Haemostasis in patients with Behçet's disease

Replication Study of the Association of GAS6 and PROS1 Polymorphisms with Behçet's Disease in a Japanese Population

PURPOSE

To investigate whether polymorphisms of GAS6 and PROS1, which each encode protein ligands for a family of tyrosine kinase receptors, are associated with Behçet's disease (BD) in a Japanese population.

METHODS

We recruited 734 Japanese patients with BD and 1789 Japanese healthy controls. In all participants, we genotyped two single-nucleotide polymorphisms (SNPs) reportedly associated with BD: rs9577873 in GAS6 and rs4857037 in PROS1.

RESULTS

We found that GAS6 rs9577873 was not significantly associated with BD. In contrast, PROS1 rs4857037, specifically the A allele, was associated with increased risk for BD. The A allele was also significantly associated with BD under additive and recessive genetic models. Expression analysis revealed that this allele was significantly associated with increased PROS1 expression.

CONCLUSIONS

Our findings suggest that increased PROS1 expression related to the A risk allele of rs4857037 affects tyrosine kinase receptor signaling, contributing to the development of BD.

Oral Lesions as the Primary Manifestations of Behçet's Disease: The Importance of Interdisciplinary Diagnostics-A Case Report

BACKGROUND

Behçet's disease (BD) is a rare chronic auto-inflammatory systemic disease with non-specific oral manifestations, categorised as generalised variable vessel vasculitis that requires an interdisciplinary approach to diagnose due to its phenotypic heterogeneity. Whilst the oral lesions that reoccur in BD underpin the complex diagnostic process, the crucial role of dental professionals is highlighted in a case report summarised herein. We present a case of a 47-year-old male referred to the Oral Medicine Department by a rheumatologist after previous hospitalization for thrombosis of the iliac vein and inferior vena cava. He had elevated inflammatory C-reactive protein biomarker and an increased erythrocyte sedimentation rate. Recurrent episodes of folliculitis, oral and genital ulcers were reported. Clinical examination revealed multiple ulcerations in the oral mucosa. The complementary, histopathological analysis performed to rule out other disorders, based on excisional biopsy, showed non-keratinised stratified squamous epithelium with areas of exocytosis and ulceration. The connective tissue presented an intense mixed inflammatory infiltrate, congested blood vessels, haemorrhage, vasculitis, and HLA-B genotyping identified the expression of HLA-B15, further supporting the BD diagnosis. Treatment was initiated with colchicine, prednisolone, and weekly subcutaneous administration of methotrexate and resulted in the complete remission of oral lesions and no recurrence of other manifestations.

CONCLUSIONS

This BD case report emphasizes the importance of a multidisciplinary approach in diagnosing BD, including the use of histopathological assessment and genetic profiling. It highlights the significance of thorough intraoral assessment and referral to a multidisciplinary team for diagnosis. The oral manifestations of BD as the primary symptoms often indicate underlying major systemic pathologies. The authors stress the need for a structured diagnostic algorithm to facilitate timely and effective management of BD.

Vascular Behçet syndrome: from pathogenesis to treatment

Behçet syndrome is a rare, chronic inflammatory disease of unknown aetiopathogenesis, most commonly presenting with mucocutaneous and ocular manifestations. Vascular involvement, most frequently superficial vein and deep vein thrombosis, can occur in up to 50% of patients with Behçet syndrome. Venous thrombosis at atypical sites (inferior and superior vena cava, suprahepatic veins with Budd-Chiari syndrome, portal vein, cerebral sinuses and right atrium and/or ventricle) and arterial involvement (mostly in situ thrombosis and aneurysms of the pulmonary arteries, as well as aneurysms of the abdominal aorta, and peripheral and visceral arteries) are also unique features of Behçet syndrome. Behçet syndrome is considered a natural model of inflammation-induced thrombosis in humans, with an impaired immune-inflammatory response rather than traditional cardiovascular risk factors contributing to thrombogenesis. Specifically, neutrophil hyperactivation and neutrophil-mediated mechanisms of damage directly promote endothelial dysfunction, platelet activation and thrombogenesis in Behçet syndrome. This unusual pathogenesis directly determines the treatment approach, which relies mostly on immunosuppressants rather than anticoagulants for treatment of thrombosis and for secondary prevention. This Review discusses the main histopathological, pathogenetic and clinical aspects of vascular Behçet syndrome, addressing their implications for therapeutic management. Future perspectives in terms of pathogenetic studies, disease monitoring and treatment strategies are also discussed.

Epidemiology, morbidity and mortality in Behçet’s disease: a cohort study using The Health Improvement Network (THIN)

Objectives

The epidemiology of Behçet’s disease (BD) has not been well characterized in the UK. Evidence on the risk of cardiovascular disease, thromboembolic disease and mortality in patients with BD compared with the general population is scarce.

Methods

We used a large UK primary care database to investigate the epidemiology of BD. A retrospective matched cohort study was used to assess the following outcomes: risk of cardiovascular, thromboembolic disease and mortality. Controls were selected at a 1:4 ratio (age and gender matched). Cox proportional hazard models were used to derive adjusted hazard ratios (aHR).

Results

The prevalence of BD was 14.61 (95% CI 13.35–15.88) per 100 000 population in 2017. A total of 1281 patients with BD were compared with 5124 age- and gender-matched controls. There was significantly increased risk of ischaemic heart disease [aHR 3.09 (1.28–7.44)], venous thrombosis [aHR 4.80 (2.42–9.54)] and mortality [aHR 1.40 (1.07–1.84)] in patients with BD compared with corresponding controls. Patients with BD were at higher risk of pulmonary embolism compared with corresponding controls at baseline [adjusted odds ratio 4.64 (2.66–8.09), P < 0.0001]. The majority of patients with pulmonary embolism and a diagnosis of BD had pulmonary embolism preceding the diagnosis of BD, not after (87.5%; n = 28/32).

Conclusion

BD has a higher prevalence than previously thought. Physicians should be aware of the increased risk of developing ischaemic heart disease, stroke/transient ischaemic attack and deep venous thrombosis in patients with BD at an earlier age compared with the general population. Risk of embolism in patients with BD might vary across the disease course.

Outcomes of vascular intervention and use of perioperative medications for nonpulmonary aneurysms in Behçet disease

BACKGROUND

Aneurysms attributable to Behçet disease (BD) are not common but are associated with a poor prognosis because of a high risk of rupture. Special considerations are required for vascular intervention, because the intense local inflammation may increase complications. The aim of this study was to assess the outcome of operative intervention and the use of perioperative medical therapy for aneurysms in patients with BD.

MATERIALS AND METHODS

We reviewed retrospectively the medical records of patients with BD admitted to Peking Union Medical College Hospital between January 1995 and January 2015.

RESULTS

Among 874 patients diagnosed with BD, 176 patients had vascular involvement, of whom 59 had arterial aneurysms. Thirty-six patients with 51 arterial aneurysms underwent operative intervention. The 51 primary operative interventions included 20 open operations and 31 endovascular interventions. Eleven (22 %) recurrent aneurysms developed in 10 patients and 5 (10%) thrombosis occurred in 5 patients. Of the 19 endovascular stents placed for aortic aneurysms, 1 type I endoleak, 1 graft occlusion, 3 recurrent aneurysms, and 1 recurrent aneurysmal rupture occurred. Among the revascularization procedures for extremity arteries, there were more complications with endovascular intervention than with open surgery. The cumulative risk of recurrent aneurysmal formation at the operative site was significantly less in patients treated with operative intervention combined with use of immunosuppressants than those treated with operative intervention alone (P = .01).

CONCLUSION

In patients with BD, an endovascular approach is feasible and effective for aortic aneurysms, whereas bypass surgery appears to provide better outcomes for extremity arterial aneurysms than placement of endovascular stents. The administration of corticosteroids combined with cyclophosphamide perioperatively decreases the cumulative risk of recurrent aneurysm.

Identification of possible pathogenic pathways in Behçet's disease using genome-wide association study data from two different populations

Behçet's disease (BD) is a multi-system inflammatory disorder of unknown etiology. Two recent genome-wide association studies (GWASs) of BD confirmed a strong association with the MHC class I region and identified two non-HLA common genetic variations. In complex diseases, multiple factors may target different sets of genes in the same pathway and thus may cause the same disease phenotype. We therefore hypothesized that identification of disease-associated pathways is critical to elucidate mechanisms underlying BD, and those pathways may be conserved within and across populations. To identify the disease-associated pathways, we developed a novel methodology that combines nominally significant evidence of genetic association with current knowledge of biochemical pathways, protein-protein interaction networks, and functional information of selected SNPs. Using this methodology, we searched for the disease-related pathways in two BD GWASs in Turkish and Japanese case-control groups. We found that 6 of the top 10 identified pathways in both populations were overlapping, even though there were few significantly conserved SNPs/genes within and between populations. The probability of random occurrence of such an event was 2.24E-39. These shared pathways were focal adhesion, MAPK signaling, TGF-β signaling, ECM-receptor interaction, complement and coagulation cascades, and proteasome pathways. Even though each individual has a unique combination of factors involved in their disease development, the targeted pathways are expected to be mostly the same. Hence, the identification of shared pathways between the Turkish and the Japanese patients using GWAS data may help further elucidate the inflammatory mechanisms in BD pathogenesis.

Haemostatic Parameters in Patients with Behçet's Disease

OBJECTIVES

This study aimed to evaluate the cause of thrombosis in Behçet's disease (BD) patients, since abnormalities in coagulation and fibrinolytic parameters have shown contradictory results.

METHODS

Haemostatic parameters were retrospectively evaluated in BD patients treated between January 2007 and January 2011 at Sultan Qaboos University Hospital, Oman. The blood samples of 35 Omani BD patients and 30 healthy controls were analysed for factor VIII:C levels, activated protein C resistance (APCR), von Willebrand factor (vWF) antigens (Ag), collagen binding and ristocetin co-factor activity (RiCoF), antithrombin (AT), protein C (chromogenic and clotting), protein S, homocysteine, tissue plasminogen activator, plasminogen activator inhibitor, plasminogen, alpha 2-antiplasmin, lupus anticoagulant and anticardiolipin and beta2-glycoprotein-1 antibodies.

RESULTS

The mean values of factor VIII:C, vWF Ag, AT and protein S were significantly higher in the patient group (P = 0.01, 0.006, 0.04 and 0.01, respectively). There was no deficiency in protein C. Screening for APCR, anticardiolipin antibodies, anti-beta2-glycoprotein-1 antibodies and lupus anticoagulant was negative and there were no differences in homocysteine levels, nor were there differences between patients with and without thrombosis. Six patients had elevated factor VIII:C levels (>150 IU/dL, P <0.02) which normalised on repeat measurements after three months.

CONCLUSION

The elevation of factors VIII:C, vWF Ag and AT most likely represent an acute phase phenomenon. In this study, thrombophilic factors did not seem to explain thrombotic tendency. Therefore, further mechanistic studies in a larger group of patients are needed to elucidate the basis for thrombosis in BD. We hypothesise that active BD causes vasculitic endothelial perturbation with dysfunction, leading to the observed increased propensity for thrombosis.

Behçet's disease: new insight into the relationship between procoagulant state, endothelial activation/damage and disease activity

BACKGROUND

Behçet disease (BD) is associated with a prothrombotic state of unknown origin that may lead to life-threatening events. Calibrated Automated Thrombogram (CAT) and Rotational Thromboelastometry (ROTEM) are two global haemostasis assays that may reveal new insights into the physiopathological mechanisms of the disease and its procoagulant condition.

METHODS

23 BD patients who had no signs or symptoms of current thrombosis and 33 age- and sex-matched controls were included in the study. We performed ROTEM and CAT tests and assessed erythrocyte count, platelet count, platelet contribution to clot formation and plasma levels of tissue-type plasminogen activator, plasminogen activator inhibitor type 1 (PAI-1), fibrinogen, C-reactive protein (CRP), thrombin-antithrombin III complex (TAT), D-dimer and E-selectin (ES).

RESULTS

Both ROTEM and CAT tests showed a hypercoagulable state in the BD patients. Plasma levels of PAI-1, fibrinogen, TAT, CRP and ES were significantly increased in this group compared to controls. The disease activity (DA) was significantly correlated with levels of ES and the maximum clot firmness, and this last one, in turn, correlated with rising levels of ES, PAI-1, CRP and fibrinogen. CAT parameters did not correlate with DA or ES.

CONCLUSIONS

Both ROTEM and CAT tests reveal that patients with BD have a procoagulant state even in the absence of thrombosis. ROTEM test indicates that increased levels of fibrinogen and PAI-1 may be involved in the prothrombotic state of this pathology, while platelets do not significantly contribute. Moreover, CAT assay demonstrate that plasma from BD patients is able to generate more thrombin than controls in response to the same stimulus and that this effect is independent of the DA and the endothelial impairment suggesting the involvement of another factor in the hypercoagulable state observed in BD patients. This study also shows that endothelium activation/damage may be a contributing factor in both the procoagulant and clinical conditions of BD, as shown by the direct correlation between ES levels, ROTEM parameters and DA.

Behcet's Disease: New Concepts in Cardiovascular Involvements and Future Direction for Treatment

Behcet's disease (BD) is the only systemic vasculitis involving both arteries and vein in any sizes. It frequently encounters in rheumatology clinics. It has some major morbidities and even fatal outcomes in some cases. The aim of this paper is to analyze the main concepts on pathophysiology and treatment options in BD, focusing on cardiovascular aspects, thrombosis, and potential future treatment.

Pediatric Behçet’s Disease and Thromboses

Objective.

To describe the characteristics of a group of pediatric patients with Behçet’s disease (BD) who presented at least 1 episode of thrombosis during their disease course.

Methods.

We made a retrospective chart review of the clinical, biological, and radiological data of children with BD who presented at least 1 episode of either arterial or venous thrombosis. Data were extracted from both an international pediatric Behçet cohort and files referred from 7 French centers.

Results.

Twenty-one patients were included. Diagnosis of BD was based on the criteria of the International Study Group for BD. Main locations for thrombosis were the cerebral sinuses, in 11 patients (52.4%); and lower limbs, in 9 patients (40.9%). Recurrent episodes were observed in 4 patients (21%). Thrombophilia measurements were normal in 14 patients out of 21, while anticardiolipin antibodies were positive in 4 patients, and 2 out of 21 had protein C deficiency. One patient had lupus anticoagulant. All patients were treated with colchicine. Corticosteroids were also added for variable periods in 13 patients. Five patients out of 21 were treated with anticoagulants (heparin, then anti-vitamin K) and 3 with antiplatelets (acetylsalicylic acid).

Conclusion.

Thromboses are a serious complication of BD and may occur early in the disease course. The presence of thrombophilic markers could increase the risk of thrombosis in BD, but the size of our population does not allow any conclusion. An international cohort (PED-BD) is currently in place and will allow study of such cases longitudinally, as well as assessment of the elements that correlate with an increased risk of thrombosis in children with BD.

Behçet's Disease as a Model of Venous Thrombosis

Behçet's disease (BD) is a chronic inflammatory disease of unknown aetiology characterized by recurrent oral, genital aphthous ulcerations, uveitis, skin lesions and other multisystem affections associated with vasculitis. Different types of vessels, predominantly veins, can be affected in BD. The frequency of vascular lesions in BD, such as superficial and deep venous thromboses, arterial aneurysms and occlusions, ranges between 7-29%. In this review, various factors of thrombogenesis in BD, particularly pro- and antithrombotic endothelial and non-endothelial factors, factors of coagulation, platelet activation and rheological changes are presented and discussed from positions of Virchow's triad of venous thrombosis. Despite advances in understanding of thrombogenesis in BD, still many issues of diagnosis and targeted preventive and therapeutic measures remain unresolved. Further studies are needed to clarify the pathobiology of BD-related thrombosis and to provide the clinicians with recommendations over the utility, safety and effectiveness of the antithrombotic therapy in BD.

Behçet’s Disease as a Model of Venous Thrombosis

Behçet’s disease (BD) is a chronic inflammatory disease of unknown aetiology characterized by recurrent oral, genital aphthous ulcerations, uveitis, skin lesions and other multisystem affections associated with vasculitis. Different types of vessels, predominantly veins, can be affected in BD. The frequency of vascular lesions in BD, such as superficial and deep venous thromboses, arterial aneurysms and occlusions, ranges between 7-29%.

In this review, various factors of thrombogenesis in BD, particularly pro- and antithrombotic endothelial and non-endothelial factors, factors of coagulation, platelet activation and rheological changes are presented and discussed from positions of Virchow’s triad of venous thrombosis.

Despite advances in understanding of thrombogenesis in BD, still many issues of diagnosis and targeted preventive and therapeutic measures remain unresolved. Further studies are needed to clarify the pathobiology of BD-related thrombosis and to provide the clinicians with recommendations over the utility, safety and effectiveness of the antithrombotic therapy in BD.

Major arterial involvement and review of Behcet's disease

Behcet's disease was first defined by Hulusi Behcetin 1937 as a multisystemic disorder with characteristic pathologic findings including recurrent orogenitalulcers, vascular disorders, and ocular and cutaneous lesions. The disease is mostly encountered at the third and fourth decades of life and especially prevalent in Mediterranean and Far East Asia.Behcet's disease may have both venous and arterial manifestations. The arterial form is rare but it is bore with its manner and to consider recurrent surgical treatments. In this retrospective study, we reviewed the literature related to Behcet's disease and discussed in respect to vascular involvement and the prognosis of surgical treatment.Thirty-one consecutive patients with vasculo-Behcet's disease visiting the departments of cardiovascular surgery, dermatology, and internal medicine in Medical Faculty of Istanbul have been reviewed retrospectively. All available clinical,pathologic, and postoperative data were reviewed and analyzed. Venous system pathologies were present in 15 patients. The pathologies in the remaining patients were related to the arterial tree. Ten patients with aneurysms and/or pseudoaneurysms and six patients with occlusive lesions have undergone surgical treatment. Pseudoaneurysms occurred in six patients at least twice or more. Vascular manifestations are the main predictors of mortality and morbidity in Behcet's disease. Arterial complications may lead to difficult surgical problems.Any invasive methods to arterial system may cause pseudoaneurysms. Repairs by using autogenous veins or synthetic grafts may lead to anastomotic false aneurysms. Surgical treatment should not to be applied in the acute phase of the disease and systemic therapy including colchicine, aspirin,and corticosteroids should be considered for all patients.

Decreased protein S activity is related to the disease activity of Behcet's disease

We wanted to see whether the active inflammation in Behcet's disease (BD) can cause a thrombotic disorder by decreasing the protein S (PS) activity, and we evaluated the relationship between the decreased PS activity and the disease activity of BD. We included 122 patients with BD whose PS activity levels were measured. In 51 patients, the PS activity was measured again when there were changes in the number of items of "The Behcet's Disease Current Activity Form (BDCAF)". The thrombosis rate was 2.5% (3/122), and the PS activity was low in all three of the patients with thrombosis. The incidence of low PS activity in the total 122 BD patients was 27% (33/122). The incidence of the low PS activity in the active BD patients was 33.7% (31/92), and this was significantly more frequent than in the inactive BD patients, (6.7%, 2/30) (chi(2)-test, P value = 0.0038). The decrease of PS activity had good correlation with the increase of the number of BDCAF items (r = -0.351, P value = 0.012). The PS activity decrease is related to the BD activity. The low PS activity can be the risk factor for thrombotic disorder and also the activity marker for BD and other inflammatory diseases.

Haemorheological alterations in Behçet's disease are not related to a tendency for venous thrombosis

INTRODUCTION

Behçet's disease is associated with an increased risk of thrombosis, although the prothrombotic mechanisms are unclear. Alterations in blood rheology, particularly increased erythrocyte aggregation, might play a role in the development of such thrombotic events.

MATERIALS AND METHODS

We measured plasma lipids, fibrinogen, haematocrit, erythrocite aggregation, erythrocyte deformability, blood viscosity, plasma viscosity and erythrocyte indexes in patients with a nonactive disease at sampling, and in a well-matched control group. The patient group comprised 42 patients with BD (21 male, 21 female aged 43+/-12 years) and the control group comprised 46 healthy volunteers (23 male, 23 female aged 45+/-13 years). Twelve of the 42 patients with BD had a previous documented history of deep vein thrombosis at least 6 months before entering the study, and the other 30 did not.

RESULTS

Compared with controls, patients showed statistically higher fibrinogen concentrations (P=0.001), plasma viscosity (P=0.002), blood viscosity (P=0.006) and erythrocyte aggregation, both at stasis (P=0.001) and at a low shear rate (P=0.002): the other rheological parameters were not statistically significant. No differences were observed in the rheological parameters when patients with and without previous thrombotic episodes were compared.

CONCLUSIONS

Although patients with BD show a moderate hyperviscosity syndrome, possibly related to chronic inflammation, this does not seem to play a role in the development of thrombotic events.

Von Willebrand factor antigen levels in Behçet disease

High von Willebrand factor antigen (vWF:Ag) levels can be found due to vascular endothelial injury in Behçet disease. The aim of this study is to evaluate whether there is any relationship between vWF:Ag levels and vascular or other organ involvements and acute-phase reactants in Behçet disease. Fifteen controls and 17 Behçet's patients were included; 10 had oral ulcers, 5 had genital ulcers, 3 had skin lesions, 6 had ocular involvement, 5 had arthritis, and 6 had vascular involvement. VWF:Ag levels were higher in Behçet's patients than controls. VWF:Ag levels in Behçet's patients with oral ulcers, genital ulcers, and ocular and vascular involvement were statistically higher than in the control group. Differences between vWF:Ag levels in Behçet's patients with and without organ involvement were not statistically significant. A linear correlation between serum ferritin levels and vWF:Ag levels was observed. These results demonstrate that elevated levels of plasma vWF:Ag are related to Behçet disease exacerbation rather than vascular involvement.

Activated protein C levels in Behçet's disease and risk of venous thrombosis

Behçet's disease is a multi-systemic inflammatory disorder of unknown cause. Most abnormalities have been associated with endothelial injury caused by vasculitis. Thrombosis occurs in about 25% of patients, although the mechanism is unknown. The objective of this study was to evaluate the protein C activation system in Behçet's disease and its correlation with venous thromboembolism (VTE). Thirty-nine patients (12 with VTE) and 78 age- and sex-matched controls were included in the study, and levels of protein C, protein S, activated protein C (APC), protein C inhibitor (PCI), soluble thrombomodulin (TM), antithrombin (AT), alpha(1)-antitrypsin, fibrinogen, factor VIII, von Willebrand factor (VWF) and C-reactive protein (CRP) were measured. APC and TM levels were significantly lower in patients than in controls, whereas protein S, AT, alpha(1)-antitrypsin, fibrinogen, factor VIII, VWF and CRP levels were significantly higher in patients than in controls. APC, PCI and TM levels were lower in patients with VTE (0.65 +/- 0.19 ng/ml, 86% +/- 22% and 15.5 +/- 7.1 ng/ml respectively) than in those without VTE (0.78 +/- 0.17 ng/ml, 100% +/- 15% and 22.1 +/- 15.3 ng/ml) (P < 0.05). In patients, APC levels below 0.75 ng/ml (10th percentile of the control group) increased the risk of VTE about fivefold (odds ratio = 5.1; 95% confidence interval = 1.1-23.4). These results show that reduced APC levels are associated with the high incidence of VTE in Behçet's disease.

Comparison of Morphological and Functional Alterations of Human Saphenous Veins after Seven and Fourteen Days of ex vivo Perfusion

Intimal hyperplasia (IH) is a vessel wall remodeling process responsible of early failure after vascular surgery or endovascular interventions. An ex vivo perfusion was used to study human venous segments regarding functional, histomorphological, immunohistochemical and molecular alterations after 7 (group 1, n = 6) and 14 days (group 2, n = 6) of ex vivo perfusion. All vessel segments showed preserved smooth muscle function before and after perfusion. Histomorphometry revealed IH development which was more pronounced after 14 days rather than 7 days (p < 0.05). Expression of CD34, factor VIII, alpha-actin and MIB-1 was demonstrated in all segments from both groups indicating that muscular and endothelial integrity was preserved after ex vivo perfusion of up to 14 days. PAI-1 mRNA expression was significantly increased after perfusion (p < 0.05), suggesting that the endothelial fibrinolytic function may be modulated in this ex vivo perfusion model of human saphenous veins.

Vascular endothelial and basic fibroblast growth factor serum levels in patients with Behçet’s disease

Behçet's disease (BD) is a systemic vasculitis of unknown aetiology. Its pathogenesis is related to endothelial cell dysfunction, humoral immune defects, and immune system dysregulation. The aim of this study was to investigate the possible role of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in the pathogenesis of BD. We also investigated whether disease activity, age, or duration of BD correlates with VEGF and bFGF. We studied 33 patients and 20 healthy controls. Vascular endothelial growth factor and bFGF serum levels were measured by enzyme-linked immunosorbent assay. We measured acute phase reactants, including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). The mean serum VEGF level was significantly higher in patients with BD (398.8+/-222.2 pg/ml) than the control group (193.0+/-122.4 pg/ml) (P=0.002). The levels were similar in both active and inactive BD (P=0.675) but did not correlate with disease duration, CRP, ESR, or age (P>0.05 for each). The bFGF was below detection limits in 18 of 33 patients with BD and ten of 20 controls, and its mean serum level was higher in BD patients (42.4+/-76.9 pg/ml) than controls (29.0+/-9.1 pg/ml), but this difference was not statistically significant (P=0.232). The bFGF levels were similar in both active and inactive BD (P=0.09) and, in patients, correlated with disease duration and CRP (r=0.58, P=0.02; r=-0.57, P=0.02, respectively) but not with ESR or age (P>0.05 for each). Vascular endothelial growth factor may be more important in the pathogenesis of BD than bFGF. Neither growth factor is an activity criterion or inflammatory marker in BD.

Endothelial cell activation and hypercoagulability in ocular Behçet's disease

PURPOSE

To investigate the presence of a hypercoagulable state and vascular endothelial dysfunction in patients with ocular Behçet's disease and relate the results to the activity of ocular and systemic involvement.

DESIGN

Cross-sectional laboratory and clinical study.

METHODS

Prospective study of blood samples of 24 patients diagnosed with ocular Behçet's disease, which were analyzed for factor VIII, factor XI, von Willebrand factor antigen and ristocetin (vWF ag and risto), antithrombin III (ATIII), protein C and S, fibrinogen and activated protein C (APC) resistance. The results were compared with 40 healthy controls and analyzed for association with ocular and systemic clinical features.

RESULTS

The mean values of factor VIII, factor XI, vWF ag, vWF risto, ATIII, and fibrinogen were significantly raised compared to healthy population (for all: P <.001). Most striking were factor VIII activity levels above 130% in 79% (19 of 24) of our patients. 67% (16 of 24) had levels of factor VIII above 150%, which correlates with a fivefold increase in risk of thrombosis. Other prothrombogenic factors were negative in all but 2 patients (1 protein C deficiency, 1 factor V Leiden mutation). Endothelial cell activation, measured by vWF activity, revealed elevated levels in 42% (10/24). Complete/incomplete Behçet's disease patients with present or previous macular edema had significantly higher FVIII levels than complete/incomplete Behçet's disease patients who had never shown any signs of macular edema (P =.04). Further correlations between the laboratory results and clinical symptoms were not found.

CONCLUSIONS

We found a generalized hypercoagulable state with endothelial cell activation in ocular Behçet's disease, irrespectively of current ocular disease activity.

Coagulation parameters and plasma total homocysteine levels in Behcet's disease

Behcet's disease (BD) is a multisystemic inflammatory disorder of unknown etiology that is sometimes associated with thrombosis in addition to systemic manifestations. However, the mechanism of hypercoagulability is not known. We evaluated the coagulation and fibrinolytic activities and the plasma total homocysteine levels of Korean BD patients in two cross-sectional studies. In the first study regarding coagulation and fibrinolytic activities, the levels of fibrinogen and von Willebrand factor (vWF) antigen were significantly higher in the BD patients than in the healthy controls (387.7+/-24.3 versus 240.6+/-8.8 mg/dl, p<0.001, and 131.9+/-8.8 versus 105.2+/-0.3%, p<0.01, respectively). The level of antithrombin III (AT III) was significantly lower in the BD patients (92.8+/-3.2 versus 106.3+/-2.6%, p<0.005). No differences were observed in the levels of plasminogen, protein C, or protein S activities. Activated protein C (APC) resistance was not observed in any BD patients. In the second study, the plasma total homocysteine levels of patients with a history of thrombosis (11.9+/-3.0 micromol/l) or disease activity (12.5+/-3.8 micromol/l) were found to be significantly higher than those of the controls (9.2+/-2.6 micromol/l, p<0.05, both). The plasma homocysteine concentrations in the thrombosis patients were positively correlated with plasma vWF levels; a relationship which suggests injury of the vascular endothelium (Spearman coefficient=0.857, p<0.01). Therefore, coagulation abnormality did not contribute to thrombotic complications, and higher levels of homocysteine may play a role in the hypercoagulablity of BD patients.

Vascular involvement in Behçet's disease: relation with thrombophilic factors, coagulation activation, and thrombomodulin

PURPOSE

Thrombosis, usually venous, occurs in 10% to 25% of patients with Behçet's disease, but its pathogenesis is poorly understood. We evaluated parameters of hemostasis and their relation with thrombosis in a series of patients with Behçet's disease.

SUBJECTS AND METHODS

We studied 38 patients with Behçet's disease (13 with venous thrombosis), 38 patients with venous thrombosis without thrombophilia, and 100 control subjects. Levels or presence of protein C, protein S, antithrombin, methylenetetrahydrofolate reductase C677T, factor V Leiden, prothrombin gene G20210A, antiphospholipid antibodies, plasminogen, tissue-type plasminogen activator (tPA), type-1 tPA inhibitor (PAI-1), PAI-1 4G/5G polymorphism, prothrombin fragment 1+2, plasmin/alpha(2)-antiplasmin complexes, thrombomodulin, and activated factors VII and XII were determined.

RESULTS

There were no deficiencies in protein C, protein S, antithrombin, or factor V Leiden in the patients with Behçet's disease, nor was there evidence of most other thrombotic abnormalities. Compared with control subjects, however, the Behçet's disease group had elevated mean (+/- SD) levels of prothrombin fragment 1+2 (2091 +/- 1323 pmol/L vs. 804 +/- 398 pmol/L, P <0.001), plasmin/alpha2-antiplasmin complexes (410 +/- 220 microg/L vs. 214 +/- 92 microg/L, P <0.001), and thrombomodulin (37 +/- 24 ng/mL vs. 27 +/- 10 ng/mL, P <0.001). These levels did not differ between patients with or without thrombosis.

CONCLUSIONS

Thrombophilic factors do not seem to explain most thromboses in Behçet's disease. There is increased thrombin generation, fibrinolysis, and thrombomodulin in Behçet's disease, but these abnormalities are not related to thrombosis.

Natural course of the functional and morphological changes in canine autogenous arterial graft

BACKGROUND

We examined the time course of endothelium-dependent and -independent responses in reversed autogenous arterial grafts during regeneration and tissue repair processes after arterial grafting in dogs.

MATERIALS AND METHODS

Autogenous arterial grafts implanted in the canine femoral artery were removed, cut into rings and suspended in organ chambers for isometric tension recording on the 1st, 3rd, 7th, 14th and 28th days after implantation. Electron-microscopic examination on the 1st, 3rd,7th, 14th and 28th days after transplantation was also performed. Control arteries were taken from nonsurgically treated femoral arteries.

RESULTS

Acetylcholine (ACh) and A23187 caused endothelium-dependent relaxations in arterial grafts throughout the study. Although endothelium-dependent relaxations to ACh and A23187 on the 3rd day after transplantation were only significantly impaired compared to those of control, they were similar to the control within 1 week after grafting. Smooth muscle relaxations in response to sodium nitroprusside in arterial grafts throughout the study were comparable with those of control arteries. No apparent intimal thickening of the arterial grafts was observed. Electron microscopy scanning revealed mild endothelial cell damage in implanted autogenous arterial grafts on the 1st or 3rd day after grafting. Seven to 14 days after grafting, the endothelial cell layer appeared to be normal.

CONCLUSIONS

It was observed that the endothelial function remained intact and there was an absence of intimal thickening in the arterial grafts. These observations may explain the improved patency of autogenous arterial grafts compared to the vein grafts in aortocoronary revascularization.

Reoperation results of arterial involvement in Behçet's disease

OBJECTIVES

to retrospectively evaluate the role of vascular interventions in Behçet's disease with arterial involvement. So far, little information is available on the surgical approach for arterial involvement in Behçet's disease.

MATERIAL AND METHODS

between February 1989 and August 1997, among 178 patients with Behçet's disease referred to our clinic, vascular involvement was established in total of 67 patients (38%) which consisted of 59 venous (33%) and 12 (7%) arterial involvements requiring urgent surgical intervention. Primary arterial lesions were occlusive in one patient, aneurysm formation in nine or both in four.

RESULTS

twelve primary operations and 12 reoperations were performed. The reasons for reoperations were anastomotic aneurysms, graft occlusion, occlusion of native vessel, graft infection, bleeding from anastomosis and aortoenteric fistula. First reoperation was performed after a mean period of 6.4 months (1-15 months). Postoperative follow-up was 12-60 months (mean 36 months) and three patients died during follow-up.

CONCLUSIONS

the surgical results were not satisfactory because of progressive graft thrombosis and formation of new aneurysms at the anastomosis. Aggressive medical treatment should be combined when major vessel involvement occurs. All types of arterial punctures for angiography or blood gases should be minimised because of the risk of new aneurysm formation. Surgical intervention is indicated only in patients with a growing aneurysm, acute rupture or severe ischaemia.