Coagulation factor XIII and markers of thrombin generation and fibrinolysis in patients with inflammatory bowel disease

The Journey Through the Pathogenesis and Treatment of Venous Thromboembolism in Inflammatory Bowel Diseases: A Narrative Review

Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders of the gastrointestinal tract including Crohn's disease and ulcerative colitis, which may result in several extraintestinal complications (∼20-30% of cases), such as increased risk of venous thromboembolism (VTE). The main pathophysiological mechanism of VTE is an inflammation-induced hypercoagulable state, and recent data have shown that endothelial dysregulation due to gut and systemic inflammation may also lead to a prothrombotic state. Several prothrombotic alterations have been described, such as the activation of the coagulation system, platelet abnormalities, and dysregulation of fibrinolysis. Furthermore, the dysregulation of the gut microbiome seems to play a vital role in increasing systemic inflammation and thus inducing a procoagulant state. Our review aims to examine the main correlations between IBD and VTE, the underlying pathophysiology, and current therapeutic options.

Balancing Microthrombosis and Inflammation via Injectable Protein Hydrogel for Inflammatory Bowel Disease

Emerging evidence indicates that a vicious cycle between inflammation and microthrombosis catalyzes the pathogenesis of inflammatory bowel disease (IBD). Over-stimulated inflammation triggers a coagulation cascade and leads to microthrombosis, which further complicates the injury through tissue hypoxia and ischemia. Herein, an injectable protein hydrogel with anti-thrombosis and anti-inflammation competency is developed to impede this cycle, cross-linked by silver ion mediated metal-ligand coordination and electronic interaction with sulfhydryl functionalized bovine serum albumin and heparin, respectively. The ex vivo experiments show that the hydrogel, HEP-Ag-BSA, exhibits excellent self-healing ability, injectability, biocompatibility, and sustained drug release. HEP-Ag-BSA also demonstrates anti-coagulation and anti-inflammation abilities via coagulation analysis and lipopolysaccharide stimulation assay. The in vivo imaging confirms the longer retention time of HEP-Ag-BSA at inflammatory sites than in normal mucosa owing to electrostatic interactions. The in vivo study applying a mouse model with colitis also reveals that HEP-Ag-BSA can robustly inhibit inflammatory microthrombosis with reduced bleeding risk. This versatile protein hydrogel platform can definitively hinder the "inflammation and microthrombosis" cycle, providing a novel integrated approach against IBD.

The impact of acquired coagulation factor XIII deficiency in traumatic bleeding and wound healing

Factor XIII (FXIII) is a protein involved in blood clot stabilisation which also plays an important role in processes including trauma, wound healing, tissue repair, pregnancy, and even bone metabolism. Following surgery, low FXIII levels have been observed in patients with peri-operative blood loss and FXIII administration in those patients was associated with reduced blood transfusions. Furthermore, in patients with low FXIII levels, FXIII supplementation reduced the incidence of post-operative complications including disturbed wound healing. Increasing awareness of potentially low FXIII levels in specific patient populations could help identify patients with acquired FXIII deficiency; although opinions and protocols vary, a cut-off for FXIII activity of ~ 60–70% may be appropriate to diagnose acquired FXIII deficiency and guide supplementation. This narrative review discusses altered FXIII levels in trauma, surgery and wound healing, diagnostic approaches to detect FXIII deficiency and clinical guidance for the treatment of acquired FXIII deficiency.

Role of Vitamin K in Intestinal Health

Intestinal diseases, such as inflammatory bowel diseases (IBDs) and colorectal cancer (CRC) generally characterized by clinical symptoms, including malabsorption, intestinal dysfunction, injury, and microbiome imbalance, as well as certain secondary intestinal disease complications, continue to be serious public health problems worldwide. The role of vitamin K (VK) on intestinal health has drawn growing interest in recent years. In addition to its role in blood coagulation and bone health, several investigations continue to explore the role of VK as an emerging novel biological compound with the potential function of improving intestinal health. This study aims to present a thorough review on the bacterial sources, intestinal absorption, uptake of VK, and VK deficiency in patients with intestinal diseases, with emphasis on the effect of VK supplementation on immunity, anti-inflammation, intestinal microbes and its metabolites, antioxidation, and coagulation, and promoting epithelial development. Besides, VK-dependent proteins (VKDPs) are another crucial mechanism for VK to exert a gastroprotection role for their functions of anti-inflammation, immunomodulation, and anti-tumorigenesis. In summary, published studies preliminarily show that VK presents a beneficial effect on intestinal health and may be used as a therapeutic drug to prevent/treat intestinal diseases, but the specific mechanism of VK in intestinal health has yet to be elucidated.

Elevated plasma D-dimer levels are associated with risk of future incident venous thromboembolism

BACKGROUND

D-dimer, a global biomarker for activation of the coagulation and fibrinolysis systems, is useful in assessing individual risk of venous thromboembolism (VTE) recurrence. However, there is limited information on the association between D-dimer and risk of a first lifetime VTE event.

OBJECTIVES

To investigate the association between plasma D-dimer levels and risk of future incident VTE.

METHODS

A population-based nested case-control study, comprising 414 VTE patients and 843 randomly selected age- and sex-matched controls, was derived from the Tromsø Study (1994-2007). D-dimer was measured in plasma samples collected at cohort baseline (1994-95). Odds ratios (ORs) for VTE with 95% confidence intervals (CIs) were estimated according to quartile cut-offs of D-dimer levels determined in controls.

RESULTS

The risk of VTE increased across quartiles of D-dimer levels (P_trend = 0.014) in the age- and sex-adjusted model. Participants with plasma D-dimer levels in the highest quartile (≥152 ng/mL) had an OR for VTE of 1.65 (95% CI 1.14-2.40) compared with those in the lowest quartile (<94 ng/mL). The ORs were marginally attenuated after additional adjustment for body mass index (BMI) (OR 1.51, 95% CI 1.04-2.20) and C-reactive protein (CRP) (OR 1.34, 95% CI 0.90-1.98). Similar results were obtained for VTE subgroups, i.e. deep vein thrombosis, pulmonary embolism, and provoked/unprovoked events.

CONCLUSION

Our results indicate that elevated plasma D-dimer levels are associated with increased risk of incident VTE. However, the attenuation of risk estimates upon additional adjustment for BMI and CRP suggests that D-dimer partly reflects underlying conditions associated with obesity and an inflammatory state.

Shedding Light on Hemostasis in Patients With Inflammatory Bowel Diseases

Patients with inflammatory bowel diseases (IBD) have an increased risk of thrombosis, possibly due to changes in blood cells and molecules involved in hemostasis. They have increased platelet counts and reactivity as well as increased platelet-derived large extracellular vesicles. Coagulation is continuously activated in patients with IBD, based on measured markers of thrombin generation, and the anticoagulant functions of endothelial cells are damaged. Furthermore, fibrinogen is increased and fibrin clots are denser. However, pathogenesis of thrombosis in patients with IBD appears to differ from that of patients without IBD. Patients with IBD also take drugs that might contribute to risk of thrombosis, complicating the picture. We review the features of homeostasis that are altered in patients with IBD and possible mechanisms of this relationship.

Inflammatory Bowel Disease and Acute Coronary Syndromes: From Pathogenesis to the Fine Line Between Bleeding and Ischemic Risk

Inflammatory bowel disease (IBD) is a pathological condition that first involves the gastrointestinal wall but can also trigger a systemic inflammatory state and thus extraintestinal manifestations. Systemic inflammation is probably secondary to the passage of bacterial products into the bloodstream because of altered intestinal permeability and the consequent release of proinflammatory mediators. Inflammation, through several diverse pathophysiological pathways, determines both a procoagulative state and systemic endothelial dysfunction, which are both deemed to be responsible for venous and arterial thromboembolic adverse events. The management of systemic thrombotic complications is particularly challenging in this category of patients, who also present a high bleeding risk; what is more, both bleeding and thrombotic risks peak during the active phases of the disease. The literature suggests that treating physicians have been, so far, more heavily influenced by concerns about bleeding than by the thrombotic risk. Despite the absence of data provided by large cohorts or randomized studies, the high risk of arterial and venous atherothrombosis in patients with IBD seems unquestionable. Moreover, several reports suggest that when arterial thromboembolism involves the coronary vessels, causing acute coronary syndromes, ischemic complications from antithrombotic drug undertreatment are frequent and severe. This review aims to shed light on the tricky balance between the ischemic and hemorrhagic risks of patients with IBD and to highlight how difficult it is for clinicians to define a tailored therapy based on a case-by-case, careful, and unprejudiced clinical evaluation.

Laboratory Assessment of Disease Activity in Pediatric Patients with Inflammatory Bowel Disease: What’s New?

Laboratory tests are an integral part of both the diagnostic and follow-up algorithm of patients with inflammatory bowel disease (IBD). Their advantages over other non-invasive methods for assessing disease activity are greater objectivity than clinical activity indices and imaging studies. This review aims to analyze shortly the most common laboratory tests used to assess disease activity in pediatric patients with IBD. In addition to the conventional blood and serum markers that are not specific for gut inflammation, although routinely used, we also reviewed the established fecal markers such as calprotectin, lactoferrin, M2-pyruvate kinase, osteoprotegerin, HMGB1, chitinase 3-like 1, and the promising non-coding microRNA. In conclusion, neither marker is unique to the pediatric IBD. More clinical data are required to assess biomarkers’ full potential for diagnosis, management, and follow-up of pediatric IBD patients.

Henoch-Schönlein purpura in Saudi Arabia: characteristics and rare vital organ involvement

Henoch-Schönlein purpura (HSP) is the most common small vessel vasculitis in children with an annual incidence of between 10 and 30 per 100,000. It is an inflammation that affects many organs primarily in the skin, gastrointestinal (GI) tract, musculoskeletal, also vital organs like kidneys and lungs which may lead to chronic kidney disease and pulmonary hemorrhage. In this review, we are showing the characteristics of Saudi patients with HSP and the relation with preceding infections, gender, and seasonal variations in addition to the common and most severe systemic involvements. We found cases that were challenging to diagnose and others with unfortunate fetal complications.

Acquired factor XIII deficiency: A review

Acquired factor XIII (FXIII) deficiency is a rare bleeding disorder that can manifest with spontaneous or delayed life-threatening hemorrhage. Causes of acquired deficiency include immune-mediated inhibition, as well as non-immune FXIII hyperconsumption or hyposynthesis. The occurrence of acquired FXIII deficiency can be idiopathic or may be associated with comorbidities, such as malignancies or autoimmune disorders. Recognition of acquired FXIII deficiency and its underlying cause is imperative, as treatment options vary depending on the etiology. Diagnosis requires quantitative FXIII testing in addition to supplemental inhibitor studies if the clinical situation suggests an immune-mediated pathophysiology. Treatment may involve FXIII replacement, antifibrinolytic administration, and/or inhibitor eradication. However, treatment targets and thresholds are undefined in acquired FXIII deficiency. This review will focus on the clinical characteristics, diagnostic issues and therapeutic options for both immune and non-immune acquired FXIII deficiency. Cases are described to illustrate the clinical features of acquired FXIII deficiency.

Systemic and intestinal levels of factor XIII-A: the impact of inflammation on expression in macrophage subtypes

BACKGROUND

Subunit A of coagulation factor XIII (FXIII-A) is important for clot stability and acts in the subsequent wound healing process. Loss of plasma FXIII-A has been reported after surgery, sepsis, and inflammatory conditions. In the intestinal mucosa, FXIII-A is expressed by macrophages and cellular FXIII-A has been associated with phagocytosis and migration of macrophages. The objective was to evaluate the consequences of intestinal inflammation on resident mucosal macrophages, focusing on the level and distribution of FXIII-A.

METHODS

Plasma and colonic biopsies were collected from 67 patients with ulcerative colitis and controls. Intestinal samples were stained using immunohistochemistry for FXIII-A and macrophages (CD68, CD163 and iNOS). In situ hybridization were used to assess the intestinal expression of FXIII-A. FXIII-A antigen and activity levels were measured in plasma.

RESULTS

Increased infiltration of CD68 positive macrophages in the inflamed mucosa coincided with increased extracellular deposited FXIII-A and decreased expression and intracellular protein levels of FXIII-A. A decreased proportion of FXIII-A/CD68/CD163 triple-positive macrophages was observed in inflamed mucosa, indicating a reduction of the M2 phenotype with consequent loss of FXIII-A. No induction of iNOS positive macrophages was observed. Stimulation of naïve monocytes with physiological concentrations of pro-inflammatory mediators negatively affected the expression of FXIII-A. Measurements in plasma confirmed the loss of both FXIII antigen and activity during active disease.

CONCLUSIONS

Intestinal inflammation in UC induces loss of M2 macrophages with subsequent loss of FXIII-A synthesis. The loss of cellular FXIII-A may impact migration and phagocytosis, and hence limit pathogen eradication in UC.

Platelet Activation Markers Are Associated with Crohn's Disease Activity in Patients with Low C-Reactive Protein

BACKGROUND

In assessing Crohn's disease (CD) activity, C-reactive protein (CRP) is an important indicator of inflammation; however, it is not necessarily associated with the Crohn's Disease Activity Index (CDAI), particularly in patients with low CRP. Recently, platelet activation factors have been recognized due to their importance in the inflammatory response. In this study, we examined associations between the CDAI and platelet factor 4 (PF-4), β-thromboglobulin (β-TG), and other coagulation and fibrinolysis factors.

AIMS

We aimed to find a new marker for evaluating disease activity in patients with CD and low CRP.

METHODS

Nine markers, including CRP, platelet count, white blood cell count, fibrin and fibrinogen degradation product, fibrinogen, thrombin-antithrombin complex, prothrombin fragments 1 + 2, PF-4, and β-TG were evaluated in 47 patients with CD and low CRP (<1.0 mg/dl). Patients were assigned to high or low disease activity groups, CDAI-H (CDAI ≥ 150) and CDAI-L (CDAI < 150), respectively.

RESULTS

CDAI-H exhibited significantly higher PF-4 and β-TG levels than CDAI-L (P < 0.01). Other markers were not significantly different between groups. CDAI was positively correlated with the levels of PF-4 and β-TG (P = 0.0033 and 0.0024; r = 0.4202 and 0.4321, respectively). Receiver operating characteristic curve analyses of PF-4 and β-TG showed high sensitivity (61.9 and 81%, respectively) and specificity (84.7 and 69.2%, respectively) for diagnosing active CD.

CONCLUSION

Among eight potential markers, PF-4 and β-TG were the most highly correlated with CDAI in patients with CD and low CRP. PF-4 and β-TG levels showed promise as new markers for assessing CD in patients with low CRP.

Successful treatment of severe gastrointestinal manifestations of Henoch-Schonlein Purpura and factor XIII deficiency using cryoprecipitate transfusion

Henoch–Schonlein Purpura (HSP) might present with severe gastrointestinal (GI) involvement. Herein, we report 3 cases of HSP with severe GI manifestations in the form of hematemesis, melena, pancreatitis, and erosive gastritis. Different treatment modalities were not successful. Low factor XIII levels were found in all patients and Cryoprecipitate transfusion resulted in significant immediate clinical improvement.

Thrombosis in inflammatory bowel diseases: what's the link?

Inflammatory bowel disease affects more than 2 million people in Europe, with almost 20% of patients being diagnosed in pediatric age. Patients with inflammatory bowel disease are at increased risk of thromboembolic complications which may affect patients’ morbidity and mortality. The risk of the most common thromboembolic events, such as deep venous thrombosis and pulmonary embolism, are estimated to be three-fold increased compared to controls, but many other districts can be affected. Moreover, patients with ulcerative colitis and Crohn’s disease experience thromboembolic events at a younger age compared to general population. Many factors have been investigated as determinants of the pro-thrombotic tendency such as acquired risk factors or genetic and immune abnormalities, but a unique cause has not been found. Many efforts have been focused on the study of abnormalities in the coagulation cascade, its natural inhibitors and the fibrinolytic system components and both quantitative and qualitative alterations have been demonstrated. Recently the role of platelets and microvascular endothelium has been reviewed, as the possible link between the inflammatory and hemostatic process.

Inflammatory bowel disease and thromboembolism

Patients with inflammatory bowel disease (IBD) have an increased risk of vascular complications. Thromboembolic complications, both venous and arterial, are serious extraintestinal manifestations complicating the course of IBD and can lead to significant morbidity and mortality. Patients with IBD are more prone to thromboembolic complications and IBD per se is a risk factor for thromboembolic disease. Data suggest that thrombosis is a specific feature of IBD that can be involved in both the occurrence of thromboembolic events and the pathogenesis of the disease. The exact etiology for this special association between IBD and thromboembolism is as yet unknown, but it is thought that multiple acquired and inherited factors are interacting and producing the increased tendency for thrombosis in the local intestinal microvasculature, as well as in the systemic circulation. Clinicians' awareness of the risks, and their ability to promptly diagnose and manage tromboembolic complications are of vital importance. In this review we discuss how thromboembolic disease is related to IBD, specifically focusing on: (1) the epidemiology and clinical features of thromboembolic complications in IBD; (2) the pathophysiology of thrombosis in IBD; and (3) strategies for the prevention and management of thromboembolic complications in IBD patients.

Inflammatory bowel disease: epidemiology, pathology and risk factors for hypercoagulability

Hypercoagulability observed in patients with inflammatory bowel diseases (IBD) may lead to thromboembolic events (TE), which affect the venous and arterial systems alike and are an important factor in patients' morbidity and mortality. The risk of TE in IBD patients has been demonstrated to be approximately three-fold higher as compared to the general population. The pathogenesis of thrombosis in IBD patients is multifactorial and not fully explained. The most commonly listed factors include genetic and immune abnormalities, disequilibrium between procoagulant and anticoagulant factors, although recently, the role of endothelial damage as an IBD-triggering factor is underlined. Several studies report that the levels of some coagulation enzymes, including fibrinogen, factors V, VII, VIII, active factor XI, tissue factor, prothrombin fragment 1 + 2 and the thrombin-antithrombin complex, are altered in IBD patients. It has been demonstrated that there is a significant decrease of tissue plasminogen activator level, a marked increase of plasminogen activator inhibitor type 1 and thrombin-activable fibrinolysis inhibitor, a significantly lower level of antithrombin III and tissue factor pathway inhibitor. IBD patients have been also observed to produce an increased amount of various anticoagulant antibodies. Hyperhomocysteinemia, which is a potential risk factor for TE was also observed in some IBD patients. Further studies are necessary to assess the role of coagulation abnormalities in IBD etiology and to determine indications for thromboprophylactic treatment in patients at high risk of developing TE.

Tissue-regenerating functions of coagulation factor XIII

The protransglutaminase factor XIII (FXIII) has recently attracted attention within the field of tissue regeneration, as it has been found that FXIII significantly influences wound healing by exerting a multitude of functions. It supports hemostasis by enhancing platelet adhesion to damaged endothelium, and by its cross-linking activity it stabilizes the formed fibrin clot. Furthermore, FXIII limits bacterial dissemination from the wound and incorporates macromolecules of importance for cellular infiltration, supporting cell migration and survival. FXIII-mediated complex formation of the vascular endothelial growth factor receptor 2 and αV β3 integrin is important for angiogenesis, supporting the formation of granulation tissue. Chronic inflammatory conditions involving bleeding and activation of the coagulation cascade have been shown to lead to reduced FXIII levels in plasma. Of particular importance for this review is the fact that patients suffering from inflammatory bowel disease (IBD) have reduced FXIII antigen levels and activity. Furthermore, these patients show impaired mucosal healing, which supports the inflammatory state of the disease. This review summarizes the role of FXIII in the healing of wounds, and briefly summarizes the previous use of FXIII in clinical settings. Moreover, it addresses the potential role for FXIII as a therapeutic agent in the healing of persistent wounds during chronic conditions, with an emphasis on IBD.

New developments in the area of factor XIII

Coagulation factor (F)XIII is best known for its role in fibrin stabilization and cross-linking of antifibrinolytic proteins to the fibrin clot. From patients with congenital FXIII deficiency, it is known that FXIII also has important functions in wound healing and maintaining pregnancy. Over the last decade more and more research groups with different backgrounds have studied FXIII and have unveiled putative novel functions for FXIII. FXIII, with its unique role as a transglutaminase among the other serine protease coagulation factors, is now recognized as a multifunctional protein involved in regulatory mechanisms and construction and repair processes beyond hemostasis with possible implications in many areas of medicine. The aim of this review was to give an overview of exciting novel findings and to highlight the remarkable diversity of functions attributed to FXIII. Of course, more research into the underlying mechanisms and (patho-)physiological relevance of the many described functions of FXIII is needed. It will be exciting to observe future developments in this area and to see if and how these interesting findings may be translated into clinical practice in the future.

Novel treatment for congenital FXIII deficiency

Congenital Factor XIII (FXIII) deficiency is a rare autosomal recessive inherited disease leading to severe bleeding diathesis. In this issue of Blood, Inbal and colleagues report on a safe and novel treatment of this rare disorder with recombinant FXIII (rFXIII).1

Continuous active state of coagulation system in patients with nonthrombotic inflammatory bowel disease

This study was planned for searching possible changes of the total coagulation and fibrinolysis system in inflammatory bowel disease (IBD) in order to obtain some clues for explaining the relation between IBD and hypercoagulability. A total of 24 patients with ulcerative colitis, 12 patients with Crohn disease, and 20 healthy controls were studied. Platelets; prothrombin time (PT); partial thromboplastin time (PTT); fibrinogen; D-dimer; fibrinogen degradation products; protein C; protein S; antithrombin; thrombin time; von Willebrand factor; coagulation factors V, VII, VIII, IX, XI, and XIII; plasminogen; antiplasmin; tissue plasminogen activator; plasminogen activator inhibitor 1; and prothrombin fragments 1 + 2 were studied. Most of the procoagulants (platelets, fibrinogen, von Willebrand factor, coagulation factor IX, and plasminogen activator inhibitor 1) were found increased together with decreases in some anticoagulants (protein S and antithrombin) in IBD. Also the activation markers of coagulation (D-dimer, fibrinogen degradation products, and prothrombin fragments 1 + 2) were all increased. The parameters of the total coagulation-fibrinolysis system were increased in IBD, regardless of the form and the activity of the disease.

Induction of apoptosis by thrombin in the cultured neurons of dorsal motor nucleus of the vagus

BACKGROUND

A previous study demonstrated the presence of protease-activated receptor (PAR) 1 and 2 in the dorsal motor nucleus of vagus (DMV). The aim of this study is to characterize the effect of thrombin on the apoptosis of DMV neurons.

METHODS

The dorsal motor nucleus of vagus neurons were isolated from neonatal rat brainstems using micro-dissection and enzymatic digestion and cultured. Apoptosis of DMV neurons were examined in cultured neurons. Apoptotic neuron was examined by TUNEL and ELISA. Data were analyzed using anova and Student's t-test.

KEY RESULTS

Exposure of cultured DMV neurons to thrombin (0.1 to 10 U mL(-1)) for 24 h significantly increased apoptosis. Pretreatment of DMV neurons with hirudin attenuated the apoptotic effect of thrombin. Similar induction of apoptosis was observed for the PAR1 receptor agonist SFLLR, but not for the PAR3 agonist TFRGAP, nor for the PAR4 agonist YAPGKF. Protease-activated receptors 1 receptor antagonist Mpr(Cha) abolished the apoptotic effect of thrombin, while YPGKF, a specific antagonist for PAR4, demonstrated no effect. After administration of thrombin, phosphorylation of JNK and P38 occurred as early as 15 min, and remained elevated for up to 45 min. Pretreatment of DMV neurons with SP600125, a specific inhibitor for JNK, or SB203580, a specific inhibitor for P38, significantly inhibited apoptosis induced by thrombin.

CONCLUSIONS & INFERENCES

Thrombin induces apoptosis in DMV neurons through a mechanism involving the JNK and P38 signaling pathways.

Haemostatic system in inflammatory bowel diseases: New players in gut inflammation

Inflammation and coagulation constantly influence each other and are constantly in balance. Emerging evidence supports this statement in acute inflammatory diseases, such as sepsis, but it also seems to be very important in chronic inflammatory settings, such as inflammatory bowel disease (IBD). Patients with Crohn’s disease and ulcerative colitis have an increased risk of thromboembolic events, and several abnormalities concerning coagulation components occur in the endothelial cells of intestinal vessels, where most severe inflammatory abnormalities occur. The aims of this review are to update and classify the type of coagulation system abnormalities in IBD, and analyze the strict and delicate balance between coagulation and inflammation at the mucosal level. Recent studies on possible therapeutic applications arising from investigations on coagulation abnormalities associated with IBD pathogenesis will also be briefly presented and critically reviewed.

Thrombophilic Risk Factors in Patients With Inflammatory Bowel Disease

Background

Inflammatory bowel disease (IBD) patients have an increased risk for thromboembolism. The aim of this study was to assess the presence of thrombophilic risk factors in IBD patients and to assess the associations of these factors with disease activity.

Methods

Forty-eight patients with IBD (24 ulcerative colitis, 24 Crohn’s disease) and 40 matched healthy control individuals were enrolled. In addition to routine biochemical analysis, fasting blood samples were studied for prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, protein-C, protein-S, antithrombin III, factor VII, factor VIII, D-dimer, vitamin B₁₂, folic acid and homocysteine.

Results

Levels of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fibrinogen, D-dimer and the number of platelets were significantly higher in patients with IBD. When compared to control group, in patients with Crohn’s disease serum homocystein levels were significantly higher (p = 0.025) while serum folic acid levels were significantly lower (p < 0.019). Levels of fibrinogen, D-dimer, protein C, factor VIII, total homocystein and the number of platelets were found to be significantly higher in Crohn’s disease patients who were in active period of the disease.

Conclusions

Thrombophilic defects are multifactorial and might be frequently seen in IBD patients. They might contribute to thrombotic complications of this disease.

Assessment of thrombophilic abnormalities during the active state of inflammatory bowel disease

BACKGROUND/AIMS

Thromboembolic disease has been recognized as a complication of inflammatory bowel disease (IBD). The relative contributions of inherited or acquired thrombophilia and the inflammatory response to the mechanism of this tendency are unclear. Thrombotic events are more common in active disease although significant numbers also occur spontaneously. The aim of this study was to investigate common thrombophilic markers in patients with active IBD.

METHODS

Twenty-six patients with IBD who had active disease, and 40 sex- and age-matched non-IBD patients were recruited into the study. For all the subjects, complete blood counts, C-reactive protein levels, erythrocyte sedimentation rate, International normalized ratio, activated partial thromboplastin time, and levels of lupus anticoagulant, anticardiolipin antibodies (ACA IgG), proteins C and S, antithrombin-III (AT-III), and factor V were measured.

RESULTS

The International normalized ratio, activated partial thromboplastin time, and levels of proteins C and S were comparable between the two groups. However, antithrombin-III levels were significantly lower in the IBD group as compared with that in the healthy control group (P < 0.001). ACA IgG was detected in one patient in the IBD group. Factor V Leiden mutation was present in 3.8% of the patients in the IBD group, whereas the prevalence was 2.5% in the control group. Significantly elevated platelet counts were observed in patients with active Crohn's disease compared with that in the control group (P < 0.001), but they were not significantly increased in active ulcerative colitis (P = 0.231).

CONCLUSIONS

The present study failed to establish a strong association between the common thrombophilic markers and the active clinical course of IBD, with the exception of high platelet counts and lower levels of AT-III in the IBD group as compared with those in the control group. All other parameters of thrombophilia were comparable between the two groups.

PAI-1 and TAFI in inflammatory bowel disease: the yin and yang of the fibrinolytic system

In both Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD), an increased risk of thrombotic events has been demonstrated. Pathogenesis of thrombosis is multifactorial as various primary coagulation system abnormalities other than acquired factors have been reported. The fibrinolytic system has been widely investigated in IBD. Most of the available data report an imbalance in fibrinolytic capacity with a tendency toward a hypofibrinolytic state. Plasma thrombin-activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 are fundamental inhibitors of the fibrinolytic process and are also considered to be acute-phase reactants. Recent studies have shown an imbalance of plasminogen activator inhibitor-1 and thrombin-activatable fibrinolysis inhibitor, suggesting that these molecules might contribute to thromboembolic events in both forms of IBD.

Biomarkers of altered coagulation and fibrinolysis as measures of disease activity in active inflammatory bowel disease: a gender-stratified, cohort analysis

BACKGROUND

Growing evidence recognizes inflammatory bowel disease (IBD) as a chronic inflammatory condition characterized by a hypercoagulable state and prothrombotic conditions. The aims of our study were to evaluate the abnormalities in coagulation and fibrinolysis status in patients with IBD, and to analyze parameters of altered coagulation and fibrinolysis status which can correlated with and predict inflammatory parameters of disease activity.

METHODS

A cohort of 271 consecutive IBD patients was compared with healthy controls for coagulation and fibrinolysis status. Associations between altered coagulation and fibrinolysis status stratified by gender and inflammatory parameters were analyzed.

RESULTS

The mean levels of platelet, platelet distribution width, prothrombin time, fibrinogen, activated partial thromboplastin time were significantly higher in IBD patients than in healthy controls (all P<0.05). Mean platelet volume was lower in male patients with IBD than in healthy controls (P<0.01). Furthermore, multiple linear regression indicated that fibrinogen was an independent predictor of ESR (beta=1.316, P=<0.001) and CRP (beta=1.233, P=0.015) in male patients with active ulcerative colitis. Platelet (beta=0.436, P=0.037) and prothrombin time (beta=0.810, P=<0.001) were predictors of Crohn's Disease Activity Index in female patients with Crohn's disease.

CONCLUSIONS

To our knowledge, this study provides characteristics on altered coagulation and fibrinolysis status in active IBD patients using the largest number of cases assembled in one study to date. Our data suggest that in IBD patients, abnormalities in coagulation and fibrinolysis status were associated with disease activity. Fibrinogen, platelet and prothrombin time were predictors of inflammation.

The microvascular thrombi of colonic tissue in ulcerative colitis

Mucosal microvascular thrombi in rectal biopsies were observed in some ulcerative colitis (UC). Heparin may be effective in steroid resistant UC in some studies, however, the new results of meta-analysis demonstrated a non-significant effect of heparin in controlled clinical trials, differing markedly from observational studies. The objective of this study was to identify colonic microvascular thrombi in larger cases with UC, and analyse its possible risk factors: age, gender, histologic score, extent of lesions and operation or biopsy specimens, and assess the significance of microvascular thrombosis in patients with UC. The microvascular thrombi were identified by immunohistochemical staining with anti-CD61 monoclonal antibody and Martius scarlet blue (MSB) staining in 40 colonic tissue samples of UC (31 biopsy specimens and nine operated cases) and 12 cases of normal colon tissue from operated colonic carcinoma. Logistic regression analysis was used to assess the relationship of age, gender, degree of histology, origin of the specimens, extent of lesions and microvascular thrombi examined. Microvascular thrombi were positive in 14 of 40 UC cases, and none in the controls. The presence of microvascular thrombi was related to operation specimens with odds ratio 11.667, P=0.0179, it might be also related to histologic score (OR=1.350) and extent of lesions (OR=1.619). These results suggest that microvascular thrombosis may be one of the important pathogenesis in some UC, and that the effect of anticoagulant treatment still needs to be assessed.

Mutations in clotting factors and inflammatory bowel disease

BACKGROUND

Patients with Crohn's disease (CD) and ulcerative colitis (UC) have a three- to fourfold greater risk of venous thrombosis compared with the general population. We aimed to determine if patients with CD and UC had a greater likelihood of mutations in genes that increase clotting risk, in a population-based case-control study.

METHODS

Subjects were drawn from the University of Manitoba IBD Research Registry and controls were drawn from Manitoba Health's administrative database. Cases (CD, N = 327; UC, N = 165) and controls (N = 412) underwent venipuncture. DNA was purified from whole blood. Genotypes for wild-type and common mutations that have been associated with venous thrombosis for each of Factor II (prothrombin) (G20210A), Factor V (G1691A:'Leiden'), methylenetetrahydrofolate reductase (MTHFR, C677T), and Factor XIII (val34leu) were assessed.

RESULTS

A total of 1.5% and 6.1% were heterozygous for Factor II and Factor V variants, respectively, without differences among cases and controls. Only one subject was homozygous for Factor V Leiden (and none were homozygous for Factor II mutation). Although some differences were observed among cases and controls in the prevalence of MTHFR C677T (decrease in mutant allele carriership in UC) and FXIII val34leu (increase in double mutant allele carriership in CD), these did not explain an excess risk of thrombosis. Age, sex, or disease phenotypes were not associated with prothrombotic genotypes.

CONCLUSIONS

While there was a slightly greater prevalence of Factor XIII mutation carriership in CD, we did not find that gene mutations for these four common factors could explain the greater risk of venous thrombosis in CD and UC.

Activations of coagulation and fibrinolysis secondary to bowel inflammation in patients with ulcerative colitis

BACKGROUND

Recent investigations suggest that activation of coagulation and fibrinolysis occurs in patients with ulcerative colitis (UC). However, the role of the hypercoagulable state in UC has not been determined. On the other hand, there are no reports dealing with coagulation in ischemic colitis (IC), in which acute bowel inflammation and reversible vascular occlusion affect the colon. Thus, our aim was to evaluate the hyper states of coagulation and fibrinolysis in UC by comparing activations of coagulation and fibrinolysis in patients with active UC and in those with IC.

METHODS

Twenty-four patients with active UC and 12 patients with IC were studied, with 18 patients with inactive UC serving as controls. We investigated the activation of the coagulation system, including platelet counts, activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time (PT), serum concentrations of von Willebrand factor (vWF), activated factors XII, XI, X, IX, VIII, VII, V, II, fibrinogen, prothrombin fragments 1+2 (F1+2), thrombin-antithrombin complexes (TAT), protein S, protein C, plasminogen, alpha-2 plasminogen inhibitor (alpha-2PI) and D-dimer (D-D).

RESULTS

Median serum vWF concentrations, F1+2, TAT, fibrinogen, activated factor XI, IX, VIII and V were significantly elevated in patients with active UC and IC compared to those in patients with inactive UC. There was no significant difference between active UC and IC patients in the mean values of any of the factors that were measured.

CONCLUSION

The results of the present study indicate that the coagulation-fibrinolysis system is activated in patients with active bowel inflammation such as active UC and IC, and that the hyper states of coagulation and fibrinolysis in patients with active UC are secondary to bowel inflammation.

Inflammation and coagulation in inflammatory bowel disease: The clot thickens

Inflammation and coagulation play crucial roles in the pathogenesis of multiple chronic inflammatory disorders. Growing evidence highlights a tight mutual network in which inflammation, coagulation, and fibrinolysis play closely related roles. Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel disease (IBD), are chronic inflammatory conditions, characterized by a hypercoagulable state and prothrombotic conditions, and accompanied by abnormalities in coagulation. From a pathophysiological point of view, cells and molecules classically implicated in the physiological process of coagulation have now been shown to behave abnormally in IBD and possibly to also play an active role in disease pathogenesis and/or disease progression. This paper reviews studies performed on the coagulation profile and risk factors for thrombosis in IBD. In particular, an overview is provided of the epidemiology, clinical features, and etiology of thromboembolic complications in IBD. Furthermore, we review hemostatic abnormalities in IBD, as well as the cell types involved in such processes. Finally, we highlight the coagulation system as a dynamic participant in the multifaceted process of chronic intestinal inflammation. Overall, an overview is provided that the coagulation system represents an important, though previously underestimated, component of IBD pathogenesis, and may be a possible target for therapeutic intervention.

Low-molecular-weight heparin (enoxaparin) as adjuvant therapy in the treatment of active ulcerative colitis: a randomized, controlled, comparative study

BACKGROUND

Heparin could be beneficial to the treatment of active ulcerative colitis because of its anticoagulant, anti-inflammatory and immunomodulatory properties.

AIM

To evaluate the tolerability, safety and efficacy of low-molecular-weight heparin as adjuvant therapy in patients with active ulcerative colitis.

METHODS

Thirty-four adult patients with active ulcerative colitis were consecutively included in a prospective, randomized, comparative study, and were treated for 12 weeks. Eighteen patients in the 'standard therapy' group were treated with aminosalicylates and weekly tapered corticosteroids. Sixteen patients in the 'heparin therapy' group were treated with standard therapy plus enoxaparin 100 Anti-Xa IU/kg/day subcutaneously.

RESULTS

Seventeen patients in the 'standard therapy' group and 15 patients in the 'heparin therapy' group completed the study. Tolerability and compliance to therapy were excellent and no withdrawals were noted because of complications. There was a significant improvement in the disease severity in both groups (P<0.001), without any difference between them (P=not significant). Both treatment groups showed similar proportions of disease improvement (65% and 73%, respectively; P=not significant). There were no significant differences in inflammation (fibrinogen, ESR, CRP) and coagulation (thrombin-antithrombin complex, F1+2, D-dimers) parameters during and at the end of the study between treatment groups.

CONCLUSION

Adjuvant administration of low-molecular heparin in patients with active ulcerative colitis is safe and well tolerated, but no additive benefit over standard therapy for ulcerative colitis was noted.

Thrombosis and inflammatory bowel disease

Interaction between thrombosis and inflammation is increasingly recognized. With this, interest has arisen in the role of thrombosis in inflammatory conditions, including the inflammatory bowel diseases. Although the association between active inflammatory bowel disease and thromboembolic complications has long been known, there has been a resurgence in research into the role of thrombosis and the hemostatic system in the pathogenesis of both ulcerative colitis and Crohn's disease. Here we review the increased frequency of thromboembolic complications occurring in patients with inflammatory bowel disease; whether thrombosis might play a part in the initiation and maintenance of inflammation in inflammatory bowel disease; abnormalities of the coagulation system found in patients with inflammatory bowel disease; platelet dysfunction in inflammatory bowel disease; the mechanisms by which hemostatic processes might be proinflammatory in inflammatory bowel disease; and how these interactions might impact not only on the prevention of complications, but also on the treatment of the underlying inflammation in inflammatory bowel disease.

Safety, pharmacokinetics, and immunogenicity of single-dose rFXIII administration to healthy volunteers

BACKGROUND

Factor XIII (FXIII) is a transglutaminase that cross-links fibrin and other proteins to improve clot strength and resistance to fibrinolysis. Both congenital and acquired FXIII deficiency may result in a bleeding diathesis, and plasma-derived FXIII has been used to treat many of these clinical conditions.

OBJECTIVES

A clinical study was designed and performed to evaluate the safety, pharmacokinetics, and immunogenicity of recombinant FXIII (rFXIII) administration to healthy adult volunteers.

PATIENTS AND METHOD

Fifty healthy adult volunteers were enrolled in this randomized, double-blinded, placebo-controlled study. A single dose of rFXIII, ranging from 2 U kg(-1) to 50 U kg(-1), or placebo was administered. Safety was evaluated by capturing adverse events, clinical safety laboratory studies, and clinical score for deep venous thrombosis. Blood samples were taken for pharmacokinetic and immunogenicity analysis throughout the 28-day follow-up period.

RESULTS

Recombinant FXIII was well tolerated, with no serious adverse events or dose-related toxicities. Following a single i.v. injection of 50 U kg(-1) rFXIII, the estimated terminal half-life was 270-320 h, the volume of distribution ranged from 40 to 75 mL kg(-1), and FXIII activity increased 1.77% per 1 U kg(-1) rFXIII administered. Increase in circulating A2B2 and decrease in free FXIII-B subunit indicate in vivo formation of FXIII heterotetramer. An immunogenic response to rFXIII or yeast, the production host, was not observed.

CONCLUSIONS

Recombinant FXIII was well tolerated at doses of up to 50 U kg(-1) in healthy adult volunteers. The safety, pharmacological and immunological profile of rFXIII suggests it should be studied in patients with congenital FXIII deficiency as well as evaluated as a systemic hemostat in patients with acquired FXIII deficiency or hemorrhage.

Association between enhanced soluble CD40 ligand and prothrombotic state in inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease is associated with an increased incidence of thromboembolic complications. The aim of this study was to investigate the role of the soluble CD40 ligand (sCD40L), which displays prothrombotic properties, in patients with ulcerative colitis (UC) and Crohn's disease (CD) in comparison with inflammatory and healthy controls.

METHODS

Plasma levels of sCD40L, prothrombin fragment 1+2 (F1+2), thrombin-antithrombin (TAT) complex and soluble P-selectin were measured in 104 inflammatory bowel disease patients (54 ulcerative colitis and 50 Crohn's disease), in 18 cases with other causes of intestinal inflammation and in 80 healthy controls using commercially available enzyme-linked immunosorbent assays. Plasma levels of sCD40L were correlated with disease activity, type, localization and treatment as well as with the measured thrombophilic parameters.

RESULTS

CD patients had significantly higher sCD40L levels than both groups of controls (CD vs HC P < 0.001; CD vs non-IBD P < 0.05). UC patients had higher but not significantly different sCD40L levels compared with the controls. Both UC and CD patients with active disease had significantly higher sCD40L levels in comparison with patients with inactive disease. Plasma levels of sCD40L were correlated with platelet count (r = 0.27, P = 0.001). They also showed a correlation with prothrombin F1+2 (r = 0.16, r = 0.03) and TAT (r = 0.15, r = 0.04) as well as with P-selectin (r = 0.19, P = 0.01).

CONCLUSIONS

The increased sCD40L plasma levels may represent, at least in some degree, a molecular link between inflammatory bowel disease and the procoagualant state.

Platelets trigger a CD40-dependent inflammatory response in the microvasculature of inflammatory bowel disease patients

BACKGROUND & AIMS

Platelets circulate in an activated state in patients with inflammatory bowel disease (IBD), but their role in the pathogenesis of IBD is unclear. The recent demonstration that activated platelets express CD40 ligand (L) provides a mechanism of interaction with CD40-positive endothelial cells, inducing them to produce proinflammatory mediators. We investigated whether platelets from patients with IBD express enhanced levels of CD40L and induce human intestinal microvascular endothelial cells (HIMEC) to up-regulate cell adhesion molecule (CAM) expression and secrete chemokines.

METHODS

CD40L expression was assessed in resting and thrombin-activated platelets by flow cytometry and in mucosal microthrombi by confocal microscopy. Platelet-HIMEC cocultures were used to study CAM up-regulation, and interleukin (IL)-8 and RANTES production by HIMEC.

RESULTS

IBD platelets expressed significantly higher CD40L levels than those of healthy subjects, and CD40L-positive platelets were detected in IBD-involved mucosa. Activated platelets up-regulated expression of intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 as well as production of interleukin 8 by HIMEC in a CD40-dependent fashion. High levels of RANTES were present in platelet-HIMEC cocultures and platelets were identified as the source of this chemokine, which mediated T-cell adhesion to HIMEC.

CONCLUSIONS

These results show that platelets can actively contribute to mucosal inflammation and represent a previously unrecognized component of IBD pathogenesis.

Val34Leu factor XIII polymorphism in Italian patients with inflammatory bowel disease

BACKGROUND

Coagulation Factor XIII is implicated in fibrin stabilization and wound healing. Plasma levels of Factor XIII are reduced in inflammatory bowel disease patients; recently, a valine 34 to leucine polymorphism of the Factor XIII-A subunit gene with a defined protective effect against thrombosis and as yet undetermined effect on wound healing has been described.

AIM

To evaluate Val34Leu Factor XIII polymorphism distribution and to find possible correlations with clinical features in Italian inflammatory bowel disease patients.

STUDY POPULATION

A total of 152 inflammatory bowel disease patients, 90 with ulcerative colitis and 62 with Crohn's disease and 130 healthy volunteers were studied.

METHODS

Val34Leu polymorphism was detected by RFLP with BsaH I. Statistical analysis was performed by means of Fisher exact test.

RESULTS

In inflammatory bowel disease, 57.2% of patients showed the wild type status, 37.5% were heterozygous and 5.3% were homozygous for the 34Leu allele; the frequency of the mutated allele was 24.0%. In controls, 66.1% of subjects showed the wild type status, 28.5% were heterozygous and 5.4% were homozygous for the 34Leu allele; the frequency of the mutated allele was 19.7%. There was no difference in genotype distribution and prevalence of the mutated allele between inflammatory bowel disease patients and controls.

CONCLUSIONS

The present data do not show any differences in Val34Leu Factor XIII polymorphism distribution between inflammatory bowel disease patients and controls. The prothrombotic state described in inflammatory bowel disease patients does not depend on an altered distribution of Val34Leu Factor XIII polymorphism.