Use of prophylactic anticoagulation and the risk of hepatic veno-occlusive disease in patients undergoing hematopoietic stem cell transplantation: a systematic review and meta-analysis

Kidney Disease and Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy for patients with hematologic malignancies and certain solid tumors and nonmalignant hematologic conditions. Both AKI and CKD occur commonly after HSCT and are associated with significant morbidity and mortality. AKI and CKD in this setting may result from direct effects of the transplant or be caused by pretransplant bone marrow conditioning regimens and/or nephrotoxic agents administered in the post-transplant period. In this article, we review the epidemiology, risk factors, etiologies, pathophysiology, diagnosis, prevention, and treatment of post-HSCT AKI and CKD, with special attention to recent advances in this fast-moving and evolving field.

[Clinical analysis of allogeneic hematopoietic cell transplantation in 9 patients with hematological malignancies complicated by Gilbert's syndrome]

From January 1, 2013, to March 1, 2024, nine patients with hematological malignancies complicated by Gilbert's syndrome in Peking University People's Hospital underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). The patients comprised seven male and two female cases, with a median age of 38 (13-60) years old. Among them, three cases were acute myeloid leukemia, three cases were acute lymphocytic leukemia, two cases were myelodysplastic syndrome, and one case was chronic myelomonocytic leukemia. None of the patients had viral hepatitis. Of the nine cases, seven cases received the Bu-Cy+ATG regimen, while the other two cases received the TBI-Cy+ATG regimen (Bu, busulfan; Cy, cyclophosphamide; ATG, antithymocyte immunoglobulin; and TBI, total body irradiation). All patients achieved neutrophil engraftment, and eight received platelet engraftment. The median total bilirubin level was 45.4 (22.5-71.2) μmol/L before transplantation and 22.0 (18.0-37.2) μmol/L on -1d of preconditioning. The total bilirubin level on +20d after the transplantation of eight patients decreased compared with the baseline level before transplantation. Moreover, one patient had a transient increase in the total bilirubin level on +5d after transplantation, which was considered to be attributed to the toxicity of Bu. No patients were complicated by hepatic veno-occlusive disease. The median follow-up time was 739 (42-2 491) days. During the follow-up period, one patient died of recurrence, and the remaining eight patients had disease-free survival events.

ANZTCT practice statement: sinusoidal obstruction syndrome/veno-occlusive disease diagnosis and management

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a life-threatening complication which can develop after haemopoietic stem cell transplantation (HSCT) and some antibody-drug conjugates. Several SOS/VOD diagnostic and management guidelines exist, with the most recent and refined being the European Society for Blood and Marrow Transplantation adult and paediatric guidelines. Timely diagnosis and effective management (including the availability of therapeutic options) significantly contribute to improved patient outcomes. In Australia and New Zealand, there is variability in clinical practice and access to SOS/VOD therapies. This review aims to summarise the current evidence for SOS/VOD diagnosis, prevention and treatment and to provide recommendations for SOS/VOD in the context of contemporary Australasian HSCT clinical practice.

Anticoagulant therapy likely increases risk of bleeding in Gynura segetum-induced hepatic sinus obstruction syndrome

This study aimed to analyze the clinical characteristics of Gynura segetum (Tusanqi)-induced hepatic sinusoidal obstruction syndrome (HSOS) and the benefits and risks of anticoagulant therapy for Tusanqi-induced HSOS. This was a retrospective analysis of 49 patients with Tusanqi-induced HSOS who were treated with anticoagulation or standard therapy between July 2006 and December 2022. Clinical manifestations included abdominal pain (n = 47) and peritoneal or pleural effusion (n = 46); 2 patients died. Nineteen patients requested standard medical treatment, while 30 were treated with anticoagulants. HSOS resolved within 6 months in 22 patients but did not resolve in 27 patients. The resolution rate was higher in the anticoagulant than standard treatment group (P = .037). Logistic regression analysis revealed that a history of chronic liver disease or treatment increased the risk of poor outcomes. Bleeding complications occurred in 6 patients in the anticoagulant treatment group. Early diagnosis and anticoagulant treatment are beneficial for rapid recovery after Tusanqi-induced HSOS. However, anticoagulant treatment is associated with the risk of multisite bleeding.

Evaluation of venous thromboembolism prophylaxis protocol in hematopoietic cell transplant patients

Hematopoietic cell transplant (HCT) recipients are at risk for thromboembolic and bleeding complications. There is limited evidence regarding the optimal approach to managing venous thromboembolism (VTE) prophylaxis in hospitalized patients undergoing HCT. In this retrospective cohort study, we evaluated the incidence of bleeding and VTE events in hospitalized HCT patients who received VTE prophylaxis per our institution's VTE Prophylaxis Protocol (VPP), with either enoxaparin 40 mg subcutaneously daily or heparin 5 000 units subcutaneously twice daily, compared to historical controls who did not receive VTE prophylaxis. The primary outcome was a composite of major bleeding events, clinically relevant non-major bleeding (CRNMB), and minor bleeding. The secondary outcome was a composite of VTE events. A total of 614 patients were evaluated, including 278 prior to and 336 after implementation of VPP. VTE prophylaxis resulted in no difference in bleeding events (15.1% in the pre-VPP group vs. 14.6% in the post-VPP group, p = 0.86) or composite of major and CRNMB events (0.72% vs. 0.30%, p = 0.59). There was a trend toward lower incidence of VTE events in the post-VPP group which did not reach statistical significance (8.6% vs. 6.0%, p = 0.20). We conclude that VTE prophylaxis does not pose additional bleeding risk in HCT patients.

Molecular Advances in Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) detected in the liver has been considered a severe complication of hematopoietic stem cell transplantation (HSCT). SOS/VOD is characterized by hepatomegaly, right upper quadrant pain, jaundice, and ascites. The severe forms of the disease may result in multi-organ dysfunction (MOD) with a high mortality rate (>80%). The development of SOS/VOD can be rapid and unpredictable. Therefore, early identification and severity assessment is crucial in facilitating prompt diagnosis and timely treatment. Effective treatment and potential prophylaxis with defibrotide highlight the need for characterizing a sub-group of patients at high risk for SOS/VOD. Moreover, antibodies that are conjugated with calicheamicin, gemtuzumab, and inotuzumab ozogamicin, have led to renewed interest in this syndrome. Evaluation and management of serious adverse events associated with gemtuzumab and inotuzumab ozogamicin are recommended. We review hepatic-, transplant- and patient-related risk factors, criteria for diagnosis and grading classification, and SOS/VOD potential biomarkers. Furthermore, we examine pathogenesis, clinical presentation, diagnostic criteria, risk factors, prophylaxis, and treatment of SOS/VOD occurring post HSCT. Moreover, we aim to provide an up-to-date summary of molecular advances in the diagnosis and management of SOS/VOD. We performed a comprehensive review of the literature and examined the recently available data, mostly using the PubMed and Medline search engines for original articles published over the last decade. In the era of precision medicine, our review provides up-to-date knowledge of genetic or sera markers for SOS/VOD with the goal of identifying a subset of high-risk patients.

Post-Transplantation Sinusoidal Obstruction Syndrome in Adult Patients with B Cell Acute Lymphoblastic Leukemia Treated with Pretransplantation Inotuzumab

Sinusoidal obstruction syndrome (SOS) is a potentially life-threatening complication that can be observed after allogeneic hematopoietic cell transplantation (HCT). Inotuzumab ozogamicin is an anti-CD22 monoclonal antibody-drug conjugate that has demonstrated high efficacy in relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) but is associated with an increased risk of SOS in HCT recipients. Here we aimed to examine the incidence and outcomes of SOS in 47 adult patients with R/R ALL who received inotuzumab therapy and subsequently underwent HCT at our institution. All patients received prophylactic therapy with ursodiol, and continuous low-dose heparin also was administered to patients receiving myeloablative conditioning (MAC). SOS occurred in 12 patients (26%) post-HCT, at a median onset of 11 days (range, 3 to 41 days). SOS was graded as very severe in 50% (n = 6), severe in 25% (n = 3), and mild in 25% (n = 3). All patients diagnosed with SOS received treatment with defibrotide for a median of 21 days (range, 3 to 34 days), with resolution of SOS occurring in 8 patients (67%). Mortality from SOS was 33% (n = 4) and occurred at a median of 10 days from diagnosis (range, 3 to 31 days) in patients graded as very severe (n = 3) or severe (n = 1). There were no significant differences between patients who developed SOS and those who did not develop SOS in the median time from the last dose of inotuzumab to transplantation (46 days versus 53 days; P = .37), use of an MAC regimen (42% versus 49%; P = .75), number of lines of therapy prior to inotuzumab (P = .79), median number of administered cycles of inotuzumab (2 versus 2; P = .14), or receipt of inotuzumab as the last therapy prior to HCT (67% versus 66%; P = 1.0). Sirolimus-based graft-versus-host disease (GVHD) prophylaxis was used more frequently in the SOS group (75% versus 29%; P < .01), but there was no between-group difference in the peak sirolimus level (P = .81) or the median time to peak sirolimus level (7 days versus 3.5 days; P = .39). In univariable analysis, only the use of sirolimus-based GVHD prophylaxis was significantly associated with an increased risk of SOS (hazard ratio [HR], 7.50; 95% confidence interval [CI], 1.7 to 33.6; P < .01). In the SOS group, the 100-day mortality rate was 33% (n = 4), and median overall survival (OS) post-HCT was 4.3 months (range, 0.2 to 57.2 months). In the group without SOS, the 100-day mortality rate was 14% (n = 5) and the median OS post-HCT was 10.7 months (range, .52 to 39.6 months). In this study cohort, SOS was prevalent in HCT recipients who had been treated with inotuzumab prior to transplantation, and sirolimus-based GVHD prophylaxis was a risk factor for SOS in inotuzumab recipients.

Low-dose unfractionated heparin prophylaxis is a safe strategy for the prevention of hepatic sinusoidal obstruction syndrome after myeloablative adult allogenic stem cell transplant

Hepatic sinusoidal obstruction syndrome (SOS) is a serious complication after allogeneic stem cell transplantation (allo-HCT). However, there is no uniform consensus on the optimal strategy for SOS prevention. Ursodeoxycholic acid is the most used regimen, even though its administration is challenging in recipients unable to tolerate oral medication. Defibrotide was recently studied in a phase 3 trial, but enrollment was stopped early due to futility. Low dose unfractionated heparin (UFH) is an alternative strategy. However, its efficacy is reputed but unproven increased risk of bleeding has not been fully established. We evaluated 514 adult allo-HCT recipients who received SOS prophylaxis with low dose UFH. Bleeding complications occurred in 12 patients 2.3% of patients of which only 2 (0.4%) had significant grade 3 bleeding. Only 14 patients were diagnosed with hepatic SOS. Univariate analysis showed that day 100 SOS was higher in recipients of unmodified grafts when compared to CD34+ selected ex vivo T-cell depleted grafts (p ≤ 0.001), and patients with hepatitis B and/or C exposure pre-HCT (p = 0.028). Overall, UFH was well tolerated and associated with a low incidence of subsequent hepatic SOS. Low dose UFH prophylaxis can be considered in select patients who cannot tolerate oral ursodiol.

Low Incidence of hepatic sinusoidal obstruction syndrome/veno-occlusive disease in adults undergoing allogenic stem cell transplantation with prophylactic ursodiol and low-dose heparin

Hepatic sinusoidal obstruction syndrome (SOS)/veno-occlusive disease (VOD) is a complication after allogenic hematopoietic stem-cell transplantation (allo-HSCT) with high mortality. The purpose of this study was to assess the incidence and outcome of SOS in patients after allo-HSCT with the impact of ursodeoxycholic acid (UDCA) and low-dose heparin as SOS prophylaxis. Out of 1016 patients, 23 developed SOS, with a cumulative incidence of 2.3% (95% CI 1.3-3.3) 6 months after HSCT. Approximately one quarter of these patients (26.1%) had late-onset SOS. A high proportion were very severe SOS cases (74%), and 83% of the patients were treated with defibrotide (DF). In multivariate analysis, advanced disease (p = 0.003), previous HSCT (p = 0.025) and graft versus host disease (GvHD) prophylaxis by post-transplant cyclophosphamide (PTCy) (p = 0.055) were associated with the development of SOS. The 1-year overall survival (OS) was significantly lower in the SOS group compared to patients without SOS (13% versus 70%, p = 0.0001). In conclusion, we found a low incidence of SOS in patients receiving low-dose heparin and UDCA prophylactically, but among SOS patients, a high mortality. Low-dose heparin and UDCA might be a prophylactic approach for SOS.

Hepatic sinusoidal obstruction syndrome/veno-occlusive disease after hematopoietic cell transplantation: historical and current considerations in Korea

Hepatic sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a rare but severe complication of hematopoietic cell transplantation (HCT) showing high mortality. Multiple risk factors for SOS/VOD were identified, but it is often confused with other hepatic complications due to nonspecific clinical features. Therefore, diagnostic and severity criteria have been revised several times. The European Society of Blood and Marrow Transplantation suggested a new guideline that excludes the standard duration of development within 21 days, emphasizes late-onset SOS/VOD, and suggests the importance of Doppler ultrasonography. The severity criteria were further subdivided for guidance to begin active treatment using defibrotide which was approved in Korea since 2016. In a phase 3 trial, defibrotide had superior 100-day survival, compared to best available treatments (38.2% vs. 25.0%). Although several studies of SOS/VOD in Korean patients have been performed after the implementation of HCT, most involved small number of pediatric patients. Recently, the Korean Society of Blood and Marrow Transplantation investigated the incidence of SOS/VOD in the Korean population, and several influential studies of adult patients were published. Here, we summarize recent issues regarding the mechanism, diagnosis, severity criteria, prevention, and treatments of SOS/VOD in Korean patients, as well as recent analyses of nationwide incidence.

Hepatic veno-occlusive disease development in the hematopoietic stem cell transplantation patients: incidence and associated risk factors, a meta-analysis

BACKGROUND

Now there are no efficient prophylactic or treatment strategies for hepatic veno-occlusive disease (VOD). Therefore, it is critical to early identify patients at high risk of VOD.

AIM

To analyze the risk factors of VOD in the hematopoietic stem cell transplantation (HSCT) patients.

METHODS

A comprehensive search of the population was conducted.

RESULTS

Twenty-one studies with 27 679 HSCT patients were eligible. The incidence of VOD was 15% [95% confidence interval (CI) 13-17%]. The following were the risk factors for VOD: mismatched HLA [odds ratio (OR) 2.34, 95% CI 1.20-4.57, P = 0.01], history of liver disease (OR 2.72, 95% CI 2.03-3.64, P < 0.00001), elevated AST before transplant (OR 2.49, 95% CI 1.49-4.15, P = 0.0005), months from diagnosis to HSCT > 12 months (OR 1.76, 95% CI 1.15-2.69, P = 0.009), previous radiation (OR 1.86, 95% CI 1.49-2.31, P < 0.00001), busulphan (OR 3.69, 95% CI 2.58-5.29, P < 0.00001) and MTX (OR 1.81, 95% CI 1.22-2.69, P = 0.003). There were no significant differences for VOD presentation in the patients with regards to sex, number of HSCT, Karnofsky score <90%, unrelated donor, autologous HSCT, CYA and heparin prophylaxis.

CONCLUSION

Mismatched HLA, liver disease (history of liver disease, elevated AST), months from diagnosis to HSCT >12 months, previous radiation and use of hepatotoxic drugs (BU and MTX) are the independent risk factors for VOD in the HSCT patients.

Hepatic sinusoidal obstruction syndrome caused by the ingestion of Gynura segetum in a patient with alcoholic cirrhosis: a case report

Hepatic sinusoidal obstruction syndrome (HSOS) is a rare hepatic vascular disorder characterized by intrahepatic congestion, liver injury, and post-sinusoidal portal hypertension, and it is frequently associated with hematopoietic stem cell transplantation. In this study, we observed a case of HSOS associated with the ingestion of Gynura segetum, a pyrrolizidine alkaloid (PA)-containing Chinese herb, in a patient with alcoholic cirrhosis. The patient was a 43-year-old man with chief complaints of physical asthenia and a loss of appetite for more than a month. The diagnosis of HSOS combined with alcoholic cirrhosis was confirmed via the histopathological examination of liver tissues. With proper supportive and symptomatic care and anticoagulation therapy using low-molecular-weight heparin, the patient’s condition was stabilized. Because of its nonspecific symptoms in the early stage and a lack of information about PA consumption, PA-induced HSOS (PA-HSOS) has been long neglected, especially in patients with underlying liver diseases. Early identification and intervention are critical for optimizing outcomes. Further efforts are needed to supervise the use of PA-containing herbal medicines and identify accurate biomarkers for PA-HSOS.

Incidence and risk factors of hepatic veno-occlusive disease/sinusoidal obstruction syndrome after allogeneic hematopoietic cell transplantation in adults with prophylactic ursodiol and intravenous heparin or prostaglandin E1

We attempted to identify the incidence and survival outcome of hepatic sinusoidal obstruction syndrome/veno-occlusive disease (VOD/SOS) after hematopoietic cell transplantation (HCT) under strategy of prophylactic ursodiol and intravenous heparin or prostaglandin E1 (PGE1). From 2009 to 2018, 2572 consecutive allogeneic-HCT cases were reviewed. We used oral ursodiol for all transplants, and most were administered low-dose heparin, while PGE1 in selected cases with low platelet count at the time of preconditioning. Diagnosis and severity grades were reassessed by revised EBMT criteria. The overall incidence of hepatic VOD/SOS was 3.4% (Mild 0.9%, Moderate 0.6%, Severe 0.7%, Very severe 1.2%) after allogeneic-HCT under strategy of intravenous prophylaxis. The 1-year overall survival of VOD/SOS was 41.4% which was divided into 73.9% for mild, 66.7% for moderate, 38.9% for severe, and 6.5% for very severe grade. Very high disease risk index, male gender, donor other than matched sibling donor, and busulfex > 9 mg/kg were affecting factors for development of VOD/SOS. For severe to very severe VOD/SOS, history of pre-HCT liver dysfunction was an additionally affecting factor. Allogeneic-HCT using ursodiol and intravenous prophylaxis was considered safe without significant bleeding complications and should be evaluated in future clinical trials. For those with high-risk of VOD/SOS, early intervention and management is important.

Mental health literacy in Arab states of the Gulf Cooperation Council: A systematic review

Background

Mental health literacy (MHL) has been relatively neglected, despite the increase of mental health illnesses worldwide, as well as within the Middle East region. A low level of MHL may hinder public acceptance of evidence-based mental health care.

Aim

This systematic review aims to identify and appraise existing research, focusing on MHL among adults in the Gulf Cooperation Council (GCC) countries.

Methods

A systematic search of electronic databases (PubMed, PsychInfo, and Medline) was carried out from database inception to July 2019, in order to identify peer-reviewed journal articles that investigated MHL in the GCC countries. Studies were eligible for inclusion if they were: cross-sectional studies, reported in English, targeted adults (aged 18 and above), conducted in any of the GCC countries, include at least one outcome measure of the main components of MHL: knowledge of mental illnesses and their treatment, stigmatizing attitudes towards mental illnesses, and seeking help for self and offering help.

Results

A total of 27 studies (16,391 participants) were included. The outcome across studies varied due to disparity in the tested populations. Findings show that limited MHL was observed among participants, even health care professionals. Results also show a high cumulative level of stigma and negative attitude towards mental health illness in the public. Negative beliefs and inappropriate practices are common, as well. The majority of studies yielded a moderate to high risk of bias.

Conclusion

This work indicates that research on MHL must be tackled through well-designed large-scale studies of the public. Campaigns to promote early identification and treatment of mental illness is also encouraged to improve overall level of MHL in the general population of the GCC region.

Registration number: PROSPERO 2018 CRD42018104492.

Sinusoidal obstruction syndrome

Sinusoidal obstruction syndrome (SOS), previously known as veno-occlusive disease, is characterized by concentric and non-thrombotic obstruction of the sinusoid and central vein lumen with no identified primitive or thrombotic hepatic vein lesions. The initial lesion is a result of endothelial denudation, corresponding to the migration of damaged sinusoidal cells to the central veins of the hepatic lobules, leading to sinusoidal and veno-occlusive congestive obstruction. SOS may be associated with other lesions such as centrilobular perisinusoidal fibrosis, peliosis, or nodular regenerative hyperplasia. The first cases of SOS were documented in 1920 in South Africa, after ingestion of food sources contaminated by pyrrolizidine alkaloids. SOS is a well-known complication of hematopoietic stem cell transplantation (HSCT). Numerous toxins and drugs have been associated with SOS, mainly chemotherapies and immunosuppressive therapies, as well as total body or liver irradiation and ABO mismatch platelet transfusion. The pathogenesis of this entity remains unknown.

Transjugular intrahepatic portosystemic shunt for pyrrolizidine alkaloid-related hepatic sinusoidal obstruction syndrome

BACKGROUND

Treatments for hepatic sinusoidal obstruction syndrome (HSOS) are limited.

AIM

To evaluate transjugular intrahepatic portosystemic shunting (TIPS) as a treatment for pyrrolidine alkaloid-related HSOS (PA-HSOS).

METHODS

This retrospective analysis included patients with PA-HSOS admitted to the First Affiliated Hospital of the University of Science and Technology of China (June 2015 to January 2019). Baseline clinical characteristics and follow-up data were extracted from the medical records. All patients included in this study experienced failure of initial therapy. Patients were divided into the TIPS and conservative treatment groups according to the therapy they received. Liver function, maximal ascites depth, imaging characteristics, pathology findings, and survival were compared between groups.

RESULTS

The TIPS group included 37 patients (28 males), and the conservative treatment group included 17 patients (11 males). Baseline characteristics were similar between groups. There were two deaths in the TIPS group and seven deaths in the conservative treatment group during follow-up (3-48 mo). The 3-, 6-, 12- and 24-mo survival rates were 94.6%, 94.6%, 94.6% and 94.6%, respectively, in the TIPS group and 70.6%, 57.8%, 57.8% and 57.8%, respectively, in the conservative treatment group. Kaplan-Meier analysis revealed significantly longer survival for the TIPS group than for the conservative treatment group (P = 0.001). Compared with the pre-treatment value, maximal ascites depth was significantly lower at 1 wk, 2 wk, 1 mo, and 3 mo for the TIPS group (all P < 0.05) but not in the conservative treatment group. Contrast-enhanced computed tomography demonstrated the disappearance of patchy liver enhancement after TIPS. Pathology showed that liver congestion and hepatocyte swelling improved with time after TIPS placement.

CONCLUSION

TIPS may achieve better outcomes than conventional symptomatic treatment in patients with PA-HSOS.

Diagnosis and Treatment of VOD/SOS After Allogeneic Hematopoietic Stem Cell Transplantation

Hepatic veno-occlusive disease (VOD) or sinusoidal obstruction syndrome (SOS) is a rare complication characterized by hepatomegaly, right-upper quadrant pain, jaundice, and ascites, occurring after high-dose chemotherapy, hematopoietic stem cell transplantation (HSCT) and, less commonly, other conditions. We review pathogenesis, clinical appearance and diagnostic criteria, risk factors, prophylaxis, and treatment of the VOD occurring post-HSCT. The injury of the sinusoidal endothelial cells with loss of wall integrity and sinusoidal obstruction is the basis of development of postsinusoidal portal hypertension responsible for clinical syndrome. Risk factors associated with the onset of VOD and diagnostic tools have been recently updated both in the pediatric and adult settings and here are reported. Treatment includes supportive care, intensive management, and specific drug therapy with defibrotide. Because of its severity, particularly in VOD with associated multiorgan disease, prophylaxis approaches are under investigation. During the last years, decreased mortality associated to VOD/SOS has been reported being it attributable to a better intensive and multidisciplinary approach.

Modified diagnostic criteria, grading classification and newly elucidated pathophysiology of hepatic SOS/VOD after haematopoietic cell transplantation

Sinusoidal obstruction syndrome (SOS), previously known as hepatic veno-occlusive disease (VOD), remains a multi-organ system complication following haematopoietic cell transplantation (HCT). When SOS/VOD is accompanied by multi-organ dysfunction, overall mortality rates remain >80%. However, the definitions related to the diagnosis and grading of SOS/VOD after HCT are almost 25 years old and require new and contemporary modifications. Importantly, the pathophysiology of SOS/VOD, including the contribution of dysregulated inflammatory and coagulation cascades as well as the critical importance of liver and vascular derived endothelial dysfunction, have been elucidated. Here we summarise new information on pathogenesis of SOS/VOD; identify modifiable and unmodifiable risk factors for disease development; propose novel, contemporary and panel opinion-based diagnostic criteria and an innovative organ-based method of SOS/VOD grading classification; and review current approaches for prophylaxis and treatment of SOS/VOD. This review will hopefully illuminate pathways responsible for drug-induced liver injury and manifestations of disease, sharpen awareness of risk for disease development and enhance the timely and correct diagnosis of SOS/VOD post-HCT.

Diagnosis, grading, and treatment recommendations for children, adolescents, and young adults with sinusoidal obstructive syndrome: an international expert position statement

Sinusoidal obstructive syndrome, also known as hepatic veno-occlusive disease, is a potentially life-threatening complication that occurs in children undergoing haemopoietic stem-cell transplantation (HSCT). Differences in the incidence of genetic predisposition and clinical presentation of sinusoidal obstructive syndrome between children and adults have rendered the historical Baltimore and Seattle diagnostic criteria insufficient for children. In 2017, the European Society for Blood and Marrow Transplantation (EBMT) proposed the first paediatric diagnostic and severity grading guidelines for sinusoidal obstructive syndrome, intended for implementation across European centres. However, universally accepted paediatric criteria are needed to ensure prompt diagnosis, definitive treatment, and improved outcomes for children, adolescents, and young adults with sinusoidal obstructive syndrome, and to facilitate international clinical research collaboration. We convened an international panel of multidisciplinary experts including physicians with expertise in HSCT, paediatric intensive care, nephrology, hepatology, radiology, pathology, and transfusion medicine; HSCT advanced-practice providers and medical trainees; pharmacists; and translational and basic science researchers from the Pediatric Acute Lung Injury and Sepsis Investigators Network, the EBMT, the Pediatric Blood and Marrow Transplant Consortia, and several other institutions with extensive experience in sinusoidal obstructive syndrome. Panellists convened at The University of Texas, MD Anderson Cancer Center (Houston, TX, USA) in February, 2019, to evaluate the available evidence. In this expert position statement paper, we provide consensus recommendations for the international implementation of guidelines for the diagnosis, severity grading, and treatment of sinusoidal obstructive syndrome among children, adolescents, and young adults. We endorse universal adoption of paediatric diagnostic guidelines for sinusoidal obstruction syndrome as proposed by the EBMT, and provide implementation guidance for standardisation across centres; we have further proposed adjunctive use of age-appropriate organ-specific toxicity criteria for severity grading and provided prophylaxis and treatment considerations among children and adolescent and young adult patients. Key recommendations include: (1) liver biopsy, portal venous wedge pressure, and reversal of portal venous flow on Doppler ultrasonography should not be used for the routine diagnosis of sinusoidal obstructive syndrome in children, adolescents, and young adults; (2) platelet refractoriness can be defined as a corrected count increment of less than 5000-7500 following at least two sequential ABO-compatible fresh platelet transfusions; (3) hepatomegaly is best defined as an absolute increase of at least 1 cm in liver length at the midclavicular line; and if a baseline measurement is not available, hepatomegaly can be defined as greater than 2 SDs above normal for age; and (4) the presence and volume of ascites can be categorised as mild (minimal fluid by liver, spleen, or pelvis), moderate (<1 cm fluid), or severe (fluid in all three regions with >1 cm fluid in at least two regions).

Prophylactic, preemptive, and curative treatment for sinusoidal obstruction syndrome/veno-occlusive disease in adult patients: a position statement from an international expert group

Sinusoidal obstruction syndrome, also known as veno-occlusive disease (SOS/VOD), is a potentially life-threatening complication that can develop after hematopoietic cell transplantation (HCT). While SOS/VOD may resolve within a few weeks in the majority of patients with mild-to-moderate disease, the most severe forms result in multiorgan dysfunction and are associated with a high mortality rate (>80%). Therefore, careful surveillance may allow early detection of SOS/VOD, particularly as the licensed available drug is proven to be effective and reduce mortality. The aim of this work is to propose an international consensus guideline for the treatment and prevention of SOS/VOD in adult patients, on behalf of an international expert group.

Pyrrolizidine alkaloids-induced hepatic sinusoidal obstruction syndrome: Pathogenesis, clinical manifestations, diagnosis, treatment, and outcomes

Hepatic sinusoidal obstruction syndrome (HSOS) can be caused by the intake of pyrrolizidine alkaloids (PAs). To date, PAs-induced HSOS has not been extensively studied. In view of the difference in etiology of HSOS between the West and China, clinical profiles, imaging findings, treatment, and outcomes of HSOS associated with hematopoietic stem cell transplantation or oxaliplatin might be hardly extrapolated to PAs-induced HSOS. Reactive metabolites derived from PAs form pyrrole-protein adducts that result in toxic destruction of hepatic sinusoidal endothelial cells. PAs-induced HSOS typically manifests as painful hepatomegaly, ascites, and jaundice. Laboratory tests revealed abnormal liver function tests were observed in most of the patients with PAs-induced HSOS. In addition, contrast computed tomography and magnetic resonance imaging scan show that patients with PAs-induced HSOS have distinct imaging features, which reveal that radiological imaging provides an effective noninvasive method for the diagnosis of PAs-induced HSOS. Liver biopsy and histological examination showed that PAs-induced HSOS displayed distinct features in acute and chronic stages. Therapeutic strategies for PAs-induced HSOS include rigorous fluid management, anticoagulant therapy, glucocorticoids, transjugular intrahepatic portosystemic shunt, liver transplantation, etc. The aim of this review is to describe the pathogenesis, clinical profiles, diagnostic criteria, treatment, and outcomes of PAs-induced HSOS.

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.

Soluble Thrombomodulin Attenuates Endothelial Cell Damage in Hepatic Sinusoidal Obstruction Syndrome

BACKGROUND

Hepatic sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease, is a form of drug-induced liver injury, the initial morphological changes associated with which occur in liver sinusoidal endothelial cells (LSECs). Recombinant human soluble thrombomodulin (rTM) is reported to have anti-inflammatory and cytoprotective effects. Therefore, we investigated the ability of rTM to protect endothelial cells and enhance their functions in a monocrotaline (MCT)-induced model of SOS.

MATERIALS AND METHODS

Human umbilical vein endothelial cells were assessed in vitro following administration of MCT (2-4 mM) with/without rTM (10-100 ng/ml) to investigate the effect of rTM on cell proliferation and apoptosis. In vivo experiments were performed with Crl:CD1 mice divided into three groups: rTM (rTM + MCT), placebo (control diluent + MCT), and control (control diluent only). LSECs [cluster of differentiation (CD) 31+CD34+ vascular endothelial growth factor receptor 3 (VEGFR3)+ cells] from these mice were identified using fluorescence-activated cell sorting and assessed by quantitative real-time polymerase chain reaction (qPCR).

RESULTS

In vitro, caspase-3 and -7 activities were significantly lower and cell viability (as assessed by MTT assays) significantly higher in the rTM group than in the placebo group. Moreover, levels of p-AKT increased upon rTM administration. In vivo, damage to LSECs in zone 3 of the hepatic acinus was attenuated and the number of LSECs were maintained in the rTM group, in contrast to the placebo group. Furthermore, expression of Nos3 (encoding endothelial nitric oxide synthase) was higher and that of plasminogen activator inhibitor 1 (Pai1) lower in LSECs from mice in the rTM group than in those from the placebo group.

CONCLUSION

rTM can attenuate SOS by protecting LSECs and enhancing their functions.

New Ultrasound Techniques Challenge the Diagnosis of Sinusoidal Obstruction Syndrome

Sinusoidal obstruction syndrome, also known as veno-occlusive disease (SOS/VOD), is a potentially life-threatening complication that can develop after hematopoietic cell transplantation. Clinically, SOS/VOD is characterized by hepatomegaly, right upper quadrant pain, jaundice and ascites, most often occurring within the first 3 wk after hematopoietic cell transplantation. Early therapeutic intervention is pivotal for survival in SOS/VOD. Thus, a rapid and reliable diagnosis has to be made. Diagnosis of SOS/VOD is based on clinical criteria, such as the Seattle, Baltimore or recently issued European Society for Blood and Marrow Transplantation criteria, to which hemodynamic and/or ultrasound evidence of SOS were added for the first time. However, to rule out major differential diagnoses and to verify the diagnosis, a reliable imaging method is needed. Ultrasound techniques have been proposed in SOS/VOD. Nevertheless, the sensitivity and specificity of transabdominal ultrasound and Doppler techniques need to be improved. Innovative ultrasound methods such as a combination of Doppler ultrasound with shear wave elastography and contrast-enhanced ultrasound techniques should be evaluated for diagnosis and follow-up of SOS/VOD. The goals of this review are to discuss currently available ultrasound techniques and to identify areas for future studies in SOS/VOD.

Defibrotide sodium for the treatment of hepatic veno-occlusive disease/sinusoidal obstruction syndrome

INTRODUCTION

Hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is an unpredictable condition associated with endothelial-cell damage due to conditioning for hematopoietic stem-cell transplantation (HSCT) or chemotherapy without HSCT. Mortality in patients with VOD/SOS and multi-organ dysfunction (MOD) may be >80%. Areas covered: Defibrotide is the only approved drug for the treatment of severe hepatic VOD/SOS after HSCT in the European Union and hepatic VOD/SOS with renal or pulmonary dysfunction in the United States. Its efficacy in patients with VOD/SOS with MOD post-HSCT was demonstrated in a clinical-trial program that included a historically controlled treatment study, a phase 2 trial, and a large T-IND expanded-access program that also included patients without MOD and who received chemotherapy without HSCT. Expert commentary: Defibrotide appears to protect endothelial cells and restore the thrombolytic-fibrinolytic balance. It addresses a significant clinical need and has demonstrated favorable Day +100 survival and overall adverse-event rates that seem similar to control groups receiving supportive care alone. Currently, defibrotide is under investigation for the prevention of VOD/SOS in high-risk pediatric and adult patients.

Defibrotide for the treatment of hepatic veno-occlusive disease/sinusoidal obstruction syndrome with multiorgan failure

Hepatic veno-occlusive disease, also called sinusoidal obstruction syndrome (VOD/SOS), is a potentially life-threatening and unpredictable complication of hematopoietic stem cell transplantation (HSCT). Characterized by a prothrombotic-hypofibrinolytic state, VOD/SOS typically presents with hyperbilirubinemia, ascites, weight gain and painful hepatomegaly; VOD/SOS with multiorgan failure may be associated with >80% mortality. Treatment has been mainly supportive. However, defibrotide is now approved in the USA for treatment of hepatic VOD/SOS with renal or pulmonary dysfunction following HSCT and in the European Union for treatment of severe hepatic VOD/SOS post-HSCT. In vitro evidence suggests defibrotide may restore thrombotic-fibrinolytic balance at the endothelial level and protect endothelial cells. Defibrotide has demonstrated significant reduction in VOD/SOS-related mortality and resolved VOD/SOS-related symptoms, with a manageable safety profile.

Defibrotide for children and adults with hepatic veno-occlusive disease post hematopoietic cell transplantation

Hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a complication that is typically associated with conditioning for hematopoietic stem cell transplantation (HSCT). In patients with concomitant multi-organ dysfunction, mortality may be >80%. Recently, the European Society for Blood and Marrow Transplantation established separate criteria for diagnosis and severity of VOD/SOS for adults and children, to better reflect current understanding of the disease. Areas covered: This review provides an overview of post-HSCT hepatic VOD/SOS and defibrotide, including its pharmacological, clinical, and regulatory profile. In children and adults following HSCT, defibrotide is approved for the treatment of hepatic VOD/SOS with concomitant renal or pulmonary dysfunction in the United States and for the treatment of severe hepatic VOD/SOS in the European Union. Day +100 survival rates with defibrotide are superior to those of historical controls receiving best supportive care only, and safety profiles are similar. Expert commentary: Defibrotide appears to act through multiple mechanisms to restore thrombo-fibrinolytic balance and protect endothelial cells, and there are promising data on the use of defibrotide for VOD/SOS prophylaxis in high-risk children undergoing HSCT. An ongoing randomized controlled trial in children and adults will better assess the clinical value of defibrotide as a preventive medication.

Consensus Report by Pediatric Acute Lung Injury and Sepsis Investigators and Pediatric Blood and Marrow Transplantation Consortium Joint Working Committees: Supportive Care Guidelines for Management of Veno-Occlusive Disease in Children and Adolescents, Part 1: Focus on Investigations, Prophylaxis, and Specific Treatment

Veno-occlusive disease (VOD) is a common and potentially fatal complication in children undergoing hematopoietic cell transplantation (HCT). It occurs in about one-third of all patients undergoing transplantation and is fatal in 50% of patients with severe disease. Early intervention and specific treatment with defibrotide are associated with improved outcomes. However, there is a lack of supportive care guidelines for management of the multiorgan dysfunction seen in most cases. There is high variability in the management of VOD, which may contribute to the increased morbidity and mortality. Although there is ample research in the specific treatment of VOD, there is paucity of literature regarding the management of ascites, transfusions requirements, fluids and electrolyte dysfunction, delirium, and investigations in children with VOD. The joint working committees of the Pediatric Acute Lung Injury and Sepsis Investigators and the Pediatric Blood and Marrow Transplantation Consortium collaborated to develop a series of evidence-based supportive care guidelines for management of VOD. The quality of evidence was rated and recommendations were made using Grading of Recommendations, Assessment, Development and Evaluation criteria. This manuscript is part 1 of the series and focuses on the need to develop these guidelines; methodology used to establish the guidelines; and investigations needed for diagnosis, prophylaxis, and treatment of VOD in children.

Defibrotide for the Treatment of Hepatic Veno-Occlusive Disease: Final Results From the International Compassionate-Use Program

Hepatic veno-occlusive disease, also called sinusoidal obstruction syndrome (VOD/SOS), is an unpredictable and potentially fatal complication of hematopoietic cell transplantation (HCT) or nontransplantation-associated chemotherapy/radiotherapy. In cases of severe hepatic VOD/SOS, typically defined by associated multiorgan failure (MOF, also known as multiorgan dysfunction), mortality exceeds 80%. Preclinical and early clinical data have provided a rationale for defibrotide treatment in hepatic VOD/SOS. Based on this evidence and in recognition of the dismal prognosis for these patients, defibrotide was made available through an international multicenter compassionate-use program conducted from December 1998 to March 2009. Physicians participating in the program voluntarily provided demographic and outcome data for patients given defibrotide. Efficacy and safety analyses were performed using the data received for 710 treated patients. Defibrotide was given at 10, 25, 40, 60, or 80 mg/kg/day for a median of 15 days (range, 1 to 119 days). By Kaplan-Meier analysis, the estimated overall day +100 survival was 54% (58% in the 25 mg/kg/day dose group). Adverse events (AEs) were reported in 53% of patients. The most common AEs were MOF, progression of hepatic VOD/SOS, sepsis, and graft-versus-host disease, which were consistent with the AEs expected for this patient population. No clinically meaningful trends in AEs were identified by gender, age, or dose group. Safety and efficacy resultswere consistent with prior studies of defibrotide in hepatic VOD/SOS, and subgroup analyses lend support to the use of the 25 mg/kg/day dose.

Hepatic Veno-Occlusive Disease after Hematopoietic Stem Cell Transplantation: Risk Factors and Stratification, Prophylaxis, and Treatment

Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), can develop in a subset of patients, primarily after myeloablative hematopoietic stem cell transplantation, but it also may occur after reduced-intensity conditioning. Severe VOD/SOS, typically characterized by multiorgan failure, has been associated with a mortality rate greater than 80%. Therefore, an accurate and prompt diagnosis of VOD/SOS is essential for early initiation of appropriate therapy to improve clinical outcomes. Moreover, some studies have support the use of prophylaxis for patients who are at high risk of developing VOD/SOS. This review summarizes risk factors associated with development of VOD/SOS, including pretransplantation patient characteristics and factors related to stem cell transplantation, that can facilitate patient stratification according to risk. The incidence of VOD/SOS, clinical features, and diagnostic criteria are reviewed. Data on emerging treatment strategies for patients with VOD/SOS are discussed in the context of recent treatment guidelines. Additionally, options for prophylaxis in individuals who are at increased risk are presented. Although historically only those patients with moderate to severe VOD/SOS have been treated, early therapy and prophylaxis may be appropriate for many patients and may have the potential to improve patients' outcomes and survival, including for those with nonsevere disease.

Prophylaxis and treatment recommendations for sinusoidal obstruction syndrome in adult and pediatric patients undergoing hematopoietic stem cell transplant: a review of the literature

Sinusoidal obstruction syndrome, a complication occurring early after hematopoietic stem cell transplantation, is a concern for clinicians. There are no guidelines to direct clinicians on the optimal way to prevent and treat this disease. Newer data show that defibrotide is a promising drug both for prevention and treatment, although it is not yet FDA approved.

Interventions for prophylaxis of hepatic veno-occlusive disease in people undergoing haematopoietic stem cell transplantation

BACKGROUND

Hepatic veno-occlusive disease (VOD) is a severe complication after haematopoietic stem cell transplantation (HSCT). Different drugs with different mechanisms of action have been tried in HSCT recipients to prevent hepatic VOD. However, it is uncertain whether high-quality evidence exists to support any prophylactic therapy.

OBJECTIVES

We aimed to determine the effects of various prophylactic therapies on the incidence of hepatic VOD, overall survival, mortality, quality of life (QOL), and the safety of these therapies in people undergoing HSCT.

SEARCH METHODS

We searched the Cochrane Central Registe of Controlled Trials (CENTRAL), MEDLINE, EMBASE, conference proceedings of three international haematology-oncology societies and two trial registries in January 2015, together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing prophylactic therapies with placebo or no treatment, or comparing different therapies for hepatic VOD in people undergoing HSCT.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 14 RCTs. Four trials (612 participants) compared ursodeoxycholic acid with or without additional treatment versus placebo or no treatment or same additional treatment. Two trials (259 participants) compared heparin with no treatment. Two trials (106 participants) compared low molecular weight heparin (LMWH) with placebo or no treatment. One trial (360 participants) compared defibrotide with no treatment. One trial (34 participants) compared glutamine with placebo. Two trials (383 participants) compared fresh frozen plasma (FFP) with or without additional treatment versus no treatment or same additional treatment. One trial (30 participants) compared antithrombin III with heparin versus heparin. One trial compared heparin (47 participants) with LMWH (46 participants) and prostaglandin E1 (PGE1) (47 participants). No trial investigated the effects of danaparoid. The RCTs included participants of both genders with wide age range and disease spectrum undergoing autologous or allogeneic HSCT. Funding was provided by government sources (two studies), research fund (one study), pharmaceutical companies that manufactured defibrotide and ursodeoxycholic acid (two studies), or unclear source (nine studies). All RCTs had high risk of bias because of lack of blinding of participants and study personnel, or other risks of bias (mainly differences in baseline characteristics of comparison groups).Results showed that ursodeoxycholic acid may reduce the incidence of hepatic VOD (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.40 to 0.88; number needed to treat for an additional beneficial outcome (NNTB) 15, 95% CI 7 to 50, low quality of evidence), but there was no evidence of difference in overall survival (hazard ratio (HR) 0.83, 95% CI 0.59 to 1.18, low quality of evidence). It may reduce all-cause mortality (RR 0.70, 95% CI 0.50 to 0.99; NNTB 17, 95% CI 8 to 431, low quality of evidence) and mortality due to hepatic VOD (RR 0.27, 95% CI 0.09 to 0.87; NNTB 34, 95% CI 16 to 220, very low quality of evidence). There was no evidence of difference in the incidence of hepatic VOD between treatment and control groups for heparin (RR 0.47, 95% CI 0.18 to 1.26, very low quality of evidence), LMWH (RR 0.27, 95% CI 0.06 to 1.18, very low quality of evidence), defibrotide (RR 0.62, 95% CI 0.38 to 1.02, low quality of evidence), glutamine (no hepatic VOD in either group, very low quality of evidence), FFP (RR 0.66, 95% CI 0.20 to 2.17, very low quality of evidence), antithrombin III (RR 0.13, 95% CI 0.01 to 2.15, very low quality of evidence), between heparin and LMWH (RR 1.96, 95% CI 0.80 to 4.77, very low quality of evidence), between heparin and PGE1 (RR 1.20, 95% CI 0.58 to 2.50, very low quality of evidence), and between LMWH and PGE1 (RR 0.61, 95% CI 0.24 to 1.55, very low quality of evidence). There was no evidence of difference in survival between treatment and control groups for heparin (92.6% vs. 88.7%) and defibrotide (HR 1.04, 95% CI 0.54 to 2.02, low quality of evidence). There were no data on survival for trials of LMWH, glutamine, FFP, antithrombin III, between heparin and LMWH, between heparin and PGE1, and between LMWH and PGE1. There were no data on quality of life (QoL) for any trials. Eleven trials reported adverse events. There was no evidence of difference in the frequency of adverse events between treatment and control groups except for one trial showing that defibrotide resulted in more adverse events compared with no treatment (RR 18.79, 95% CI 1.10 to 320.45). These adverse events included coagulopathy, gastrointestinal disorders, haemorrhage and microangiopathy. The quality of evidence was low or very low due to bias of study design, and inconsistent and imprecise results.

AUTHORS' CONCLUSIONS

There is low or very low quality evidence that ursodeoxycholic acid may reduce the incidence of hepatic VOD, all-cause mortality and mortality due to VOD in HSCT recipients. However, the optimal regimen is not well-defined. There is insufficient evidence to support the use of heparin, LMWH, defibrotide, glutamine, FFP, antithrombin III, and PGE1. Further high-quality RCTs are needed.

A retrospective analysis of outcomes of dalteparin use in pediatric patients: a single institution experience

BACKGROUND

Dalteparin is a commonly used low molecular weight heparin (LMWH) with extensive safety data in adults. With distinct advantages of once daily dosing and relative safety in renal impairment, it has been used off-label in pediatric practice; however, age-based dosing guidelines, safety and efficacy data in children are evolving.

OBJECTIVES

To report our institutional experience with the use of dalteparin in the treatment and prophylaxis of venous thromboembolism (VTE) in pediatric patients.

PATIENTS/METHODS

Retrospective chart review of all children (0-18years) that received dalteparin from December 1, 2000 through December 31, 2011. Doses per unit body weight per day (units/kg/day) were calculated for age-based group comparisons.

RESULTS

Of 166 patients identified, 116 (70%) received prophylactic doses while 50 (30%) received therapeutic doses of dalteparin. Infants (<1year) required significantly higher weight-based dosing to achieve therapeutic anti-Xa levels compared to children (1-10years) or adolescents (>10-18years) (mean dose units/kg/day; 396.6 versus 236.7 and 178.8 respectively, p<0.0001). Overall response rate, including complete and partial thrombus resolution, was 83%. Bleeding complications were minor and the rates were similar in therapeutic and prophylaxis patients. No significant differences in dosing or bleeding events were noted based on obesity or malignancy.

CONCLUSIONS

In our experience, dalteparin is effective for prophylaxis and therapy of VTE in pediatric patients. Dosing should be customized in an age-based manner with close monitoring of anti-Xa activity in order to achieve optimal levels, prevent bleeding complications, and to allow full benefit of prevention or therapy of thrombotic complications.

Sinusoidal obstruction syndrome/veno-occlusive disease: current situation and perspectives-a position statement from the European Society for Blood and Marrow Transplantation (EBMT)

Sinusoidal obstruction syndrome or veno-occlusive disease (SOS/VOD) is a potentially life-threatening complication of hematopoietic SCT (HSCT). This review aims to highlight, on behalf of the European Society for Blood and Marrow Transplantation, the current knowledge on SOS/VOD pathophysiology, risk factors, diagnosis and treatments. Our perspectives on SOS/VOD are (i) to accurately identify its risk factors; (ii) to define new criteria for its diagnosis; (iii) to search for SOS/VOD biomarkers and (iv) to propose prospective studies evaluating SOS/VOD prevention and treatment in adults and children.

How I manage sinusoidal obstruction syndrome after haematopoietic cell transplantation

Sinusoidal obstruction syndrome (SOS), also called veno-occlusive disease of the liver, is one of the most relevant complications of endothelial origin that appears early after haematopoietic cell transplantation (HCT). Despite its relatively low incidence and the fact that most cases of SOS resolve spontaneously, the cases that evolve to multi-organ failure (MOF; severe SOS) have a mortality rate higher than 80% and represent one of the major clinical problems after HCT. For this reason, transplantation teams must have a pre-established policy regarding preventive measures in high-risk patients, strict daily control of weight and fluid balance during HCT, homogeneous diagnostic criteria, appropriate complementary studies for a correct differential diagnosis and measures to prevent and manage hepatorenal syndrome; in addition they must also be ready to start early treatment with defibrotide in patients with a possible severe SOS. Due to the lack of definitive evidence to enable the establishment of general recommendations in the management of SOS, this review analyses all of these aspects based on the author's personal experience.

BCSH/BSBMT guideline: diagnosis and management of veno-occlusive disease (sinusoidal obstruction syndrome) following haematopoietic stem cell transplantation

DIAGNOSIS

It is recommended that the diagnosis of veno-occlusive disease (sinusoidal obstruction syndrome) [VOD (SOS)] be based primarily on established clinical criteria (modified Seattle or Baltimore criteria) (1A). Ultrasound imaging may be helpful in the exclusion of other disorders in patients with suspected VOD (SOS) (1C). It is recommended that liver biopsy be reserved for patients in whom the diagnosis of VOD (SOS) is unclear and there is a need to exclude other diagnoses (1C). It is recommended that liver biopsies are undertaken using the transjugular approach in order to reduce the risks associated with the procedure (1C). It is suggested that the role of plasminogen activator inhibitor 1 levels remains an area for further research but that these levels should not form part of the routine diagnostic work-up for VOD (SOS) at present (2C).

RISK FACTORS

It is recommended that patients are assessed for risk factors for VOD (SOS) and that these risk factors are addressed prior to haematopoietic stem cell transplantation (1A).

PROPHYLAXIS

Defibrotide is recommended at a dose of 6.25 mg/kg intravenously four times daily for the prevention of VOD (SOS) in children undergoing allogeneic stem cell transplantation with the following risk factors: pre-existing hepatic disease, second myeloablative transplant, allogeneic transplant for leukaemia beyond second relapse, conditioning with busulfan-containing regimens, prior treatment with gemtuzumab ozogamicin, diagnosis of primary haemophagocytic lymphohistiocytosis, adrenoleucodystrophy or osteopetrosis (1A). Defibrotide is suggested at a dose of 6.25 mg/kg intravenously four times daily for the prevention of VOD (SOS) in adults undergoing allogeneic stem cell transplantation with the following risk factors: pre-existing hepatic disease, second myeloablative transplant, allogeneic transplant for leukaemia beyond second relapse, conditioning with busulfan-containing regimens, prior treatment with gemtuzumab ozogamicin, diagnosis of primary haemophagocytic lymphohistiocytosis, adrenoleucodystrophy or osteopetrosis (2B). Prostaglandin E1 is not recommended in the prophylaxis of VOD (SOS) due to lack of efficacy and toxicity (1B). Pentoxifylline is not recommended in the prophylaxis of VOD (SOS) due to lack of efficacy (1A). Ursodeoxycholic acid is suggested for use in the prophylaxis of VOD (SOS) (2C). Heparin (unfractionated and low molecular weight) is not suggested for use in the prophylaxis of VOD (SOS) due to the risk of increased toxicity (2B). Antithrombin is not suggested for the prophylaxis of VOD (SOS) due to lack of efficacy (2B).

TREATMENT

Defibrotide is recommended in the treatment of VOD (SOS) in adults and children (1B). Tissue plasminogen activator is not recommended for use in the treatment of VOD (SOS) due to the associated risk of haemorrhage (1B). N-acetylcysteine is not routinely recommended for use in the treatment of veno-occlusive disease due to lack of efficacy (1A). Methylprednisolone may be considered for use in the treatment of veno-occlusive disease with the appropriate caveats of caution regarding infection (2C). Judicious clinical care, particularly in the management of fluid balance, is recommended in the management of VOD (SOS) (1C). Early discussion with critical care specialists and a specialist hepatology unit is recommended in the management of VOD (SOS) and other treatment options including transjugular intrahepatic portosystemic shunt or hepatic transplantation may be considered (1C).

SUMMARY

A joint working group established by the Haemato-oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Society for Blood and Marrow Transplantation (BSBMT) has reviewed the available literature and made recommendations for the diagnosis and management of veno-occlusive disease of the liver following haematopoietic stem cell transplantation (HSCT). This guideline includes recommendations for both prophylaxis and treatment of the condition and includes recommendations for children and adults undergoing HSCT.

Role of anticoagulant therapy in liver disease

Anticoagulant therapy is a cornerstone in the treatment of different liver diseases. In Budd-Chiari syndrome (BCS), survival rates have increased considerably since the introduction of a treatment strategy in which anticoagulation is the treatment of first choice. In all patients diagnosed with acute portal vein thrombosis (PVT), anticoagulant therapy for at least 3 months is indicated. Anticoagulation should also be considered in patients with chronic PVT and a concurrent prothrombotic risk factor. Current evidence suggests that patients with PVT in cirrhosis will benefit from treatment with anticoagulation as well. In severe chronic liver disease the levels of both pro- and anticoagulant factors are decreased, resetting the coagulant balance in an individual patient and making it more prone to deviate to a hypo- or hypercoagulable state. An increased activity of the coagulation cascade is not solely a feature of chronic liver disease; it influences the development of liver fibrosis as well. Several studies in animals and humans have shown that anticoagulation could prevent or improve fibrogenesis and even disease progression in cirrhosis. Anticoagulation is therefore a promising antifibrotic treatment modality.