Emire Seyahi

Genome-wide association analysis identifies new susceptibility loci for Behcet's disease and epistasis between HLA-B*51 and ERAP1.

Individuals with Behçets disease suffer from episodic inflammation often affecting the orogenital mucosa, skin and eyes. To discover new susceptibility loci for Behçets disease, we performed a genome-wide association study (GWAS) of 779,465 SNPs with imputed genotypes in 1,209 Turkish individuals with Behçets disease and 1,278 controls. We identified new associations at CCR1, STAT4 and KLRC4. Additionally, two SNPs in ERAP1, encoding ERAP1 p.Asp575Asn and p.Arg725Gln alterations, recessively conferred disease risk. These findings were replicated in 1,468 independent Turkish and/or 1,352 Japanese samples (combined meta-analysis P < 2 × 10−9). We also found evidence for interaction between HLA-B*51 and ERAP1 (P = 9 × 10−4). The CCR1 and STAT4 variants were associated with gene expression differences. Three risk loci shared with ankylosing spondylitis and psoriasis (the MHC class I region, ERAP1 and IL23R and the MHC class I–ERAP1 interaction), as well as two loci shared with inflammatory bowel disease (IL23R and IL10) implicate shared pathogenic pathways in the spondyloarthritides and Behçets disease.

Identification of multiple genetic susceptibility loci in Takayasu arteritis

Takayasu arteritis is a rare inflammatory disease of large arteries. The etiology of Takayasu arteritis remains poorly understood, but genetic contribution to the disease pathogenesis is supported by the genetic association with HLA-B*52. We genotyped ~200,000 genetic variants in two ethnically divergent Takayasu arteritis cohorts from Turkey and North America by using a custom-designed genotyping platform (Immunochip). Additional genetic variants and the classical HLA alleles were imputed and analyzed. We identified and confirmed two independent susceptibility loci within the HLA region (r(2) < 0.2): HLA-B/MICA (rs12524487, OR = 3.29, p = 5.57 × 10(-16)) and HLA-DQB1/HLA-DRB1 (rs113452171, OR = 2.34, p = 3.74 × 10(-9); and rs189754752, OR = 2.47, p = 4.22 × 10(-9)). In addition, we identified and confirmed a genetic association between Takayasu arteritis and the FCGR2A/FCGR3A locus on chromosome 1 (rs10919543, OR = 1.81, p = 5.89 × 10(-12)). The risk allele in this locus results in increased mRNA expression of FCGR2A. We also established the genetic association between IL12B and Takayasu arteritis (rs56167332, OR = 1.54, p = 2.18 × 10(-8)).

Pulmonary Artery Involvement and Associated Lung Disease in Behçet Disease: A Series of 47 Patients

AbstractPulmonary artery aneurysms (PAAs) are well known causes of mortality and morbidity in Behçet disease (BD). However, pulmonary artery involvement in BD is not limited to PAA; the other main type of pulmonary artery involvement is pulmonary artery thrombus (PAT), with or without associated PAA. In addition, other types of lung disease like nodules and cavities in the lung parenchyma are frequently associated with pulmonary artery involvement, and can be misinterpreted as being due to infection. We surveyed the clinical, radiologic, and laboratory characteristics and outcome of 47 BD patients with pulmonary artery involvement and the associated findings, all seen and followed at a single dedicated tertiary care center.We identified 47 (41 male, 6 female) patients in whom pulmonary artery involvement was diagnosed, who were registered in the multidisciplinary clinic at Cerrahpasa Medical Faculty between January 2000 and December 2007. Mean age at diagnosis was 29 ± 8 years, and mean disease duration to the onset of pulmonary artery involvement was 3.6 ± 4.8 years. Hemoptysis was the most common presenting symptom (79%) followed by cough, fever, dyspnea, and pleuritic chest pain. Thirty-four of 47 patients (72%) presented with PAA, including 8 with associated PAT. The remaining 13 patients (28%) had isolated PAT. Patients with isolated PAT in general have clinical features similar to patients with PAA. However, hemoptysis was less frequent and voluminous in patients with isolated PAT. Most (91%) of the patients had active disease outside the lungs when they presented with pulmonary artery involvement.Forty (85%) patients had nodules and 6 (13%) had cavities when first seen. Peripheral venous thrombosis was present in 36 of 47 (77%) patients, and intracardiac thrombi in 12 of the 36 (33%) patients. Nodules, cavities, and intracardiac thrombi were mainly present in the acute stages of pulmonary artery involvement.Pulmonary artery involvement is usually multiple, and involves mostly descending branches of the pulmonary artery. Pulmonary artery involvement may disappear, but arterial stenosis or occlusions usually develop at the same location. After a mean follow-up of 7 years, 12 of 47 (26%) patients were dead; patients with larger aneurysms were more likely to die. Sixteen of 47 (34%) patients were symptom free, and the remaining 40% had mild dyspnea (13/47) and/or small bouts of hemoptysis (8/47).Pulmonary artery pressure may be elevated, and may indicate a poor prognosis. Mediastinal lymphadenopathy and mild pleural and pericardial effusions may also be observed. Corticosteroids and immunosuppressive agents are the mainstays of treatment; however, refractory cases may require embolization, lobectomy, cavitectomy, and decortication.

Canakinumab in a patient with juvenile Behçet's syndrome with refractory eye disease

Behcets syndrome (BS) causes panuveitis and retinal vasculitis in about 50% of patients. Despite intensive treatment, up to 20% of patients may lose useful vision.1 Treatment consists of corticosteroids, immunosuppressive agents such as azathioprine (AZA) and ciclosporin A (CycA),1 and biological agents such as interferon-α (IFN) and antitumour necrosis factor agents.2 ,3 We describe a patient with juvenile BS whose refractory eye disease was treated successfully with canakinumab, a fully human anti-interleukin-1β antibody. Figure 1 shows the different treatment regimes used during the follow-up period. Figure 1 Different treatment regimes and eye flares during the follow-up period. A 16-year-old girl was diagnosed with BS at the age of 9 years because …

Targeted resequencing implicates the familial Mediterranean fever gene MEFV and the toll-like receptor 4 gene TLR4 in Behçet disease

Genome-wide association studies (GWAS) are a powerful means of identifying genes with disease-associated common variants, but they are not well-suited to detecting genes with disease-associated rare and low-frequency variants. In the current study of Behçet disease (BD), nonsynonymous variants (NSVs) identified by deep exonic resequencing of 10 genes found by GWAS (IL10, IL23R, CCR1, STAT4, KLRK1, KLRC1, KLRC2, KLRC3, KLRC4, and ERAP1) and 11 genes selected for their role in innate immunity (IL1B, IL1R1, IL1RN, NLRP3, MEFV, TNFRSF1A, PSTPIP1, CASP1, PYCARD, NOD2, and TLR4) were evaluated for BD association. A differential distribution of the rare and low-frequency NSVs of a gene in 2,461 BD cases compared with 2,458 controls indicated their collective association with disease. By stringent criteria requiring at least a single burden test with study-wide significance and a corroborating test with at least nominal significance, rare and low-frequency NSVs in one GWAS-identified gene, IL23R (P = 6.9 × 10−5), and one gene involved in innate immunity, TLR4 (P = 8.0 × 10−4), were associated with BD. In addition, damaging or rare damaging NOD2 variants were nominally significant across all three burden tests applied (P = 0.0063–0.045). Furthermore, carriage of the familial Mediterranean fever gene (MEFV) mutation Met694Val, which is known to cause recessively inherited familial Mediterranean fever, conferred BD risk in the Turkish population (OR, 2.65; P = 1.8 × 10−12). The disease-associated NSVs in MEFV and TLR4 implicate innate immune and bacterial sensing mechanisms in BD pathogenesis.

Headache in Behçet's Syndrome

Objective.—To study the frequencies and characteristics of different headache types seen in patients with Behçets syndrome (BS) in a large cohort of patients.

Atherosclerosis in Behçet's Syndrome

OBJECTIVES We had the impression and preliminary evidence that atherosclerosis was not much increased in Behçets syndrome (BS). Thus, we evaluated the presence of subclinical atherosclerosis in a sizeable group of patients with BS both with major organ involvement and mucocutaneous disease along with diseased and healthy controls. METHODS We studied 239 (162 M/ 77 F; mean age: 40.7+/-7.0) patients with BS. Seventy-two (32 M/ 40 F) had only mucocutaneous and/or joint disease and 167 (130 M/ 37 F) had major organ involvement. Also 100 (24 M/ 76 F; mean age: 44.7+/-7.1) patients with rheumatoid arthritis (RA), 74 (58 M/ 16 F; mean age: 39.4+/-7.0) patients with ankylosing spondylitis (AS) and 156 (83 M/ 73 F; mean age: 39.2+/-6.6) healthy controls (HC) were studied as the control groups. We used B-mode USG to assess the frequency of plaques and intima-media thickness (IMT) in the carotid and femoral arteries. Traditional atherosclerotic risk factors were also evaluated. Men and women were analyzed separately. RESULTS The frequency of plaques and the mean IMT in the carotid and femoral arteries were similar between patients with BS, AS and HC and also between the 2 subgroups of BS, among both men and women. Only men with RA were found to have significantly increased frequency of carotid artery plaques after adjustment for atherosclerotic risk factors. CONCLUSION Increased atherosclerosis is not a prominent feature of BS, even among those patients with major organ involvement.

Behçet Syndrome: Is It One Condition?

Behçets syndrome (BS) is a disease of unknown etiology, and as such, there have been efforts to classify BS within the popular nosological identities of the times such as seronegative spondarthritides, autoimmune, and more recently autoinflammatory diseases. Current evidence suggests that BS does not easily fit into any one of these lumps, while on occasion, it might be impossible to tell BS from Crohns disease, especially when the main clinical presentation is intestinal ulceration. There are distinct regional differences in disease expression of BS with fewer cases of intestinal disease in the Mediterranean basin and less severe eye disease and less frequent skin pathergy among patients reported from northern Europe or America. The clustering of symptoms, especially with the recently described increased frequency of the acne/arthritis cluster in familial cases, suggests that more than one pathological pathway is involved in what we call BS today. Supportive evidence for this contention also comes from the observations that (a) the genetic component is very complex with perhaps different genetic modes of inheritance in the adult and in the pediatric patients; and (b) there are differing organ responses to one same drug. For example, the anti-TNF agents successfully control the oral ulcers while they have no effect on the pathergy reaction.

Takayasu's arteritis is associated with HLA-B*52, but not with HLA-B*51, in Turkey

IntroductionHLA-B*51 and HLA-B*52 are two close human leukocyte antigen (HLA) allele groups with minor amino acid differences. However, they are associated with two different vasculitides (HLA-B*51 in Behçets disease and HLA-B*52 in Takayasus arteritis (TAK)) and with major clinical and immunological differences. In this study, we aimed to screen a large cohort of TAK patients from Turkey for the presence of HLA-B*51 and HLA-B*52 as susceptibility and severity factors.MethodsTAK patients (n = 330) followed at a total of 15 centers were included in the study. The mean age of the patients was 37.8 years, and 86% were women. DNA samples from the patients and healthy controls (HC; n = 210) were isolated, and the presence of HLA-B*51 or HLA-B*52 was screened for by using PCR with sequence-specific primers.ResultsWe found a significant association of HLA-B*52 with TAK (20.9% vs HC = 6.7%, P = 0.000, OR = 3.7, 95% CI = 2.02 to 6.77). The distribution of HLA-B*51 did not differ between TAK patients and HCs (22.7% vs 24.8%, OR = 0.9, 95% CI = 0.60 to 1.34). The presence of HLA-B*52 decreased in late-onset patients (> 40 years of age; 12.0%, P = 0.024, OR = 0.43, 95% CI = 0.20 to 0.91). Patients with angiographic type I disease with limited aortic involvement also had a lower presence of HLA-B*52 compared to those with all other disease subtypes (13.1% vs 26%, P = 0.005, OR = 0.43, 95% CI = 0.23 to 0.78).ConclusionsIn this study, the previously reported association of TAK with HLA-B*52 in other populations was confirmed in patients from Turkey. The functional relevance of HLA-B*52 in TAK pathogenesis needs to be explored further.

Management and prognosis of nonpulmonary large arterial disease in patients with Behçet disease

OBJECTIVE The purpose of this study was to evaluate and report our treatment policies in the management of nonpulmonary arterial aneurysms in Behçet disease and to assess the prognosis in a cohort of 25 patients diagnosed between 1996 and 2007 by formally reassessing their outcome at the present time. METHODS We identified 25 patients (24 men/1 woman) with Behçet disease with nonpulmonary aneurysms (n = 23) or occlusions (n = 2) between 1996 and 2007. All patients fulfilled the International Study Group Criteria for Behçet disease. Aneurysms were demonstrated with contrast-enhanced computed tomography (CT) or magnetic resonance angiography (MRA) after first-line ultrasonography. Standard surgical procedures were carried out in 22 patients. One patient with a nonruptured saccular aortic aneurysm and 2 patients with carotid aneurysms were managed only medically. For the patients with aneurysms located in the aortic bifurcation, we preferred aorto-bi-iliac bypasses; for the six extremity aneurysms, we were able to ligate the arteries; and for the other 10 extremity aneurysms we used polytetrafluoroethylene (PTFE) grafts for bypass procedures. All patients received immunosuppression with cyclophosphamide and corticosteroids before the operation and were continued in the postoperative period. All patients were examined between January and December 2010 paying special attention for new and anastomotic aneurysms and graft patency. RESULTS There was one death and 1 patient was lost to follow-up. The remaining 23 patients (92%) were under follow-up after a mean of 7.4 ± 2.9 years after their operation. Four PTFE grafts (40%) inserted for extremity aneurysms occluded with no disabling consequences. Also, 6 patients who were treated with ligation postoperatively began to complain of mild to moderate claudication. In 2 patients, aneurysms recurred at the anastomotic site, whereas in 3 patients, new aneurysms developed at other sites. CONCLUSION The surgical management of large, nonpulmonary arterial disease of Behçet disease is currently quite satisfactory. When the false aneurysm is in the infrarenal aorta, aorto-bi-iliac bypass is the preferred surgical intervention. Extremity aneurysms can be treated with synthetic graft insertion. In selected cases, ligation can give satisfactory results; however, postoperative claudication is common. In some patients with small intact saccular aneurysms, surgery may not be necessary. Patients must be prescribed immunosuppressive therapy with cyclophosphamide and corticosteroids before and after the surgical intervention in order to avoid Behçet disease activation.