SARS-CoV-2 infection in patients with primary Sjögren syndrome: characterization and outcomes of 51 patients.

OBJECTIVE: To analyse the prognosis and outcomes of SARS-CoV-2 infection in patients with primary SS. METHODS: We searched for patients with primary SS presenting with SARS-CoV-2 infection (defined following and according to the European Centre for Disease Prevention and Control guidelines) among those included in the Big Data Sjögren Registry, an international, multicentre registry of patients diagnosed according to the 2002/2016 classification criteria. RESULTS: A total of 51 patients were included in the study (46 women, mean age at diagnosis of infection of 60 years). According to the number of patients with primary SS evaluated in the Registry (n = 8211), the estimated frequency of SARS-CoV-2 infection was 0.62% (95% CI 0.44, 0.80). All but two presented with symptoms suggestive of COVID-19, including fever (82%), cough (57%), dyspnoea (39%), fatigue/myalgias (27%) and diarrhoea (24%), and the most frequent abnormalities included raised lactate dehydrogenase (LDH) (88%), CRP (81%) and D-dimer (82%) values, and lymphopenia (70%). Infection was managed at home in 26 (51%) cases and 25 (49%) required hospitalization (five required admission to ICU, four died). Compared with patients managed at home, those requiring hospitalization had higher odds of having lymphopenia as laboratory abnormality (adjusted OR 21.22, 95% CI 2.39, 524.09). Patients with comorbidities had an older age (adjusted OR 1.05, 95% CI 1.00, 1.11) and showed a risk for hospital admission six times higher than those without (adjusted OR 6.01, 95% CI 1.72, 23.51) in the multivariate analysis. CONCLUSION: Baseline comorbidities were a key risk factor for a more complicated COVID-19 in patients with primary SS, with higher rates of hospitalization and poor outcomes in comparison with patients without comorbidities.

A Genome-wide Association Study Identifies Risk Alleles in Plasminogen and P4HA2 Associated with Giant Cell Arteritis.

Giant cell arteritis (GCA) is the most common form of vasculitis in individuals older than 50 years in Western countries. To shed light onto the genetic background influencing susceptibility for GCA, we performed a genome-wide association screening in a well-powered study cohort. After imputation, 1,844,133 genetic variants were analyzed in 2,134 case subjects and 9,125 unaffected individuals from ten independent populations of European ancestry. Our data confirmed HLA class II as the strongest associated region (independent signals: rs9268905, p = 1.94 × 10-54, per-allele OR = 1.79; and rs9275592, p = 1.14 × 10-40, OR = 2.08). Additionally, PLG and P4HA2 were identified as GCA risk genes at the genome-wide level of significance (rs4252134, p = 1.23 × 10-10, OR = 1.28; and rs128738, p = 4.60 × 10-9, OR = 1.32, respectively). Interestingly, we observed that the association peaks overlapped with different regulatory elements related to cell types and tissues involved in the pathophysiology of GCA. PLG and P4HA2 are involved in vascular remodelling and angiogenesis, suggesting a high relevance of these processes for the pathogenic mechanisms underlying this type of vasculitis.

Epidemiological profile and north-south gradient driving baseline systemic involvement of primary Sjögren's syndrome.

OBJECTIVE: To characterize the systemic phenotype of primary Sjögren's syndrome at diagnosis by analysing the EULAR-SS disease activity index (ESSDAI) scores. METHODS: The Sjögren Big Data Consortium is an international, multicentre registry based on worldwide data-sharing cooperative merging of pre-existing databases from leading centres in clinical research in Sjögren's syndrome from the five continents. RESULTS: The cohort included 10 007 patients (9352 female, mean 53 years) with recorded ESSDAI scores available. At diagnosis, the mean total ESSDAI score was 6.1; 81.8% of patients had systemic activity (ESSDAI score ≥1). Males had a higher mean ESSDAI (8.1 vs 6.0, P < 0.001) compared with females, as did patients diagnosed at <35 years (6.7 vs 5.6 in patients diagnosed at >65 years, P < 0.001). The highest global ESSDAI score was reported in Black/African Americans, followed by White, Asian and Hispanic patients (6.7, 6.5, 5.4 and 4.8, respectively; P < 0.001). The frequency of involvement of each systemic organ also differed between ethnic groups, with Black/African American patients showing the highest frequencies in the lymphadenopathy, articular, peripheral nervous system, CNS and biological domains, White patients in the glandular, cutaneous and muscular domains, Asian patients in the pulmonary, renal and haematological domains and Hispanic patients in the constitutional domain. Systemic activity measured by the ESSDAI, clinical ESSDAI (clinESSDAI) and disease activity states was higher in patients from southern countries (P < 0.001). CONCLUSION: The systemic phenotype of primary Sjögren's syndrome is strongly influenced by personal determinants such as age, gender, ethnicity and place of residence, which are key geoepidemiological players in driving the expression of systemic disease at diagnosis.

Systemic phenotype related to primary Sjögren's syndrome in 279 patients carrying isolated anti-La/SSB antibodies.

OBJECTIVES: To evaluate the systemic phenotype associated with the presence of isolated anti-La/SSB antibodies in a large international registry of patients with primary Sjögren's syndrome (pSS) fulfilling the 2002 classification criteria. METHODS: The Big Data Sjögren Project Consortium is an international, multicentre registry created in 2014. Baseline clinical information from leading centres on clinical research in SS of the 5 continents was collected. Combination patterns of anti-Ro/SSA-La/SSB antibodies at the time of diagnosis defined the following four immunological phenotypes: double positive (combined Ro/SSA and La/SSB,) isolated anti-Ro/SSA, isolated anti-La/SSB, and immunonegative. RESULTS: The cohort included 12,084 patients (11,293 females, mean 52.4 years) with recorded ESSDAI scores available. Among them, 279 (2.3%) had isolated anti-La/SSB antibodies. The mean total ESSDAI score at diagnosis of patients with pSS carrying isolated anti-La/SSB was 6.0, and 80.4% of patients had systemic activity (global ESSDAI score ≥1) at diagnosis. The domains with the highest frequency of active patients were the biological (42.8%), glandular (36.8%) and articular (31.2%) domains. Patients with isolated anti-La/SSB showed a higher frequency of active patients in all ESSDAI domains but two (articular and peripheral nerve) in comparison with immune-negative patients, and even a higher absolute frequency in six clinical ESSDAI domains in comparison with patients with isolated anti-Ro/SSA. In addition, patients with isolated anti-La/SSB showed a higher frequency of active patients in two ESSDAI domains (pulmonary and glandular) with respect to the most active immunological subset (double-positive antibodies). Meanwhile, systemic activity detected in patients with isolated anti-La/SSB was overwhelmingly low. Even in ESSDAI domains where patients with isolated anti-La/SSB had the highest frequencies of systemic activity (lymphadenopathy and muscular), the percentage of patients with moderate or high activity was lower in comparison with the combined Ro/SSA and La/SSB group. CONCLUSIONS: Patients carrying isolated La/SSB antibodies represent a very small subset of patients with a systemic SS phenotype characterised by a significant frequency of active patients in most clinical ESSDAI domains but with a relative low frequency of the highest severe organ-specific involvements. Primary SS still remains the best clinical diagnosis for this subset of patients.

Systemic manifestations of primary Sjögren's syndrome out of the ESSDAI classification: prevalence and clinical relevance in a large international, multi-ethnic cohort of patients.

OBJECTIVES: To analyse the frequency and characterise the systemic presentation of primary Sjögren's syndrome (SS) out of the ESSDAI classification in a large international, multi-ethnic cohort of patients. METHODS: The Big Data Sjögren Project Consortium is an international, multicentre registry based on world-wide data-sharing and cooperative merging of pre-existing clinical SS databases from leading centres in clinical research in SS from the five continents. A list of 26 organ-by-organ systemic features not currently included in the ESSDAI classification was defined according to previous studies; these features were retrospectively recorded. RESULTS: Information about non-ESSDAI features was available in 6331 patients [5,917 female, mean age at diagnosis 52 years, mainly White (86.3%)]. A total of 1641 (26%) patients had at least one of the ESSDAI systemic features. Cardiovascular manifestations were the most frequent organ-specific group of non-ESSDAI features reported in our patients (17% of the total cohort), with Raynaud's phenomenon being reported in 15%. Patients with systemic disease due to non-ESSDAI features had a lower frequency of dry mouth (90.7% vs. 94.1%, p<0.001) and positive minor salivary gland biopsy (86.7% vs. 89%, p=0.033), a higher frequency of anti-Ro/SSA (74.7% vs. 68.7%, p<0.001), anti-La/SSB antibodies (44.5% vs. 40.4%, p=0.004), ANA (82.7% vs. 79.5%, p=0.006), low C3 levels (17.4% vs. 9.7%, p<0.001), low C4 levels (14.4% vs. 9.6%, p<0.001), and positive serum cryoglobulins (8.6% vs. 5.5%, p=0.001). Systemic activity measured by the ESSDAI, clinESSDAI and DAS was higher in patients with systemic disease out of the ESSDAI in comparison with those without these features (p<0.001 for all comparisons). CONCLUSIONS: More than a quarter of patients with primary SS may have systemic manifestations not currently included in the ESSDAI classification, with a wide variety of cardiovascular, digestive, pulmonary, neurological, ocular, ENT (ear, nose, and throat), cutaneous and urological features that increase the scope of the systemic phenotype of the disease. However, the individual frequency of each of these non-ESSDAI features was very low, except for Raynaud's phenomenon.

A large-scale genetic analysis reveals a strong contribution of the HLA class II region to giant cell arteritis susceptibility.

We conducted a large-scale genetic analysis on giant cell arteritis (GCA), a polygenic immune-mediated vasculitis. A case-control cohort, comprising 1,651 case subjects with GCA and 15,306 unrelated control subjects from six different countries of European ancestry, was genotyped by the Immunochip array. We also imputed HLA data with a previously validated imputation method to perform a more comprehensive analysis of this genomic region. The strongest association signals were observed in the HLA region, with rs477515 representing the highest peak (p = 4.05 × 10(-40), OR = 1.73). A multivariate model including class II amino acids of HLA-DRß1 and HLA-DQα1 and one class I amino acid of HLA-B explained most of the HLA association with GCA, consistent with previously reported associations of classical HLA alleles like HLA-DRB1(∗)04. An omnibus test on polymorphic amino acid positions highlighted DRß1 13 (p = 4.08 × 10(-43)) and HLA-DQα1 47 (p = 4.02 × 10(-46)), 56, and 76 (both p = 1.84 × 10(-45)) as relevant positions for disease susceptibility. Outside the HLA region, the most significant loci included PTPN22 (rs2476601, p = 1.73 × 10(-6), OR = 1.38), LRRC32 (rs10160518, p = 4.39 × 10(-6), OR = 1.20), and REL (rs115674477, p = 1.10 × 10(-5), OR = 1.63). Our study provides evidence of a strong contribution of HLA class I and II molecules to susceptibility to GCA. In the non-HLA region, we confirmed a key role for the functional PTPN22 rs2476601 variant and proposed other putative risk loci for GCA involved in Th1, Th17, and Treg cell function.

Venous thrombosis and relapses in patients with Behçet's disease. Descriptive analysis from Spanish network of Behçet's disease (REGEB cohort).

OBJECTIVES: To describe the characteristics of patients with Behçet's disease (BD) who presented with venous thrombosis. In addition, we identified the factors associated with this venous involvement and those related with recurrent venous thrombosis. METHODS: Up to January 2015, 544 BD patients from 20 Spanish hospitals had been included in the REGEB (REGistro de la Enfermedad de Behçet as Spanish nomenclature). We selected those patients who presented venous thrombosis. Descriptive analysis was performed and factors related with venous thrombosis were identified. RESULTS: Overall, 99 (18.2%) BD patients had vascular thrombosis, 91 (16.7%) of them (16.7%) involving venous vessels and 18 (19.7%) suffered from venous thrombotic relapse. Lower limbs were the most common location of deep venous thrombosis present in up to 60% of patients. In 12 (13.2%) patients, venous thrombosis affected two vascular territories simultaneously and in 6 (6.6%) the venous and arterial involvement coincided in time. Overall, at the diagnosis of venous thrombosis, 97.6% of patients presented concomitantly other clinical symptoms attributable to BD. In logistic regression multivariate analysis factors associated to venous thrombosis were male sex (Odds ratio [OR] 4.3, 95% confidence interval [CI] 2.5-7.7), erythema nodosum (OR 2.4, 95%CI 1.4-4.1), fever (OR 2.0, 95%CI 1.1-3.8), and central nervous system (CNS) involvement (OR 2.5, 95%CI 1.3-4.8). Considering relapses, CNS involvement was an independent risk factor according logistic regression. However, Cox multivariate analysis did not confirm this finding. CONCLUSIONS: We identified factors related with venous involvement in patients included in the REGEB cohort.

Severe, life-threatening phenotype of primary Sjögren's syndrome: clinical characterisation and outcomes in 1580 patients (GEAS-SS Registry).

OBJECTIVES: To analyse the clinical features and outcomes of patients presenting with life-threatening systemic disease in a large cohort of Spanish patients with primary Sjögren's syndrome (SS). METHODS: The GEAS-SS multicentre registry was formed in 2005 with the aim of collecting a large series of Spanish patients with primary SS, and included more than 20 Spanish reference centres with substantial experience in the management of SS patients. By January 2018, the database included 1580 consecutive patients fulfilling the 2002 classification criteria for primary SS. Severe, life-threatening systemic disease was defined as an activity level scored as "high" in at least one ESSDAI domain. RESULTS: Among 1580 patients, 208 (13%) were classified as presenting a severe, potentially life-threatening systemic disease: 193 presented one ESSDAI domain classified as high, 14 presented two high scored domains and only one presented three high activity domains. The ESSDAI domains involved consisted of lymphadenopathy in 78 (37%) cases, CNS in 28 (13%), PNS in 25 (12%), pulmonary in 25 (12%), renal in 21 (10%), cutaneous in 19 (9%), articular in 18 (9%), haematological in 7 (3%) and muscular in 4 (2%). Patients with severe systemic disease were more frequently men (p=0.001) and had a higher frequency of anaemia (p<0.001), lymphopenia (p<0.001), rheumatoid factor (p=0.021), low C3 levels (p=0.015), low C4 levels (p<0.001) and cryoglobulins (p<0.001). From a therapeutic point of view, systemic patients received more frequently glucocorticoids (p<0.001), immunosuppressants (p<0.001), intravenous immunoglobulins (p=0.008) and rituximab (p<0.001). We found an overall mortality rate of 20% in severe systemic patients, a rate that reached to 33% in patients presenting two or more high systemic involvements; these patients had a higher frequency of low C4 levels (p=0.012) and cryoglobulins (p=0.001) in comparison with those with a single severe organ involved. CONCLUSIONS: 13% of patients with primary SS develop a potentially life-threatening systemic disease (mainly lymphoma, but also severe internal organ involvements including nervous system, the lungs and the kidneys). This subset of patients requires intensive therapeutic management with a mortality rate of nearly 20% of cases.

How immunological profile drives clinical phenotype of primary Sjögren's syndrome at diagnosis: analysis of 10,500 patients (Sjögren Big Data Project).

OBJECTIVES: To evaluate the influence of the main immunological markers on the disease phenotype at diagnosis in a large international cohort of patients with primary Sjögren's syndrome (SjS). METHODS: The Big Data Sjögren Project Consortium is an international, multicentre registry created in 2014. As a first step, baseline clinical information from leading centres on clinical research in SjS of the 5 continents was collected. The centres shared a harmonised data architecture and conducted cooperative online efforts in order to refine collected data under the coordination of a big data statistical team. Inclusion criteria were the fulfillment of the 2002 classification criteria. Immunological tests were carried out using standard commercial assays. RESULTS: By January 2018, the participant centres had included 10,500 valid patients from 22 countries. The cohort included 9,806 (93%) women and 694 (7%) men, with a mean age at diagnosis of primary SjS of 53 years, mainly White (78%) and included from European countries (71%). The frequency of positive immunological markers at diagnosis was 79.3% for ANA, 73.2% for anti-Ro, 48.6% for RF, 45.1% for anti- La, 13.4% for low C3 levels, 14.5% for low C4 levels and 7.3% for cryoglobulins. Positive autoantibodies (ANA, Ro, La) correlated with a positive result in salivary gland biopsy, while hypocomplementaemia and especially cryoglo-bulinaemia correlated with systemic activity (mean ESSDAI score of 17.7 for cryoglobulins, 11.3 for low C3 and 9.2 for low C4, in comparison with 3.8 for negative markers). The immunological markers with a great number of statistically-significant associations (p<0.001) in the organ-by-organ ESS- DAI evaluation were cryoglobulins (9 domains), low C3 (8 domains), anti-La (7 domains) and low C4 (6 domains). CONCLUSIONS: We confirm the strong influence of immunological markers on the phenotype of primary SjS at diagnosis in the largest multi-ethnic international cohort ever analysed, with a greater influence for cryoglobulinaemic-related markers in comparison with Ro/La autoantibodies and ANA. Immunological patterns play a central role in the phenotypic expression of the disease already at the time of diagnosis, and may guide physicians to design a specific personalised management during the follow-up of patients with primary SjS.

Influence of geolocation and ethnicity on the phenotypic expression of primary Sjögren's syndrome at diagnosis in 8310 patients: a cross-sectional study from the Big Data Sjögren Project Consortium.

OBJECTIVES: To analyse the influence of geolocation and ethnicity on the clinical presentation of primary Sjögren's syndrome (SjS) at diagnosis. METHODS: The Big Data Sjögren Project Consortium is an international, multicentre registry designed in 2014. By January 2016, 20 centres from five continents were participating. Multivariable logistic regression analyses were performed. RESULTS: We included 7748 women (93%) and 562 men (7%), with a mean age at diagnosis of primary SjS of 53 years. Ethnicity data were available for 7884 patients (95%): 6174 patients (78%) were white, 1066 patients (14%) were Asian, 393 patients (5%) were Hispanic, 104 patients (1%) were black/African-American and 147 patients (2%) were of other ethnicities. SjS was diagnosed a mean of 7 years earlier in black/African-American compared with white patients; the female-to-male ratio was highest in Asian patients (27:1) and lowest in black/African-American patients (7:1); the prevalence of sicca symptoms was lowest in Asian patients; a higher frequency of positive salivary biopsy was found in Hispanic and white patients. A north-south gradient was found with respect to a lower frequency of ocular involvement in northern countries for dry eyes and abnormal ocular tests in Europe (OR 0.46 and 0.44, respectively) and Asia (OR 0.18 and 0.49, respectively) compared with southern countries. Higher frequencies of antinuclear antibodies (ANAs) were reported in northern countries in America (OR=1.48) and Asia (OR=3.80) while, in Europe, northern countries had lowest frequencies of ANAs (OR=0.67) and Ro/La (OR=0.69). CONCLUSIONS: This study provides the first evidence of a strong influence of geolocation and ethnicity on the phenotype of primary SjS at diagnosis.

PTPN22 is not associated with Behçet's disease. Study spanning the complete gene region in the Spanish population and meta-analysis of the functional variant R620W.

OBJECTIVES: The functional variant R620W of the protein tyrosine phosphatase non receptor-22 (PTPN22) gene plays an important role in susceptibility to several immuno-mediated pathologies. Behçet's disease (BD) is a complex disease related to the immune system with a demonstrated genetic base. The HLA class I genes are the most important genetic factors in BD although other genes are also involved in the susceptibility to this disease. The PTPN22 has been proposed as a candidate gene in BD but this association has not been clearly demonstrated yet. The aim of this study was to assess the association of PTPN22 with BD. METHODS: A cohort composed of 404 Spanish BD patients and 1517 unrelated healthy individuals ethnically matched was genotyped in rs2476601 (R620W). Five tag SNPs: rs1217412, rs2476599, rs3789607, rs3765598 and rs1217419 (spanning a 57 Kb region between 3'UTR and 5'UTR) and rs2488457 (located at the promoter region) were also studied in order to perform a screening of the complete gene. Genotyping was performed using TaqMan® assays. The rs2476601 data were included in a meta-analysis together with those published till the date. The rest of SNPs were used in a case-control study. RESULTS: No evidence of the association of rs2476601 with BD in the meta-analysis (P = 0.504 in the model of alleles) was found. In the case-control study, no statistically significant differences were observed when comparing the distribution of variants in patients and controls. CONCLUSIONS: Our results do not support a major role of the PTPN22 gene in BD.

Central nervous system involvement of granulomatosis with polyangiitis: clinical-radiological presentation distinguishes different outcomes.

OBJECTIVE: The aim of this study was to describe the presentation and outcomes of patients with granulomatosis with polyangiitis (GPA) presenting with CNS involvement. METHODS: Patients were included in this nationwide retrospective study if they had GPA according to ACR criteria and/or the European Medicines Agency algorithm and CNS involvement. RESULTS: Thirty-five patients were included in the study. CNS involvement was observed in 51% of patients at GPA diagnosis. Headache (66%) was the main symptom, followed by sensory (43%) and motor impairment (31%). CNS involvement was characterized by pachymeningitis in 20, cerebral ischaemic lesions in 15 and haemorrhagic lesions in 2, with hypophyseal involvement in 2 patients. According to the clinical-radiological presentation, we distinguished granulomatous (G-CNS) and vasculitic (V-CNS) phenotypes. G-CNS patients more frequently had headaches, while V-CNS patients more frequently had motor impairment and renal involvement. Induction therapy produced clinical responses in 86% of patients. Baseline modified Rankin scale was higher for V-CNS than G-CNS patients (3 vs 2, P = 0.002). Initial spinal cord pachymeningitis was significantly associated with the need for a new induction regimen for relapsing/refractory disease (P = 0.01). Long-term neurological sequelae were noted in 51% of patients, including 35% with G-CNS and 69% with V-CNS (P = 0.08). Neurological sequelae were mainly noted in cases of spinal cord pachymeningitis (100%) and ischaemic or haemorrhagic lesions (73%). CONCLUSION: The clinical-radiological phenotype distinguished different long-term outcomes in patients with GPA and CNS involvement. Long-term neurological sequelae persisted in half of patients, mainly those with spinal cord pachymeningitis and vasculitic lesions.

Association of CCR5Δ32 and Behçet's disease: new data from a case-control study in the Spanish population and meta-analysis.

OBJECTIVES: Behçet's disease (BD) is an immune-mediated and complex disease associated with HLA class I and other genes. The aim of this study was to contribute to a better understanding of the relationship of the 32-bp deletion in the CCR5 gene (CCR5Δ32) and this disease by conducting a case-control study in the Spanish population and also a meta-analysis including all the studies available to date. METHODS: A cohort composed of 348 BD Spanish patients and 477 unrelated healthy and ethnically matched individuals were genotyped in CCR5Δ32 using polymerase chain reaction (PCR) and capillary electrophoresis with fluorescent detection. In the meta-analysis, data from a total of seven populations extracted from four previous studies along with data of the present study were included. RESULTS: Regarding the case-control study, no statistically significant differences were observed when the patient and control groups were compared (allelic model: 0.07 in patients vs. 0.06 in controls, p=0.303). In the meta-analysis, no evidence of association of the CCR5Δ32 polymorphism with BD was observed (pMH=0.091; OR=1.22; 95%CI 0.98 to 1.52 in the allelic model). CONCLUSIONS: The results of this meta-analysis discard a major role of the CCR5Δ32 polymorphism in BD.

Association of haplotypes of the TLR8 locus with susceptibility to Crohn's and Behçet's diseases.

OBJECTIVES: The aim of this study was to investigate the role of the TLR8, a mediator of innate inflammatory response, in susceptibility to two immune-mediated disorders characterised by dysregulation of the immune response, Crohn's and Behçet's diseases (CD and BD). METHODS: A total of 844 CD, 371 BD patients and 1385 controls were genotyped in 8 tag single nucleotide polymorphisms (tSNPs) in the locus TLR8 (chromosome X). All these tSNPs have a minor allele frequency greater than 0.05 in the Caucasian population. RESULTS: The rs2407992 and the rs5744067 were associated with susceptibility to BD and CD, respectively (OR=1.34, 95%CI=1.10-1.62, p=0.0025 and OR=0.82, 95%CI=0.68-0.99, p=0.045, respectively). Although after stratification by gender, statistically significant differences in the distribution of the aforementioned SNPs were only observed in the females groups (BD OR=1.31, 95%CI=1.06-1.64, p=0.012 and CD OR=0.84, 95%CI=0.72-0.98, p=0.044) the trend was similar among males. Since the rs5744067 and rs2407992 are located in the same linkage disequilibrium block, we performed a haplotypic analysis by combination of the tSNPs. One haplotype (H1) was identified as a protective factor in BD (OR=0.75, 95%CI=0.62-0.90, p=0.0027) and another (H2) as a protective factor in CD (OR=0.78, 95%CI=0.64-094, p=0.0102). No statistically significant differences in the mean of the levels of expression attributable to the haplotype variants were found in the in silico analysis performed. CONCLUSIONS: Our results suggest a relationship between the TLR8 and the susceptibility to CD and BD. Nevertheless, these differences could not be imputed to the levels of expression.

Lack of association of TNFAIP3 and JAK1 with Behçet's disease in the European population.

OBJECTIVES: Behçet's disease (BD) is an immune-mediated and complex disease which has been associated with HLA class I molecules although other genes such as IL23R and IL10 have also been involved in the susceptibility to BD. Recently, an association of variants of the JAK1 and TNFAIP3 genes with the disease has been reported in the Chinese Han population. The aim of the present work was to asses whether the association described in Asian populations is replicated in Europeans. METHODS: This study includes a total of 1155 Spanish subjects of European origin (372 BD and 783 unrelated healthy individuals). Patients were recruited from different hospitals and controls were collected in the same geographic regions and they matched with patients in age and gender. A total of five SNPs, two in the JAK1 gene: rs2780815 and rs310241 and the other three in the TNFAIP3: rs10499194, rs9494885 and rs610604, were included in this study. The genotyping of these SNPs was performed using a real time PCR system (TaqMan® SNP Genotyping Assays). RESULTS: No statistically significant differences were found when the patient and control groups were compared. The distribution of the risk alleles was similar in patients with and without eye manifestations and in patients with and without HLA-B*51. CONCLUSIONS: The association of variants of the genes JAK1 and the TNFAIP3 with BD which has been described in the Chinese population was not replicated in Europeans.

Systemic involvement in primary Sjogren's syndrome evaluated by the EULAR-SS disease activity index: analysis of 921 Spanish patients (GEAS-SS Registry).

OBJECTIVE: To evaluate systemic involvement in primary SS in a large cohort of Spanish patients using the EULAR-SS disease activity index (ESSDAI) definitions. METHODS: Systemic involvement was characterized using ESSDAI definitions for the 10 clinical domains (constitutional, lymphadenopathy, glandular, articular, cutaneous, pulmonary, renal, peripheral nervous system, central nervous system and muscular). ESSDAI scores at diagnosis, during follow-up and cumulated at the last visit were calculated. RESULTS: The cohort consisted of 921 patients. After a mean follow-up of 75 months, 77 (8%) patients still had an ESSDAI score of zero at the last visit. Organ by organ, the percentage of patients who developed activity during the follow-up (ESSDAI score ≥ 1 at any time) ranged between 1.4% and 56%, with articular, pulmonary and peripheral neurological involvement being the most common. Logistic multivariate regression analysis showed the following features at diagnosis and had the closest association with systemic activity (statistically significant independent variables in at least two domains): cryoglobulinaemia in five domains; anaemia, lymphopenia and low C3 levels in three domains each and age <35 years in two domains. Sicca features, ANA and RF at diagnosis were not associated with a higher cumulated activity score in any clinical domain. CONCLUSION: Primary SS is undeniably a systemic disease, with the joints, lungs, skin and peripheral nerves being the most frequently involved organs. Cytopenias, hypocomplementaemia and cryoglobulinaemia at diagnosis strongly correlated with higher cumulated ESSDAI scores in the clinical domains. Clinically the ESSDAI provides a reliable picture of systemic involvement in primary SS.

Analysis of two autoimmunity genes, IRAK1 and MECP2, in giant cell arteritis.

OBJECTIVES: The Xq28 region, containing IRAK and MECP2, represent a common susceptibility locus for a high number of autoimmune diseases. Our aim in the present study was to evaluate the influence of the IRAK1 and MECP2 autoimmunity-associated genetic variants in the giant cell arteritis (GCA) susceptibility and its clinical subphenotypes. METHODS: We analysed a total of 627 female biopsy-proven GCA patients and 1,520 female healthy controls of Spanish Caucasian origin. Two polymorphisms, rs1059702 and rs17345, located at IRAK1 and MECP2, respectively, were genotyped using TaqMan® allelic discrimination assays. RESULTS: No association with any of the analysed polymorphisms was evident when genotype and allele frequencies were compared between GCA patients and controls (rs1059702: allelic p-value=0.699, OR=0.96, CI 95% 0.80-1.17; rs17435: allelic p-value=0.994, OR=1.00, CI 95% 0.84-1.19). Likewise, the subphenotype analysis yield similar negative results. CONCLUSIONS: We have assessed for the first time the possible role of IRAK1 and MECP2 autoimmune disease-associated polymorphisms in GCA. Our data suggest that IRAK1 rs1059702 and MECP2 rs17435 genetic variants do not play a significant role in GCA susceptibility or severity.

Risk loci involved in giant cell arteritis susceptibility: a genome-wide association study.

BACKGROUND: Giant cell arteritis is an age-related vasculitis that mainly affects the aorta and its branches in individuals aged 50 years and older. Current options for diagnosis and treatment are scarce, highlighting the need to better understand its underlying pathogenesis. Genome-wide association studies (GWAS) have emerged as a powerful tool for unravelling the pathogenic mechanisms involved in complex diseases. We aimed to characterise the genetic basis of giant cell arteritis by performing the largest GWAS of this vasculitis to date and to assess the functional consequences and clinical implications of identified risk loci. METHODS: We collected and meta-analysed genomic data from patients with giant cell arteritis and healthy controls of European ancestry from ten cohorts across Europe and North America. Eligible patients required confirmation of giant cell arteritis diagnosis by positive temporal artery biopsy, positive temporal artery doppler ultrasonography, or imaging techniques confirming large-vessel vasculitis. We assessed the functional consequences of loci associated with giant cell arteritis using cell enrichment analysis, fine-mapping, and causal gene prioritisation. We also performed a drug repurposing analysis and developed a polygenic risk score to explore the clinical implications of our findings. FINDINGS: We included a total of 3498 patients with giant cell arteritis and 15 550 controls. We identified three novel loci associated with risk of giant cell arteritis. Two loci, MFGE8 (rs8029053; p=4·96 × 10-8; OR 1·19 [95% CI 1·12-1·26]) and VTN (rs704; p=2·75 × 10-9; OR 0·84 [0·79-0·89]), were related to angiogenesis pathways and the third locus, CCDC25 (rs11782624; p=1·28 × 10-8; OR 1·18 [1·12-1·25]), was related to neutrophil extracellular traps (NETs). We also found an association between this vasculitis and HLA region and PLG. Variants associated with giant cell arteritis seemed to fulfil a specific regulatory role in crucial immune cell types. Furthermore, we identified several drugs that could represent promising candidates for treatment of this disease. The polygenic risk score model was able to identify individuals at increased risk of developing giant cell arteritis (90th percentile OR 2·87 [95% CI 2·15-3·82]; p=1·73 × 10-13). INTERPRETATION: We have found several additional loci associated with giant cell arteritis, highlighting the crucial role of angiogenesis in disease susceptibility. Our study represents a step forward in the translation of genomic findings to clinical practice in giant cell arteritis, proposing new treatments and a method to measure genetic predisposition to this vasculitis. FUNDING: Institute of Health Carlos III, Spanish Ministry of Science and Innovation, UK Medical Research Council, and National Institute for Health and Care Research.

The complex HLA-E-nonapeptide in Behçet disease.

Introduction: The knowledge of the aetiology of Behçet disease (BD), an immune-mediated vasculitis, is limited. HLA-B, mainly HLA-B51, and HLA-A molecules are associated with disease, but the ultimate cause of this association remains obscure. There is evidence that NK cells participate in the etiopathology of BD. NK cells have activator and inhibitor surface receptors, like the KIR and the NKG2 families. Classical HLA-class I molecules (A, B and C) are keys in the activity control of the NK because they are KIR ligands. Most NKG2 receptors bind HLA-E, which presents only nonapeptides derived from the signal peptide of other class-I molecules. Objective: This study investigates the contribution of the pair HLA-E and ligand, nonapeptide derived from the 3-11 sequence of the signal peptides of class I classical molecules, to the susceptibility to BD. Methods: We analyzed the frequency of the HLA-derivated nonapeptide forms in 466 BD patients and 444 controls and an HLA-E functional dimorphism in a subgroup of patients and controls. Results: In B51 negative patients, the frequency of VMAPRTLLL was lower (70.4% versus 80.0% in controls; P=0.006, Pc=0.04, OR=0.60, 95%CI 0.41-0.86), and the frequency of VMAPRTLVL was higher (81.6% versus 71.4% in controls; P=0.004, Pc=0.03, OR=1.78, 95%CI 1.20-2.63). In homozygosity, VMAPRTLLL is protective, and VMAPRTLVL confers risk. The heterozygous condition is neutral. There were no significant differences in the distribution of the HLA-E dimorphism. Discussion: Our results explain the association of BD with diverse HLA-A molecules, reinforce the hypothesis of the involvement of the NK cells in the disease and do not suggest a significant contribution of the HLA-E polymorphism to disease susceptibility.