Homocysteine: An activity marker in Behçet's disease?

Finding the Needle in the Haystack: Serological and Urinary Biomarkers in Behçet's Disease: A Systematic Review

Urinary and serological markers play an essential role in the diagnostic process of autoimmune diseases. However, to date, specific and reliable biomarkers for diagnosing Behçet's disease (BD) are still lacking, negatively affecting the management of these patients. To analyze the currently available literature on serological and urinary BD biomarkers investigated in the last 25 years, we performed a systematic literature review using the Population, Intervention, Comparison, and Outcomes (PICO) strategy. One hundred eleven studies met the eligibility criteria (6301 BD patients, 5163 controls). Most of them were retrospective, while five (5%) were prospective. One hundred ten studies (99%) investigated serological biomarkers and only two (2%) focused on urinary biomarkers. One hundred three studies (93%) explored the diagnostic potential of the biomolecules, whereas sixty-two (56%) tested their effect on disease activity monitoring. Most articles reported an increase in inflammatory markers and pro-oxidant molecules, with a decrease in antioxidants. Promising results have been shown by the omics sciences, offering a more holistic approach. Despite the vast number of investigated markers, existing evidence indicates a persistent gap in BD diagnostic/prognostic indices. While new steps have been taken in the direction of pathogenesis and disease monitoring, international efforts for the search of a diagnostic marker for BD are still needed.

Plasma Homocysteine in Behcet's Disease: A Systematic Review and Meta-Analysis

AIM

 To evaluate the relevance of plasma homocysteine (HC) in Behcet's disease (BD) and its clinical manifestations.

METHODS

 Systematic review of EMBASE and PubMed databases according to PRISMA guidelines from inception to July 2021; random-effects meta-analyses for continuous outcomes.

RESULTS

 The search strategy retrieved 48 case-control (2,669 BD and 2,245 control participants) and 5 cohort studies (708 BD participants). Plasma HC was higher in BD than in controls (p < 0.0001) with wide heterogeneity (I2  = 89.7%) that remained unchanged after sensitivity analysis according to year of article publication, age of BD participants, study size, study quality, method of HC determination, and male/female ratio >1.5; some pooled ethnicities explained a small part of the heterogeneity (I2  = 16.3%). Active BD participants had higher HC than inactive ones (p < 0.0001), with moderate heterogeneity (I2  = 49.2%) that disappeared after removal of an outlier study with very high disease activity. BD participants with any vascular involvement had higher HC than those without (p < 0.0001) with wide heterogeneity (I2  = 89.7%); subgroup analysis on venous thrombosis only changed neither effect size (p < 0.0001) nor heterogeneity (I2  = 72.7%). BD participants with ocular involvement had higher HC than those without (p < 0.0001) with moderate heterogeneity (I2  = 40.3%).

CONCLUSION

 Although causality cannot be inferred, the consistency of the elevation of plasma HC in BD, particularly in patients with active disease, with vascular and ocular involvement suggests an intrinsic involvement of HC in these clinical manifestations.

The relationships of serum homocysteine levels and traditional lipid indicators with disease activity and coronary artery involvement in Takayasu arteritis

Serum homocysteine (HCY) levels have been associated with the occurrence of coronary stenosis and disease activity in large-vessel vasculitis. However, whether increases in serum HCY levels and traditional lipid indicators are associated with coronary artery involvement and disease activity in Chinese Han Takayasu arteritis (TA) patients is unknown. This study aims to investigate the clinical and laboratory features of TA by assessing their association with disease activity in TA patients, and to explore the risk factors associated with coronary artery involvement in these patients. Serum HCY levels and traditional lipid indicators were tested in one hundred ninety TA patients and one hundred fifty-four healthy controls. We analyzed the relationships of serum HCY levels and traditional lipid indicators with disease activity and analyzed the risk factors for coronary artery involvement. Twenty-one TA patients were found to have coronary artery stenosis (≥ 50%). TA patients had significantly higher levels of HCY than did healthy controls (p < 0.0001). Serum levels of HCY and low-density lipoprotein cholesterol (LDL-C); the ratios of LDL-C to high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC) to HDL-C, and triglycerides (TG) to HDL-C; and the values of atherogenic index of plasma (AIP) were significantly higher in patients with active TA than in patients with inactive TA and in TA patients with coronary artery involvement than in TA patients without coronary artery involvement. By contrast, the serum levels of HDL-C were significantly lower in patients with active TA than in patients with inactive TA and in TA patients with coronary artery involvement than in TA patients without coronary artery involvement (p < 0.05). In addition, the serum levels of TC and TG were significantly higher in TA patients with coronary artery involvement than those in TA patients without coronary artery involvement. Elevated serum HCY levels increased the risk of coronary artery involvement by 1.3-fold (p = 0.011, odds ratio [OR] = 1.275, 95% confidence interval [CI]: 1.056-1.539), and the cutoff value for serum HCY was 9.55 μmol/L. Elevated serum TG levels increased the risk of coronary artery involvement by 3.5-fold (p < 0.0001, OR = 3.534, 95% CI: 1.907-6.547), and the cutoff value for serum TG was 1.215 mmol/L. The risk of coronary artery involvement was 2.5-fold higher when an elevated TG/HDL-C ratio was present (p < 0.0001, OR = 2.513, 95% CI: 1.567-4.032). This study showed that serum HCY and TG levels and the TG/HDL-C ratio are independent risk factors for coronary artery involvement in TA patients.

The association of inflammatory markers and echocardiographic parameters in Behçet's disease

Background: The main objective of the current study is to find out if any association exists between specific inflammatory markers such as homocysteine (Hcy) and pentraxin-3 (PTX-3) and cardiac involvement determined by means of echocardiographic parameters in patients with Behçet disease (BD).Methods: From January 2011 to January 2012, a total of 62 Behçet's patients were enrolled in the study. Thirty-two healthy subjects constituted the control group. The diagnosis of BD was made as proposed by International Study Group of BD.Results: The mean PTX-3, Hcy, and C-reactive protein levels were significantly higher in patients with BD compared to the control group. The electromechanical delay (EMD) times were found to be prolonged in patients with BD. Also, the aortic stiffness index (SI) and elastic modulus (Ep) were significantly higher, while the aortic dispensibility was significantly lower in patients with BD. The left atrial volume, left atrial volume index, E/A ratio, E/E' septal, IRight-EMD, PA'-ML, PA'-MS, PA'-TL, SI, and Ep were correlated with PTX-3 levels. In addition, the E/A, PA'-ML, PA'-MS, SI, and Ep displayed correlation with Hcy levels in patients having BD.Conclusion: Elevated levels of PTX-3 and Hcy were found to be correlated with cardiac involvement determined by means of echocardiographic parameters in patients with BD.

Evaluation of atherogenic laboratory markers in Behçet's disease patients with vascular involvement

INTRODUCTION

Behçet's disease is a chronic inflammatory vasculitis presenting with immunological and endothelial changes. The aim of the present study is to evaluate blood levels of diagnostic markers which can be used in Behçet's patients with vascular involvement.

MATERIAL AND METHODS

Fifty Behçet's patients (22 with vascular involvement) and 30 healthy controls were included in the study. High-sensitivity C-reactive protein (hsCRP), erythrocyte sedimentation rate (ESR), tumor necrosis factor-α (TNF-α), apolipoprotein A1 (apoA1), apolipoprotein B (apoB), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride, total cholesterol, Lp-plA-2, homocysteine and ischemia modified albumin (IMA) levels were analyzed. Statistical analysis was performed with the SPSS program version 11.0. p < 0.05 was accepted as statistically significant.

RESULTS

hsCRP, TNF-α, homocysteine, IMA, apoA1, apoB, HDL, Lp-pla2 and ESR levels in patient and control groups were significantly different (p < 0.001, p = 0.001, p < 0.001, p < 0.001, p = 0.005, p < 0.001, p < 0.001, p < 0.001 and p = 0.003 respectively). In Behçet's patients with vascular involvement, homocysteine, TNF-α and Lp-pla2 levels were significantly higher than in Behçet's patients without vascular involvement (p = 0.035, p = 0.010 and p < 0.001 respectively).

CONCLUSIONS

Increased levels of inflammatory and atherogenic markers in Behçet's patients are an expected outcome due to the inflammatory nature of the disease. Especially, elevated levels of homocysteine, TNF-α and Lp-pla2 make them candidate diagnostic tools to be helpful in clinical evaluation of Behçet's disease patients with vascular involvement.

Hyperhomocysteinemia: a cardiovascular risk factor in autoimmune diseases?

Epidemiological studies conducted over the past 25 years have provided ample support for the association of mild hyperhomocysteinemia (HHcy) with an elevated risk of atherothrombosis. Since autoimmune disorders (AD) are frequently associated with relevant and early signs of atherothrombotic damage not adequately explained by the traditional risk factors involved in the onset of cardiovascular disease (CVD), a large interest has been shown to the putative role of mild HHcy in this setting. On the basis of such considerations, we focused the attention on the relationship between homocysteine (Hcy) and CVD in patients affected with autoimmune diseases, reviewing the most recent literature data and also providing our original experience. Although the large amount of available studies clearly shows that HHcy represents a common finding in patients affected with several autoimmune diseases, the actual role of Hcy in the development of CVD in the course of AD is not clear yet, perhaps, with the only exception of the systemic lupus erythematosus. In the other conditions, the role of Hcy in the pathogenesis of vascular complications is still a matter of debate, as the result of conflicting reports and/or lack of an adequate body of investigation. Lupus (2007) 16, 852—862.

Evaluation of Serum Homocysteine and Leptin Levels in Patients with Uveitis

OBJECTIVES

To evaluate the serum homocysteine (Hcy) and leptin levels in patients with uveitis.

MA­TE­RI­ALS AND MET­HODS

The 70 cases included in the study comprised 3 groups: patients with Behçet's uveitis (BU), patients with non-Behçet's uveitis (NBU) and healthy controls. Body mass index was calculated for each subject. Serum Hcy and leptin levels were measured. Furthermore, acute-phase reactants including erythrocyte sedimentation rate (ESR), C-reactive protein and neutrophil count were measured.

RE­SULTS

Serum Hcy levels were 15.04±4.59 µmol/L in the BU group, 15.4±6.87 µmol/L in the NBU group and 13.64±4.72 µmol/L in the control group (p>0.05). The serum leptin levels of male patients in the BU group, NBU group and control group were 4.76±3.54 ng/ml, 6.33±3.74 ng/ml and 5.47±6.33 ng/ml, respectively (p>0.05). When we compared serum leptin levels in female patients and controls, the mean serum leptin concentrations were significantly higher in female BU and NBU patients (24.83±17.62 ng/ml and 28.46±13.90 ng/ml, respectively) than in healthy control volunteers (9.62±6.36 ng/ml, p<0.05). In addition, the ESR value differences between groups were statistically significant (p<0.05).

CONCLUSION

A larger case series is necessary to investigate serum Hcy and leptin concentrations in uveitis patients.

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.

Neutrophil–Lymphocyte Ratio and Carotid–Intima Media Thickness in Patients With Behçet Disease Without Cardiovascular Involvement

Behçet disease (BD) is associated with endothelial dysfunction and chronic inflammation. The neutrophil–lymphocyte (N/L) ratio and carotid intima–media thickness (cIMT) are markers of inflammation and vascular risk, respectively. We assessed the relationship between cIMT values and N/L ratio in BD (65 patients and 62 control participants). There were statistically significant differences in N/L ratios and cIMT values between the patients with BD and control group ( P < .001). There were moderate positive correlations between cIMT value, C-reactive protein, and N/L ratio in patients with BD. Receiver–operating characteristic curve analysis suggested that the optimum N/L ratio cutoff point for patients with BD was 1.29, with a sensitivity, specificity, negative predictive value, and positive predictive value of 97, 77, 96, and 75%, respectively (area under curve: 0.691, 95% confidence interval = 0.600-0.782, P < .001). The N/L ratio may be a useful index of BD activity.

Outcome measures used in clinical trials for Behçet syndrome: a systematic review

Behçet syndrome (BS) is a multisystem vasculitis that is most active during young adulthood, causing serious disability and significant impairment in quality of life. Differences in the disease course, severity, and organ involvement between patients, depending on the age at presentation and sex, makes it impossible to determine a single management strategy. The diversity and variability in the outcome measures used in clinical trials in BS makes it difficult to compare the results or inform physicians about the best management strategy for individual patients. There is a large unmet need to determine or develop validated outcome measures for use in clinical trials in BS that are acceptable to researchers and regulatory agencies. We conducted a systematic review to describe the outcomes and outcome measures that have been used in clinical trials in BS. This review revealed the diversity and variability in the outcomes and outcome measures and the lack of standard definitions for most outcomes and rarity of validated outcome tools for disease assessment in BS. This systematic literature review will identify domains and candidate instruments for use in a Delphi exercise, the next step in the development of a core set of outcome measures that are properly validated and widely accepted by the collaboration of researchers from many different regions of the world and from different specialties, including rheumatology, ophthalmology, dermatology, gastroenterology, and neurology.

The relationship between plasma homocysteine level and HLA-B51 in patients with Behcet's disease: a case-control study

BACKGROUND

Various coagulation disorders have been reported to explain hypercoagulability state in Behcet's disease (BD). A possible negative association between human leukocyte antigen (HLA)-B51 and increased homocysteine level has been suggested in a previous report from Iranian patients with BD. The aim of this study was to find any possible relationship between plasma homocysteine levels and HLA-B51.

METHODS

In a case-control study, BD patients (fulfilling the new International Criteria for BD) and controls (who had similar clinical symptoms but BD was clinically excluded in them) were included. Mean plasma homocysteine levels measured by enzyme-linked immunosorbent assay in HLA-B51 positive and negative individuals both in patients and controls were compared by t-test, Mann-Whitney test and analysis of variance (F-test).

RESULTS

Ninety-six BD patients and 152 controls were recruited. There was no significant difference between HLA-B51 positive and negative individuals either in the mean plasma homocysteine levels (13.59 ± 9.03 vs. 12.95 ± 4.98 μmol/L, P = 0.514), or in the prevalence of hyperhomocysteinemia (17% vs. 21.4%, P = 0.504). This was true both for BD and control groups. In HLA-B51 positive and negative BD patients, mean plasma homocysteine levels were 14.29 ± 12.02 and 12.62 ± 4.79 μmol/L, respectively (P = 0.33), and the prevalence of hyperhomocysteinemia was 20.8% versus 19.5% (P = 0.55). In the control group, the mean plasma homocysteine levels in HLA-B51 positive and negative individuals were 12.85 ± 4.28 and 13.14 ± 5.10 μmol/L, respectively (P = 0.794), and the prevalence of hyperhomocysteinemia was 13% versus 22.1% (P = 0.23). The difference was non-significant regarding sex (P > 0.71) and disease activity (P > 0.31).

CONCLUSION

In contrast to our previous report, we found no relationship between plasma homocysteine levels and HLA-B51 in this study, either in BD or in the control group.

Markers of Endothelial Dysfunction and Evaluation of Vascular Reactivity Tests in Behçet Disease

We assessed endothelial dysfunction (ED) in patients with Behcet disease (BD; n = 40) and healthy controls (n = 20). Serum lipid, homocysteine, asymmetric dimethylarginine (ADMA) and high-sensitivity C-reactive protein (hsCRP) levels, erythrocyte sedimentation rates (ESRs), and ultrasonographic flow-mediated dilatation (FMD) were measured. Mean hsCRP, ESR, homocysteine, and ADMA were significantly higher in the BD group ( P < .001 for all). Patients with active BD had higher serum levels of hsCRP, homocysteine, and ESR compared with those in remission ( P < .001, P < .001, and P = .005, respectively). Flow-mediated dilatation was significantly lower in patients with BD than in controls ( P = .001). Flow-mediated dilatation correlated negatively with BD duration and serum ADMA levels ( P < .001, r = −.745 and P < .001, r = −.682); a positive correlation was seen between serum ADMA levels and BD duration ( P < .001, r = .552). Only stepwise multivariate regression analysis revealed BD duration to have a significant effect on FMD. Flow-mediated dilatation, in conjunction with markers of inflammation, may evaluate ED in patients with BD.

Activated protein C resistance in Behcet's disease

Behcet's disease is a chronic multi-system disorder of unknown etiology with protean manifestations. Venous thromboembolism is more common than arterial thrombosis, with deep vein thrombosis being the most frequent. Endothelial dysfunction resulting from vascular inflammation is considered to be an important factor of thrombosis, although the endothelial injury itself cannot completely explain the hypercoagulable state of the disease because other vasculitis syndromes do not increase the risk of thrombosis. The aim of this study is to evaluate the prevalence of activated protein C resistance (APC-R) in Egyptian patients with Behcet's disease. Also, to detect hyperhomocysteinemia in selected cases (with vascular complications) to assess their relationship with thromboembolic complications. The APC resistance ratio mean in the group of patients with vascular involvement was 2.6 ± 0.8 which was less than the group with no vascular involvement 2.8 ± 0.6, with non- significant P-value (0.5). There was more incidence of ocular lesions in the group of patients with high homocysteine level than the group of patients with normal homocytsteine level with significant P-value (0.08).

Adiponectin levels, insulin resistance and their relationship with serum levels of inflammatory cytokines in patients with Behçet's disease

AIM

Increased frequency of cardiovascular disease and its possible relations with insulin resistance have been reported in patients with inflammatory diseases. The aim of our study was to investigate insulin resistance and serum adiponectin levels as cardiovascular risk markers in patients with Behçet's disease.

METHOD

Study population consisted of 40 patients with Behçet's disease (BD) and a control group composed of age, gender, body mass index-matched 46 healthy individuals. All patients were examined for signs of Behçet's disease. Body mass index, waist and hip circumference were measured. Insulin resistance was evaluated using the homeostasis model assessment-insulin resistance method. Erythrocyte sedimentation rate (ESR), lipid profile, high sensitive CRP (hsCRP), adiponectin, TNF-α, IL-6 and IL-8 levels were measured.

RESULTS

Erythrocyte sedimentation rate, serum hsCRP and IL-6 levels were significantly higher in patients with BD than those in the controls (P=0.001, P=0.001, P=0.001, respectively). Fasting plasma glucose, insulin levels and lipid profile were not different between the two groups. Insulin resistance and decreased levels of the serum adiponectin were not detected in the patients. There was no relationship between insulin resistance, adiponectin levels and inflammatory markers. Active and inactive patients did not differ in respect of any parameters.

CONCLUSION

Being a systemic vasculitis, BD may cause cardiovascular involvement. In this study, dyslipidemia, insulin resistance and low adiponectin levels were not detected among our patients with Behçet's disease. Our results suggest that there exists no increased risk for atherosclerotic cardiovascular disease associated with adiponectin levels and insulin resistance in patients with Behçet's disease.

Hyperhomocysteinaemia in Behçet's Disease

Objectives. The aim of this study was to investigate if hyperhomocysteinaemia is a contributive risk factor for the pathogenesis and the activity of Behçet's disease (BD). Design and Methods. Fifty four patients fullfiling the criteria of the International Study Group for BD were enrolled. Fifty healthy volunteers matched for age and sex with the BD group were included as a negative control group. Patients, with any condition that might affect plasma homocysteine concentration, were excluded. Results. Mean serum homocysteine concentration was significantly higher in patients with BD than in the healthy controls (P < .001), in patients with active disease (P = .04), and in masculine gender (P = .05). There was no significant difference between homocysteine level and clinical involvement. Conclusions. We demonstrated that plasma total homocysteine level (tHcy) is increased in BD and correlated with disease activity. No association was found between homocysteine levels and clinical involvement.

A case of Hughes-Stovin syndrome associated with hyperhomocysteinemia

We report a case of Hughes-Stovin syndrome (HSS) associated with hyperhomocysteinemia. A 24-year-old man who has no clinical features suggestive of Behcet's disease was admitted for hemoptysis and dyspnea. Radiological and laboratory evaluation revealed multifocal pulmonary artery aneurysms involving bilateral segmental pulmonary artery, thrombi in right atrium and ventricle, and hyperhomocysteinemia. Accordingly, HSS associated with hyperhomocysteinemia was diagnosed, and the clinical and radiological improvement was achieved after treatment with prednisolone, warfarin, and folic acid.

Homocysteine levels in patients with Behçet's disease and patients with recurrent aphthous stomatitis

The mechanism for vascular involvement of Behçet disease (BD) includes arterial and venous thrombosis. Although the exact etiology of systemic vasculitis and thrombosis is still unknown, many hypotheses have been suggested. One of these hypotheses is that hyperhomocysteinemia causes vascular disease and thrombosis. The aim of this study was to compare the levels of homocysteine, vitamin B(12), and folic acid of BD patients with those of recurrent aphthous stomatitis (RAS) patients and healthy controls. Forty-five BD patients, 47 RAS patients, and 69 healty control subjects were included in this study. Vitamin B(12), folic acid, and homocysteine levels of the patients and controls were measured, and statistical differences among the groups were determined. BD patients had mostly cutaneous symptoms. Arthritis and ocular and vascular involvement were seen in 24.4%, 22%, and 11% of BD patients, respectively. No significant difference was detected among the groups in the levels of vitamin B(12), folic acid, and homocysteine. There was no significant difference in any parameters according to sex and age of the patients and activity of BD and if the patients with BD were treated or not. Homocysteine level inversely correlated with vitamin B(12) and folic acid levels in the BD group. We could not find any differences in homocysteine, vitamin B(12), and folic acid levels between BD and RAS patients and controls. This may be due to the fact that our patients mostly had cutaneous symptoms rather than vascular involvement.

Homocysteine may involve in the pathogenesis of Behcet's disease by inducing inflammation

OBJECTIVE

Our aim was to evaluate the significance of homocysteine (Hcy) in Behcet's disease (BD) and the association of elevated Hcy levels associated with the indices of inflammation in BD.

METHODS

Untreated 70 patients with BD and 33 healthy individuals were included into the study. Hcy, tumor necrosis alpha (TNF-alpha), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were evaluated with respect to activity and specific individual clinical manifestations of the disease.

RESULTS

Hcy levels were found significantly elevated in active BD when compared to inactive BD and healthy controls. Hcy levels were found to have high correlation with the number of active clinical manifestations increased. A significant positive correlation was found between serum Hcy and TNF-alpha levels, CRP, and ESR. Hcy was found to be the best predictor of TNF-alpha among other parameters.

CONCLUSION

Hcy may involve in the pathogenesis of BD by inducing inflammation.

Relationship between thiolactonase activity and hyperhomocysteinemia according to MTHFR gene polymorphism in Tunisian Behçet's disease patients

BACKGROUND

Behçet's disease (BD) is a multisystemic immuno-inflammatory disorder. Inflammatory processes may cause lipid peroxidation, alteration of lipid profile and increase the risk of atherosclerosis. The aim of this study was to evaluate the association between thiolactonase (HTLase) activity and plasma homocysteine levels (tHcy) in a BD population and to investigate their association with methylenetetrahydrofolate reductase (MTHFR) 677C-->T genotype.

METHOD

A total of 35 BD patients were compared to 39 healthy volunteers.

RESULTS

Significantly higher tHcy levels associated with lower HTLase activities were found in BD patients as compared to healthy controls (p<0.001). These patients also exhibited lower values of triglycerides and high-density lipoprotein cholesterol (HDL-C). Homozygosity for the T allele of the MTHFR gene was more frequent in BD patients (14.3% vs. 7.7%). It was associated with significantly higher tHcy levels (16.9 micromol/L for n=17 vs. 13.1 micromol/L for n=18; p<0.05) and markedly lower HTLase activity (362.6+/-156.7 U/L vs. 414.2+/-180.2 U/L) for the (TT+CT) and CC genotypes, respectively. Moreover, HDL-C levels were inversely correlated with tHcy (r=-0.5; p=0.004) but positively associated with HTLase activity (r=0.374; p=0.038). These correlations were also present in several clinical manifestations, such as ocular, neurological involvement or thrombosis.

CONCLUSIONS

Homozygosity of the T allele of the MTHFR gene is prevalent in BD patients. High levels of tHcy associated with low HTLase activities may be one of the causes leading to thrombosis in BD patients.

Behçet's disease

PURPOSE OF REVIEW

To summarize recent scientific developments in the epidemiology, genetics, pathogenesis and treatment of Behçet's disease.

RECENT FINDINGS

Important genetic and immunologic studies were performed. Tumor necrosis factor-alpha-1031C allele was associated with disease susceptibility. Polymorphisms in interleukin-10, IL-8 and CD28 genes were also associated with Behçet's disease. Association with endothelial nitric oxide synthase gene polymorphism was confirmed but was ethnic related. Significant T helper type 1 immune reaction was reconfirmed in recent studies, especially during active phases, but T helper type 2 reaction may also play a role. Interleukin-12B heterozygosity is associated with Behçet's disease susceptibility and plays an important role in mediating T helper type 1 antistreptococcal immune response. Selenium binding protein may be a target antigen in Behçet's uveitis. Pathergy reaction is most frequently positive in the forearm; multiple needle pricks increase positive rate. Experience with anti-tumour necrosis factor therapy for various manifestations is increasing. Cyclosporin A treatment may be associated with new onset of neuro-Behçet. There is a high prevalence of headaches with moderate or severe disability. Cardiac manifestations include left ventricular dysfunction and coronary flow abnormalities. Anti-Saccharomyces cerevisiae antibodies may be especially common in intestinal Behçet's disease and are also increased in healthy relatives of patients.

SUMMARY

Considerable progress has been made, particularly in understanding the immunologic and genetic basis of the disease. The importance of novel serological markers and autoantigens merits further investigations.