear.

CONCLUSION

There remains no clear specific treatment for BKV-HC. An effective multi-disciplinary approach leading to early recognition and initiation of treatment is encouraged. The development of novel therapies followed by well-designed clinical studies are urgently needed.

ECIL guidelines for the prevention, diagnosis and treatment of BK polyomavirus-associated haemorrhagic cystitis in haematopoietic stem cell transplant recipients

Objectives

To define guidelines for BK polyomavirus (BKPyV)-associated haemorrhagic cystitis (BKPyV-HC) after paediatric and adult HSCT.

Methods

Review of English literature and evidence-based recommendations by expert consensus.

Results

BKPyV-HC occurs in 8%-25% of paediatric and 7%-54% of adult recipients undergoing allogeneic HSCT. Diagnosis requires the triad of cystitis, macro-haematuria and high urine BKPyV loads >7 log10 copies/mL, and exclusion of other relevant aetiologies. BKPyV viraemia is frequent and may serve as a more specific semiquantitative follow-up marker. No randomized controlled trials are available to inform antiviral prophylaxis or treatment. However, hyper-hydration and/or bladder irrigation showed limited prophylactic value. Fluoroquinolones are not effective for prophylaxis or treatment, but rather increase antibiotic resistance. Hyperbaric oxygen or fibrin glue is marginally effective based on small case series from correspondingly equipped centres. Although cidofovir has been reported to improve and/or reduce BKPyV viraemia or viruria, the current data do not support its regular use.

Conclusions

BKPyV-HC remains a disabling unmet clinical need in HSCT that requires novel approaches supported by proper clinical trials.

Kidney dysfunction after hematopoietic cell transplantation-Etiology, management, and perspectives

Kidney dysfunction is a common complication of hematopoietic cell transplantation (HCT) with proven negative impact on early and long-term mortality. Causes of this complication are diverse, usually overlapping, and poorly understood. Therefore, management implicates multidirectional investigations and simultaneous treatment of suspected causes. The etiology is frequently unconfirmed due to a lack of specific markers and prevalence of contraindications to renal biopsy among HCT recipients. Herein, we provide a summary of etiology and propose an algorithm for evaluation of kidney injury after HCT. We also map out the most urgent areas for research that aim to identify patients at risk of severe renal injury and develop nephroprotective strategies.

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.

Hyperbaric oxygen as a treatment modality in cyclophosphamide-induced hemorrhagic cystitis

Late-onset HC is a well-recognized complication associated with cyclophosphamide/acrolein-induced toxicity. It poses a management challenge when hyperhydration and bladder irrigation do not result in clinical improvement as desired. The data regarding use of hyperbaric oxygen therapy (HBO2) as an early treatment modality in this clinical setting are limited. We present 2 cases, that were refractory to hyperhydration and bladder irrigation but responded to HBO2. They were treated with 20-30 daily sessions over weekdays with 100% oxygen for 90 minutes at 2 atmospheric pressure units (2 atm). Both patients reported improved symptoms within the first 15 sessions, and hematuria diminished by 20 sessions. Hyperbaric oxygen is a less invasive, outpatient therapy that is effective for treatment of HC and is tolerated well by young patients.

Acute myeloid leukemia and the infectious diseases consultant

Infectious complications following treatment of acute myeloid leukemia (AML) are important causes of morbidity and mortality. The spectrum and complexity of these infections is reflected by the severe net state of immunosuppression of AML patients, that is dynamic and continuously changing, the polypharmacy, including the widespread use of anti-infectives and the complex epidemiology of severe and frequently resistant pathogens afflicting these patients. Infectious diseases (ID) consultants having a critical mass of expertise and intimate knowledge of the intricacies of leukemia care, add considerable value in improving outcomes of patients with AML who develop infections. Furthermore, pharmaco-economic considerations such as length of stay, choice of cost-effective anti-infective program, infection control and antibiotic stewardship strategies create a delicate interplay of the ID consultant and the ecosystem of care of AML patients. This is an increasingly recognized area of cross collaboration and a productive direction for future collaborative practice models and research.

BK nephropathy in the native kidneys of patients with organ transplants: Clinical spectrum of BK infection

Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy (BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.

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.

The apoptosis of peripheral blood lymphocytes promoted by hyperbaric oxygen treatment contributes to attenuate the severity of early stage acute pancreatitis in rats

The aim of this study was to investigate the immunoregulatory effects of hyperbaric oxygen (HBO) via promoting the apoptosis of peripheral blood lymphocytes (PBLs) to attenuate the severity of early stage acute pancreatitis (AP) in rats. Additionally, the persistence of the HBO treatment effects was evaluated. One hundred and twenty male Wistar rats were randomized into four groups: sham, AP, AP + normobaric oxygen (NBO), and AP + HBO. Each group consisted of 30 rats. Four hours after the induction of AP, the 30 rats in the AP + NBO group were given normobaric oxygen treatment with 100 % oxygen at 1 atm for 90 min. The 30 rats in the AP + HBO group received 100 % oxygen at 2.5 atm for 90 min, with a compression/decompression time of 15 min. The 30 rats in the AP group remained untreated. At 6, 12, and 24 h after the induction of AP, surviving rats from each group were sacrificed, and the blood and tissue samples were collected for the following measurements: the partial pressure of oxygen (PaO2) and oxygen saturation (SaO2) of the arterial blood, the levels of serum amylase, lipase, interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-10 (IL-10), hepatocyte growth factor (HGF), and reactive oxygen species (ROS), and the mitochondrial membrane potential (∆Ψm) of the PBLs. The expression levels of procaspase-3, caspase-3, procaspase-9, and caspase-9 were also evaluated in the PBLs. Additionally, the apoptosis of PBLs was assessed, and the pancreatic tissues were subjected to a histopathological analysis by pathological grading and scoring. The histopathology of the lung, liver, kidney, duodenum, and heart was also analyzed at 12 h after the induction of AP. Significant differences were found at 6 and 12 h after AP induction. The HBO treatment significantly elevated the PaO2 and SaO2 levels, and the ROS levels in the PBLs. Additionally, HBO downregulated the levels of amylase and lipase. The HBO treatment also reduced the ∆Ψm levels, upregulated the expression of caspase-3 and caspase-9, and increased the apoptosis rate of the PBLs. Moreover, the HBO treatment decreased the serum concentrations of IL-2, IFN-γ and HGF, and reduced the pathological scores of the pancreatic tissue. The histopathological changes of the lung, liver, kidney, duodenum, and heart were also improved. A significant elevation of IL-10 occurred only at the 12-h time point. However, no obvious differences were found at the 24-h time point. This study demonstrated that the HBO treatment can promote the apoptosis of PBLs via a mitochondrial-dependent pathway and inhibit the inflammatory response. These immunoregulatory effects may play an important therapeutic role in attenuating the severity of early stage AP. The repeated administration of HBO or the use of HBO in combination with other approaches may further improve outcomes.

Mesenchymal stromal cells as an adjuvant treatment for severe late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation

The management of severe late-onset hemorrhagic cystitis (LO-HC) after allogeneic hematopoietic stem cell transplantation (HSCT) is still challenging. Because mesenchymal stromal cells (MSCs) possess anti-inflammatory and tissue repair-promoting properties, we retrospectively analyzed the efficacy and safety of MSC infusions in 7 of 33 patients with severe LO-HC after allogeneic HSCT. During treatment, each patient received at least one MSC infusion of Wharton's jelly derived from the umbilical cord of a third-party donor. In 6 patients, MSC treatment was initiated within 3 days of gross hematuria onset, while the 7th patient received an infusion 40 days later. The median dose was 1.0 (0.8-1.6) × 10(6)/kg. Five of 7 patients responded to treatment. Notably, gross hematuria promptly disappeared in 3 patients after 1 infusion, with a time to remission not seen in patients without MSC infusion. Two patients showed no response even after several infusions. No acute or late complications were recorded. Our findings indicate that MSC transfusion might be a feasible and safe supplemental therapy for patients with severe LO-HC after allogeneic HSCT.

Successful hyperbaric oxygen therapy for refractory BK virus-associated hemorrhagic cystitis after cord blood transplantation

BK virus-associated hemorrhagic cystitis (BKV-HC) is a common and major cause of morbidity in recipients of allogeneic hematopoietic stem cell transplantation. A 32-year-old woman developed severe BKV-HC on day 24 after cord blood transplantation (CBT). Despite supportive therapies - such as hyperhydration, forced diuresis, and urinary catheterization - macroscopic hematuria and bladder irritation persisted for over a month. Hyperbaric oxygen (HBO) therapy at 2.1 atmospheres for 90 min per day was started on day 64 after CBT. Macroscopic hematuria resolved within a week, and microscopic hematuria was no longer detectable within 2 weeks. Hematuria did not recur after 11 sessions of HBO therapy, and no significant side effects were observed during or after treatment. HBO therapy could thus be useful in controlling refractory BKV-HC after CBT.

The human polyomavirus BK (BKPyV): virological background and clinical implications

Polyomavirus BK (BKPyV) infects most people subclinically during childhood and establishes a lifelong infection in the renourinary tract. In most immunocompetent individuals, the infection is completely asymptomatic, despite frequent episodes of viral reactivation with shedding into the urine. In immunocompromised patients, reactivation followed by high-level viral replication can lead to severe disease: 1-10% of kidney transplant patients develop polyomavirus-associated nephropathy (PyVAN) and 5-15% of allogenic hematopoietic stem cell transplant patients develop polyomavirus-associated haemorrhagic cystitis (PyVHC). Other conditions such as ureteric stenosis, encephalitis, meningoencephalitis, pneumonia and vasculopathy have also been associated with BKPyV infection in immunocompromised individuals. Although BKPyV has been associated with cancer development, especially in the bladder, definitive evidence of a role in human malignancy is lacking. Diagnosis of PyVAN and PyVHC is mainly achieved by quantitative PCR of urine and plasma, but also by cytology, immunohistology and electron microscopy. Despite more than 40 years of research on BKPyV, there is still no effective antiviral therapy. The current treatment strategy for PyVAN is to allow reconstitution of immune function by reducing or changing the immunosuppressive medication. For PyVHC, treatment is purely supportive. Here, we present a summary of the accrued knowledge regarding BKPyV.

Clinical effectiveness of early treatment with hyperbaric oxygen therapy for severe late-onset hemorrhagic cystitis after hematopoietic stem cell transplantation in pediatric patients

HC is a possible cause of morbidity and extended hospitalization after HSCT. Recent studies have reported the efficiency of HOT in adult patients who underwent allogeneic HSCT, but data in children are scarce. We report our single center experience with HOT in late-onset HC after HSCT. Treatment with HOT consisted of daily sessions of breathing 100% O(2) for a total of 75 min in the hyperbaric chamber with a minimum of eight sessions. HOT had been associated with a concomitant treatment with oral oxybutynin, hyperhydration and/or irrigation of the bladder through the catheter. Cidofovir had been administered based on the demonstration of viral infection. Between 2004 and 2011, 10 patients developed severe HC after a median of 26 days after HSCT. HOT was started after a median of six days since the clinical diagnosis of HC. After a median of 10 sessions of HOT, seven of 10 patients were in complete remission. HOT is a well-tolerated procedure also in the pediatric setting. The early start of HOT might be effective in the treatment of HC offering advantages in terms of duration of symptoms and hospitalization.