The relevance of plasminogen activator inhibitor 1 (PAI-1) as a marker for the diagnosis of hepatic veno-occlusive disease in patients after bone marrow transplantation

Hypofibrinolysis in pediatric patients with veno-occlusive disease in hematopoietic stem cell transplantation

PURPOSE

Veno-occlusive disease (VOD) is a serious complication of hematopoietic stem cell transplantation (HSCT) with a high incidence in pediatric patients. This study aimed to detect signs of hypofibrinolysis using thrombelastography.

METHODS

In this prospective single-center study, thrombelastographic measurements (EX and TPA tests) were taken during HSCT to detect signs of impaired coagulation, clot formation, or hypofibrinolysis.

RESULTS

Of 51 patients undergoing allogeneic and autologous HSCT, five (9.8%) developed VOD and received defibrotide treatment. Thrombelastography measurements were also obtained from 55 healthy children as a control group. The results show that clot lysis was prolonged in VOD patients compared to other HSCT patients and control group (lysis time, TPA test: day + 14 to + 21: VOD: 330 ± 67 s vs. HSCT: 246 ± 53 s; p = 0.0106; control: 234 ± 50 s; control vs. VOD: p = 0.0299). The maximum lysis was reduced in HSCT patients compared to controls (EX test: control: 8.3 ± 3.2%; HSCT: day 0 to + 6: 5.3 ± 2.6%, p < 0.0001; day + 7 to + 13: 3.9 ± 2.1%, p < 0.0001; day + 14 to d + 21: 4.1 ± 2.3%, p < 0.0001).

CONCLUSION

These results suggest that HSCT patients exhibit reduced fibrinolytic capacities and patients diagnosed with VOD show signs of hypofibrinolysis. This prospective study shows that fibrinolysis can be assessed in a rapid and accessible way via thrombelastography. Thrombelastography might be a parameter to support the diagnosis of a VOD and to serve as a follow-up parameter after the diagnosis of a VOD.

Endothelial Dysfunction after Hematopoietic Stem Cell Transplantation: A Review Based on Physiopathology

Endothelial dysfunction (ED) is frequently encountered in transplant medicine. ED is an argument of high complexity, and its understanding requires a wide spectrum of knowledge based on many fields of basic sciences such as molecular biology, immunology, and pathology. After hematopoietic stem cell transplantation (HSCT), ED participates in the pathogenesis of various complications such as sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), graft-versus-host disease (GVHD), transplant-associated thrombotic microangiopathy (TA-TMA), idiopathic pneumonia syndrome (IPS), capillary leak syndrome (CLS), and engraftment syndrome (ES). In the first part of the present manuscript, we briefly review some biological aspects of factors involved in ED: adhesion molecules, cytokines, Toll-like receptors, complement, angiopoietin-1, angiopoietin-2, thrombomodulin, high-mobility group B-1 protein, nitric oxide, glycocalyx, coagulation cascade. In the second part, we review the abnormalities of these factors found in the ED complications associated with HSCT. In the third part, a review of agents used in the treatment of ED after HSCT is presented.

Endothelial cell function and endothelial-related disorders following haematopoietic cell transplantation

Use of haematopoietic cell transplantation (HCT) in the treatment of haematologic and neoplastic diseases may lead to life-threatening complications that cause substantial morbidity and mortality if untreated. In addition to patient- and disease-related factors, toxicity associated with HCT puts patients at risk for complications that share a similar pathophysiology involving endothelial cells (ECs). Normally, the endothelium plays a role in maintaining homeostasis, including regulation of coagulation, vascular tone, permeability and inflammatory processes. When activated, ECs acquire cellular features that may lead to phenotypic changes that induce procoagulant, pro-inflammatory and pro-apoptotic mediators leading to EC dysfunction and damage. Elevated levels of coagulation factors, cytokines and adhesion molecules are indicative of endothelial dysfunction, and endothelial damage may lead to clinical signs and symptoms of pathological post-HCT conditions, including veno-occlusive disease/sinusoidal obstruction syndrome, graft-versus-host disease, transplant-associated thrombotic microangiopathy and idiopathic pneumonia syndrome/diffuse alveolar haemorrhage. The endothelium represents a rational target for preventing and treating HCT complications arising from EC dysfunction and damage. Additionally, markers of endothelial damage may be useful in improving diagnosis of HCT-related complications and monitoring treatment effect. Continued research to effectively manage EC activation, injury and dysfunction may be important in improving patient outcomes after HCT.

Hepatic Sinusoidal-obstruction Syndrome and Busulfan-induced Lung Injury in a Post-autologous Stem Cell Transplant Recipient

Veno-occlusive disease of the liver is mostly encountered as a complication of hematopoietic stem cell transplantation with myeloablative regimens with an incidence estimated to be 13.7%. It is clinically characterized by tender hepatomegaly, jaundice, weight gain and ascites. Strong clinical suspicion and an early recognition of clinical signs are essential to establish the diagnosis and institute effective regimen. Another complication of cytotoxic drugs given for cancers, is development of busulfan-induced lung injury. A strong index of suspicion is needed for its diagnosis, especially in setting where opportunistic fungal and viral infections manifest similarly. We illustrate the clinical and autopsy finings in a 2½-year-old boy who received autologous stem-cell transplantation following resection of stage IV neuroblastoma. He subsequently developed both hepatic veno-occlusive disease and busulfan-induced lung injury. The autopsy findings are remarkable for their rarity.

Chlorogenic acid suppresses monocrotaline-induced sinusoidal obstruction syndrome: The potential contribution of NFκB, Egr1, Nrf2, MAPKs and PI3K signals

Hepatic sinusoidal obstruction syndrome (SOS) is a highly lethal liver disease. This study aims to observe the protection and its engaged mechanism of chlorogenic acid (CGA) against monocrotaline (MCT)-induced SOS. Results of detecting liver ascites, measuring serum transaminases, liver histological evaluation and scanning electron microscope observation all demonstrated that CGA prevented MCT-induced SOS in rats. CGA reduced MCT-induced increased liver myeloperoxidase (MPO) activity, tumor necrosis factor (TNF)α and interleukin (IL)-1β mRNA expression, toll-like receptor (TLR)-2,3,6,9 expression, and nuclear factor κB (NFκB) transcriptional activation. CGA also decreased MCT-induced early growth response1 (Egr1) activation. CGA reduced MCT-induced elevated liver malondialdehyde (MDA) amount and enhanced nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2). CGA blocked MCT-induced PI3K and MAPKs activation. In conclusion, this study demonstrates the protection of CGA against MCT-induced SOS. Transcriptional factor NFκB, Egr1 and Nrf2-regulated inflammation, coagulation-fibrinolysis, and antioxidant, and PI3K and MAPKs all contribute to such protection.

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.

Veno-occlusive disease in hematopoietic stem cell transplantation recipients

Veno-occlusive disease (VOD) is a potentially fatal complication of hematopoietic stem cell transplantation that affects the liver, as well as other organs. Although mild cases resolve on their own, severe cases of VOD carry a high mortality rate. The diagnosis usually is clinically based, with nonspecific signs such as weight gain, ascites, hepatomegaly, right upper quadrant abdominal pain, and elevated serum bilirubin. Although studies are ongoing, no U.S. Food and Drug Administration-approved treatments for VOD exist to date. Therefore, supportive care is a critical part of the treatment plan. Oncology nurses should be familiar with the risk factors and clinical signs of VOD so that patients can be monitored closely for its occurrence. Accurate and timely recognition of VOD is crucial for appropriate treatment.

Contribution of fibrinolytic tests to the differential diagnosis of veno-occlusive disease complicating pediatric hematopoietic stem cell transplantation

BACKGROUND

Veno-occlusive disease (VOD) is a major complication following hematopoietic stem cell transplantation (HSCT). Its diagnosis is based on clinical criteria, which have a limited sensitivity. Increased plasminogen activator inhibitor-1 (PAI-1) levels have been suggested as a marker of VOD. We aimed to prospectively evaluate how the fibrinolytic parameters behaved to discriminate VOD from other liver disorders occurring after HSCT in a pediatric population.

PROCEDURES

A total of 195 HSCT were performed on 161 children and VOD complicated 11 cases (6.8%). Alanine aminotransferase, total bilirubin, PAI-1 antigen (PAI-1:Ag) and activity, t-PA antigen, D-dimer, prothrombin time, activated partial thromboplastin time, antithrombin, fibrinogen, and platelet counts were measured in 105 HSCT before and then weekly for 1 month after HSCT.

RESULTS

An early, significant increase in the fibrinolytic parameters was seen in patients who developed VOD, even before VOD was diagnosed clinically, by comparison with patients without complications or those with non-VOD liver disorders. The combined increase in bilirubin, D-dimer, and PAI-1:Ag levels beyond the normal range distinguished VOD cases from other liver complications with a high sensitivity and specificity.

CONCLUSIONS

Our study demonstrates that fibrinolytic tests can help diagnose VOD after HSCT in the pediatric population.

Hepatic veno-occlusive disease after tranexamic acid administration in patients undergoing allogeneic hematopoietic stem cell transplantation

Tranexamic acid is one of the widely used antifibrinolytic agents. In spite of its effective inhibitory activity against plasminogen, thromboembolic adverse events caused by tranexamic acid are rare. We encountered three recipients of allogeneic hematopoietic stem cell transplantation (HSCT) who developed hepatic veno-occlusive disease (VOD) shortly after the administration of tranexamic acid. Hepatic VOD was resolved completely in all patients with the discontinuation of the drug, and with supportive measures with or without intravenous tissue plasminogen activator administration. These findings suggest that administration of tranexamic acid could be one of the possible risk factors for developing hepatic VOD in HSCT recipients.

Review article: updates in the pathogenesis and therapy of hepatic sinusoidal obstruction syndrome

Hepatic sinusoidal obstruction syndrome is frequently linked to high-dose chemotherapy/total-body irradiation in recipients of haematopoietic stem cell transplantation, long-term use of azathioprine after organ transplantation and other chemotherapeutic agents. The incidence of hepatic sinusoidal obstruction syndrome varies from 0% to 70%, and is decreasing. Disease risk is higher in patients with malignancies, hepatitis C virus infection, those who present late, when norethisterone is used to prevent menstruation, and when broad-spectrum antibiotics and antifungals are used during and after the conditioning therapy. Hepatic sinusoidal obstruction syndrome presents with tender hepatomegaly, hyperbilirubinaemia and ascites, and diagnosis is mainly clinical (Seattle and Baltimore Criteria). Imaging excludes biliary obstruction and malignancy, but cannot establish accurate diagnosis. Hepatic sinusoidal obstruction syndrome may be prevented by avoiding the highest risk regimens, using non-myelo-ablative regimens, and reducing total-body irradiation dose. Treatment is largely symptomatic and supportive, because 70-80% of patients recover spontaneously. Tissue plasminogen activator plus heparin improves outcome in <30% of cases. Defibrotide, a polydeoxyribonucleotide, is showing encouraging results. Transjugular intrahepatic porto-systemic shunt relieves ascites, but does not improve outcome. Liver transplantation may be an option in the absence of malignancy. Prognosis is variable and depends on disease severity, aetiology and associated conditions. Death is most commonly caused by renal or cardiopulmonary failure.

Diagnosis of Hepatic Veno-occlusive Disease by Plasminogen Activator Inhibitor-1 Plasma Antigen Levels: A Prospective Analysis in 350 Allogeneic Hematopoietic Stem Cell Recipients

BACKGROUND

Veno-occlusive disease (VOD) is one of the most serious complications following allogeneic hematopoietic stem cell transplantation (HSCT) and is associated with a high mortality. We conducted a large trial in order to investigate the value of plasminogen activator inhibitor-1 (PAI-1) plasma antigen levels in VOD patients as PAI-1 has been described as a possible diagnostic marker of VOD.

METHODS

In all, 350 stem cell recipients were included in our study. PAI-1 levels were analyzed prior to conditioning therapy and then weekly until eight weeks after HSCT. Transplantation-related complications (TRC) including VOD, microangiopathic hemolytic anemia (MAHA), and graft-versus-host disease (GVHD) were recorded weekly throughout the study.

RESULTS

Maximum PAI-1 antigen levels were increased in all patients with VOD (n=15; mean 248 ng/ml; 95% CI 183-314 ng/ml). Maximum PAI-1 levels above 120 ng/ml showed a sensitivity of 100% and a specificity of 30.6% for VOD after HSCT.

CONCLUSION

Our study underlines that maximum PAI-1 plasma antigen levels not exceeding 120 ng/ml have a strong negative predictive value in the diagnosis of VOD and thus represent a helpful non-invasive tool for exclusion of VOD after HSCT.

Transforming growth factor beta-1 released from platelets contributes to hypercoagulability in veno-occlusive disease following hematopoetic stem cell transplantation

BACKGROUND

Hepatic veno-occlusive disease (VOD) is one of the most disastrous complications after allogeneic hematopoetic stem cell transplantation (HSCT). Thrombocytopenia with refractoriness to platelet transfusions suggests an increased platelet consumption in these patients. Interactions between platelets and endothelial cells might contribute to the hypercoagulable state at the sinusoidal endothelium as a central mechanism in the pathogenesis of VOD.

STUDY DESIGN

The influence of activated platelets on cultured human endothelial cells was investigated in vitro. We focused on the release of plasminogen activator inhibitor-1 (PAI-1) from endothelial cells which has earlier been found to be significantly elevated in plasma of VOD patients. Endothelial cells isolated from human umbilical cords (HUVEC) were incubated with activated platelets. The release of PAI-1 in the presence or absence of specific antibodies was determined by ELISA technique. Tissue factor (TF) expression on endothelial cells was observed by flowcytometric analysis.

RESULTS

HUVEC incubated with activated platelets were found to release significantly more PAI-1 compared to untreated cultures. The endothelial PAI-1-secretion after incubation of HUVEC with activated platelets was completely inhibited by an IgG monoclonal antibody against human transforming growth factor beta-1 (TGF beta-1). In contrast, PAI-1 production was not suppressed after inhibition of HUVEC-platelet-interaction by an IgG monoclonal antibody against CD154 (CD40L) expressed on the surface of activated platelets. An increased release of PAI-1 and an increased expression of tissue factor (TF) on the endothelial cell surface were observed after stimulation with TGF beta-1.

CONCLUSION

TGF beta-1 released from activated platelets contributes to the hemostatic imbalance at the sinusoidal endothelium in patients with hepatic VOD by increase of endothelial cell PAI-1 production and TF expression. As a potent profibrotic cytokine, TGF beta-1 might further be involved in phlebosclerosis and sinusoidal fibrosis occurring in VOD.

Decreased incidence of hepatic veno-occlusive disease and fewer hemostatic derangements associated with intravenous busulfan vs oral busulfan in adults conditioned with busulfan + cyclophosphamide for allogeneic bone marrow transplantation

We investigated the occurrence of hepatic veno-occlusive disease (VOD) after allogeneic bone marrow transplantation (BMT) in 241 adults conditioned with busulfan + cyclophosphamide at a single institute and retrospectively compared 186 patients who received oral busulfan (O-Bu group) with 55 patients who received intravenous busulfan (I-Bu group). Various hemostatic parameters were determined at baseline and on days 0, 7, 14, and 21. Hepatic VOD occurred in 41.7% of the O-Bu group and in 18.5% of the I-Bu group. Multivariate analysis revealed that the I-Bu group had significantly decreased risk of VOD compared to the O-Bu group [p=0.006, odds ratio: (OR) 0.345]. Eleven patients in the O-Bu group and none of the I-Bu group developed severe VOD. A repeated measures analysis of variance (ANOVA) with a between-subjects factor revealed significant differences in post-transplant levels of antithrombin III, tissue plasminogen activator (tPA), plasminogen activator inhibitor 1 (PAI-1), and D-dimer according to the occurrence of VOD. The level of antithrombin III was significantly lower, whereas the level of D-dimer was significantly higher, in the O-Bu group than in the I-Bu group. These findings show that, in adults conditioned with busulfan + cyclophosphamide, intravenous busulfan was associated with significantly decreased incidence of VOD and fewer hemostatic derangements after allogeneic BMT compared to oral busulfan.

Veno-occlusive disease with multi-organ involvement following actinomycin-D

Actinomycin-D (Act-D) is a rare cause of veno-occlusive disease (VOD). Between 1993 and 1998, we managed 6 patients, all male, median age 19 months (range 6-48 months) who received Act-D for Wilms' tumour (n=4), clear cell sarcoma (n=1) or rhabdomyosarcoma (n=1). VOD presented with a median platelet count of 12 x 10(9)/l, INR 3.8, fibrinogen 16 mg/l, fibrinogen degradation products (FDPs) > or =80 microg/l, aspartate aminotransferase (AST) 6922 IU/l, bilirubin 47 micromol/l. In 3 cases, transient liver dysfunction and thrombocytopenia without neutropenia had been observed after a previous course of Act-D. All six children developed encephalopathy, hepatomegaly, ascites, reversed portal flow and renal impairment. All received mechanical ventilation and two required haemofiltration. The treatment was supportive. Severe Adult Respiratory Distress Syndrome developed in 3 patients, all of whom died. 3 patients recovered. The outcome of VOD with multi-organ failure is poor. Intravascular coagulopathy precedes and characterises severe VOD during Act-D treatment.