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

Hyperbaric oxygen therapy in the treatment of late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation

INTRODUCTION

Hemorrhagic cystitis (HC) is a common complication after allogeneic hematopoietic stem cell transplantation (HSCT), characterized by inflammation and bleeding of the bladder. Hyperbaric oxygen therapy (HBOT) has been shown to be effective in the treatment of radiation-induced HC. However, the optimal treatment for HC after allogeneic HSCT has not yet been established. Furthermore, limited research has been conducted on the use of HBOT in this setting. This study aimed to evaluate the effectiveness and safety of HBOT in patients with late-onset HC after allogeneic HSCT.

METHODS

Twenty-five-year (1998-2022) retrospective analysis performed in all consecutive patients with confirmed late-onset HC after allogeneic HSCT treated with HBOT at two centers in Portugal. Medical records were reviewed for clinical and laboratory features, primary indications for allogeneic HSCT, conditioning regimen, and treatment strategies for HC. Patients received 100% oxygen at 2.1-2.5 atmosphere absolute pressure (ATA) for 70-90-minute periods, once daily, five times per week. Complete clinical response was defined as the absence of macroscopic hematuria sustained for at least 2 weeks, and partial response was described as a downgrading in the severity of HC. Statistical significance was considered for values of p < 0.05.

RESULTS

The sample included 61 patients with a mean age of 28.0 (SD 14.2) years, 33 males. Complete response was achieved in 72.1% (n = 44) of patients and partial response in 14.8% (n = 9). Concerning patients with a complete response, the median number of HBOT sessions was 15.5 sessions (IQR 10.0-26.8). Patients treated with 10 or more sessions of HBOT had a higher rate of complete or partial response (OR 12.5, 95%CI 1.9-83.2, p-value < 0.05). There was no response in 8 (13.1%) patients, and 6 interrupted the treatments early. Only 2 patients suspended the HBOT due to a lack of clinical benefit.

CONCLUSION

Our study supports using of HBOT as an adjunctive treatment for late-onset HC after allogeneic HSCT. Furthermore, 10 or more HBOT sessions delivered seem to impact the rate of HC resolution. Prospective, randomized, and well-controlled trials are needed to establish HBOT's definitive efficacy and safety.

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.

Treatment protocols for BK virus associated hemorrhagic cystitis after hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) represents a vital curative choice for many disease. However its outcome can be hampered by a variety of transplant associated complications. Hemorrhagic cystitis (HC) considered as one of the major difficulties after HSCT. HC symptoms comprise hematuria, dysuria, burning during urination, urinary frequency, urgency and incontinency, abdominal or suprapubic pain, urinary obstruction, and renal or bladder damage. There are a lot of causes for HC development. BK virus reactivation is one of the major causes of HC after HSCT. There is still no standard and approved treatment protocol for BK virus associated HC (BKV-HC). Treatment of HC is according to the local standard operating procedures, depending on the cause and severity. In this study we will review the current treatments available for this disease. We have divided the therapeutic procedures into 5 categories including conservative therapy, complimentary options, surgical procedures, pharmacological treatments and adoptive cell therapy. We believe that comparing the advantages and disadvantages of different therapies make it easier to choose the best treatment protocol. In addition, we had a greater focus on adoptive cell therapy, because it is a relatively new introduced method and might be a logical alternative to conventional treatments for refractory patients. In total, no definitive recommendation is possible for current available treatments because these procedures have only been utilized sporadically in a limit number of patients. Furthermore, a number of treatment options are only experimental and definitely need more effort.