History of pre-eclampsia does not appear to be a risk factor for vascular phenotype in women with systemic sclerosis

BACKGROUND

Vascular phenotype is associated with a poor prognosis in systemic sclerosis (SSc). The identification of its risk factors could facilitate its early detection.

OBJECTIVES

To explore risk factors for a vascular phenotype of SSc, among them a history of pre-eclampsia.

METHODS

This observational multicentre case-control study enrolled adult women fulfilling European Alliance of Associations for Rheumatology 2013 diagnosis criteria for SSc and having a pregnancy history≥6 months before SSc diagnosis in 14 French hospital-based recruiting centres from July 2020 to July 2022. Cases had specific vascular complications of SSc defined as history of digital ischaemic ulcers, pulmonary arterial hypertension, specific cardiac involvement or renal crisis. Women with SSc were included during their annual follow-up visit and filled in a self-administered questionnaire about pregnancy. A case report form was completed by their physician, reporting data on medical history, physical examination, clinical investigations and current medication. The main outcome was the presence/absence of a personal history of pre-eclampsia before SSc diagnosis, according to the validated pre-eclampsia questionnaire.

RESULTS

378 women were included: 129 cases with a vascular phenotype and 249 matched controls. A history of pre-eclampsia was reported in 5 (3.9%) cases and 12 (4.8%) controls and was not associated with a vascular phenotype (OR=0.96, 95% CI 0.28 to 3.34, p=0.9). Besides, Rodnan skin score and disease duration≥5 years were risk factors for vascular phenotype.

CONCLUSIONS

In women with SSc and a pregnancy history≥6 months before SSc, a history of pre-eclampsia is not associated with a vascular phenotype.

Benralizumab for eosinophilic granulomatosis with polyangiitis

BACKGROUND

Benralizumab is effective in the treatment of eosinophilic asthma and is being investigated for the treatment of other eosinophil-associated diseases. Reports on the use of benralizumab for the treatment of eosinophilic granulomatosis with polyangiitis (EGPA) are limited to case reports and small case series.

METHODS

We conducted a multicentre, retrospective study including EGPA patients treated with off-label benralizumab. The primary endpoint was the rate of complete response defined as no disease activity (Birmingham Vasculitis Activity Score=0) and a prednisone dose ≤4 mg/day. Partial response was defined as no disease activity and a prednisone dose ≥4 mg/day.

RESULTS

Sixty-eight patients were included, including 31 (46%) who had previously received mepolizumab. The use of benralizumab was warranted by uncontrolled asthma in 54 (81%), persistent ear, nose and throat (ENT) manifestations in 27 (40%) and persistent glucocorticoids (GCs) use in 48 (74%) patients. Median (IQR) follow-up after starting benralizumab was 23 (9-34) months. Thirty-three patients (49%) achieved a complete response, 24 (36%) achieved a partial response and 10 (15%) did not respond. Among the 57 patients who initially responded, 10 (18%) eventually required further line treatments. GCs were discontinued in 23 patients (38%). Prior mepolizumab use was associated with a higher rate of primary failure (26.7% vs 5.4%, p=0.034) and less frequent GCs discontinuation (14.8% vs 55.9%, p=0.001). Vasculitis flares occurred in 7 patients (11%) and were associated with histological evidence of vasculitis and/or antineutrophil cytoplasmic antibodies positivity at benralizumab initiation (p=0.004).

CONCLUSIONS

Benralizumab appears to be an effective treatment for refractory asthma or ENT manifestations in EGPA and allows GC-sparing. However, its efficacy was lower after prior failure of mepolizumab.

Stratégies innovantes de vaccination anti-pneumococcique par rapport au schéma standard chez les patients atteints de vascularites associées aux ANCA recevant du rituximab : essai contrôlé randomisé multicentrique (PNEUMOVAS)

Introduction

Les patients recevant des glucocorticoïdes et du rituximab (RTX) présentent un risque accru d’infections, en particulier d’infections invasives à pneumocoque. Les réponses vaccinales au virus de la grippe, au Streptococcus pneumoniae et au SARS-CoV-2 sous traitement par RTX sont fortement altérées. Chez les patients atteints de maladies auto-immunes recevant de tels traitements, en particulier ceux atteints de vascularites associées aux ANCA (AAV), il est donc nécessaire de développer des stratégies vaccinales anti-pneumococciques améliorées pour augmenter la réponse immunitaire et la protection vaccinale.

Patients et méthodes

Cet essai multicentrique de phase 2, randomisé, ouvert, a comparé deux stratégies innovantes de vaccin anti-pneumococcique « renforcées » au schéma de vaccination standard chez des patients atteints de VAA recevant un traitement par RTX. Des patients adultes atteints de VAA nouvellement diagnostiquée ou en rechute, présentant une maladie active (BVAS ≥ 3) et devant recevoir du RTX comme traitement d’induction (375 mg/m²/semaine pendant 4 semaines consécutives), ont été randomisés avec un rapport 1:1:1 dans trois bras parallèles : schéma standard associant une dose de vaccin pneumococcique conjugué 13-valent (PCV13) au jour 0 suivie d’une dose de vaccin non conjugué 23-valent (PPV23) au mois 5 (M5) (bras 1) ; double dose de PCV13 au jour 0 et au jour 7 suivie d’une dose de PPV23 à M5 (bras 2) ; ou 4 doses de PCV13 au jour 0 suivies d’une dose de PPV23 à M5 (bras 3). Le critère d’évaluation principal était la réponse immunitaire à M6 contre les 12 sérotypes de pneumocoque communs aux vaccins PCV13 et PPV23, classée selon quatre catégories ordonnées de réponse : réponse positive en anticorps contre 0–3, 4–6, 7–9 ou 10–12 sérotypes. Une réponse positive par sérotype était définie par un titre ELISA d’IgG spécifiques ≥ 1 μg/mL et une augmentation de deux fois par rapport au jour 0. Le critère d’évaluation primaire a été analysé dans un modèle de régression logistique à chances proportionnelles avec une correction de Bonferonni pour les 2 bras innovants. Les critères d’évaluation secondaires étaient les réactions locales et systémiques sollicitées 7 jours après chaque vaccination et tout événement indésirable lié ou pouvant être lié à l’immunisation vaccinale.

Résultats

Quatre-vingt-quinze participants ont été analysés dans la population modifiée en intention de traiter (âge moyen 60 ± 16,6 ans, 50 % d’hommes, 74 personnes atteintes d’une maladie nouvellement diagnostiquée, 66 d’une granulomatose avec polyangéite et 29 d’une polyangéite microscopique, BVAS moyen 15,3 ± 6,9), dont 30 affectés au bras 1, 32 au bras 2 et 33 au bras 3.

À M6, une réponse immunitaire contre 0–3, 4–6, 7–9 ou 10–12 sérotypes était observée chez 83,3 %, 13,3 %, 3,3 % et 0 % dans le bras 1 ; 56,3 %, 28,1 %, 15,6 % et 0 % dans le bras 2 ; et 60,6 %, 33,3 %, 6,1 % et 0 % dans le bras 3. Les patients du bras 2 étaient significativement plus susceptibles de se trouver dans une catégorie de réponse supérieures par rapport au régime standard après ajustement sur l’âge, avec un odds ratio proportionnel (pOR) de 4,1 (IC97,5 % : 1,1–15,9, p = 0,018), tandis que le bras 3 montrait une tendance non significative à améliorer les réponses vaccinales (pOR : 3,1, IC97,5 % : 0,8–11,9, p = 0,062). Une analyse de sensibilité sur une population per-protocole excluant les patients ayant subi des vaccinations ou des prises de sang hors des délais donnait des estimations concordantes.

Les réactions locales et/ou systémiques dans les 7 jours après chaque vaccination, et tout événement indésirable lié ou possiblement lié à la vaccination au cours des 6 premiers mois, sont survenus en plus grand nombre avec les schémas renforcés mais étaient principalement des réactions locales de grade 1 ou 2. Aucun événement indésirable grave lié à la vaccination n’a été observé.

Au cours du suivi, 8 poussées de vascularite sont survenues chez 6 patients, en médiane 87 jours après la dernière vaccination : un patient dans le bras 1, 2 dans le bras 2, et 3 dans le bras 3.

Conclusion

Chez les patients atteints de VAA recevant un traitement par RTX, une stratégie innovante de vaccination anti-pneumococcique renforcée, basée sur une double dose de PCV13 au jour 0 et au jour 7 suivie d’une dose unique de PPV23 à M5, améliore significativement les réponses en anticorps contre Streptococcus pneumoniae par rapport au schéma standard.

[Characteristics of patients with connective tissue disease-associated pulmonary arterial hypertension treated with prostanoids: A multicenter retrospective study]

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a severe complication of connective tissue disease (CTD). Data on use of prostanoids in this particular subset of patients are lacking. We aimed to describe the characteristics of patients with PAH-CTD treated with prostanoids and the outcomes under treatment.

METHODS

In this multicenter retrospective study, all patients treated with prostanoids since 2006 were included. Data on PAH and CTD were collected at the time of prostanoid introduction and under treatment.

RESULTS

Twenty-one patients were included, of whom 20 (95%) had limited cutaneous systemic sclerosis. Nineteen patients were treated with oral monotherapy or combination before addition of prostanoid. Treprostinil was the most used molecule (57% of patients). At the time of prostanoid introduction, 90% of patients were considered at high risk for death. Among patients who had right heart catheterization during follow-up, there was no significant difference in haemodynamics. No extrarespiratory worsening of the CTD was reported. The 1-year survival under prostanoid was 62%. In univariate analysis, NYHA functional class was associated with survival under treatment.

CONCLUSION

This study provides original data on use of prostanoids in a cohort consisting mainly of systemic sclerosis. It underlines the difficulty to achieve a standardized assessment in this subset of patients. Safety profile was comparable with data reported in idiopathic PAH.

OP0295 GR2 MULTICENTRIC PROSPECTIVE FRENCH STUDY’S RESULTS: DAMAGE BUT NOT REMISSION AT FIRST TRIMESTER PREDICTS ADVERSE PREGNANCY OUTCOME IN LUPUS PREGNANCIES

Background:

Active Systemic Lupus Erythematosus (SLE) during pregnancy is associated with poor obstetrical outcome but it is still not clear if remission, lupus low disease activity state (LLDAS) is the best target to achieve at conception. Besides, the effect of damage on pregnancy outcome has not been studied.

Objectives:

Our aim was to determine the 1st trimester risk factors for adverse pregnancy outcome (APO).

Methods:

Inclusion criteria were: 1) women≥18 years enrolled in the prospective GR2 study; 2) with SLE (SLICC criteria); 3) and an ongoing singleton pregnancy at 12 weeks (only 1 pregnancy per patient). We used the following definitions: DORIS1, DORIA2, clinical SLEDAI-2K=0, LLDAS3 (for SLE activity), SFI4 (for flares), and SLICC-damage index5 (for damage). APO included: foetal death, neonatal death, placental insufficiency with premature delivery<37 weeks, and small for gestational age (SGA:≤3rd percentile).

Results:

238 patients were included. 234 (98.3%) women were on hydroxychloroquine (HCQ) and 206 (86.5%) had a clinical SLEDAI-2K=0. Regarding pregnancy outcome, 230 (96.6%) patients had a live birth (mean term 37.7 weeks). Thirty-four (14.3%) patients developed at least 1 APO: placental insufficiency (n=22), foetal death (n=7), neonatal death (n=1), and SGA (n=5). Two different regression logistic models were assessed, one for DORIA and one for LLDAS. We found that only SLICC-Damage index and lupus anticoagulant (LAC) were associated with APO (p=0.02, OR 1.8, 95% CI: 1.1-2.9; p=0.001, OR 4.2, 95% CI: 1.8-9.7 respectively for DORIA model; p=0.03, OR 1.7, 95% CI:1.1-2.8; p=0.002, OR 3.7, 95% CI: 1.6-8.7 respectively for LLDAS model).

Conclusion:

We confirmed that LAC predicts APO. We found for the first time that chronic damage at 1st trimester also predicted APO. No effect of remission/LLDAS was observed in this cohort of patients on HCQ with a stable and well-controlled SLE.

References:

[1]van Vollenhoven R, et al. ARD 2017.

[2]Zen M, et al. ARD. 2015.

[3]Franklyn, K. et al. ARD 2016.

[4]Petri M, et al. NEJM 2005.

[5]Gladman DD, et al. Arthritis Rheum, 1997.

Table 1.Univariate analysis for APOMaternal featuresTotal (N=238)APO (N=34)Non-APO (N=204)P valueAge, mean (SD)31.6(4.5)30.7(4.8)31.7(4.4)0.22Secondary APS34(14.3)10(29.4)24(11.8)0.01Previous renal phenotype67(28.2)13(38.2)54(26.5)0.16At least 1 flare during pregnancy37(15.5)6(17.4)31(15.2)0.80Positive anti-DNA (N=222)104(46.8)21(67.7)83(43.5)0.01Hypocomplementemia (N=216)57(26.4)13(40.6)44(23.9)0.05LAC (N=232)41(17.7)15(44.1)26(13.1)<0.001Triple aPL (N=232)17(7.3)5(14.7)12(6.1)0.0824h-proteinuria>0.5g/day9(3.8)3(8.8)6(2.9)0.12Activity/DamageSLEDAI-2K, median (IQR) (N=212)2(0-3)2(2-4)2(0-2)0.01SLICC-DI, median (IQR) (N=236)0(0-0)0(0-0)0(0-0)0.007PGA, median (IQR)(N=235)0.1(0-0.2)0.1(0-0.41)0.1(0-0.2)0.06DORIA remission*154(64.7)17(50.0)137(67.2)0.05DORIS remission**147(61.8)17(50.0)130(63.4)0.13LLDAS (N=219)157(71.7)19(57.6)138(74.2)0.05Clinical SLEDAI-2K=0206(86.5)28(82.4)178(87.3)0.44TreatmentPrednisone (PDN)119(50.0)23(67.7)96(47.1)0.03PDN (mg/day) median (IQR)7(5-10)0(0-6)5(0-10)0.007Immunosuppressants57(24.0)13(38.2)44(21.6)0.04Hydroxychloroquine234(98.3)34(100.0)200(98.0)1.00Low dose aspirin165(69.3)29(85.3)136(66.7)0.03Low molecular weight heparin61(25.6)15(44.1)46(22.6)0.01

Legend: APS: antiphospholipid syndrome; aPL: antiphospholipid; PGA: Physician global assessment. *: DORIA definition of remission = clinical SLEDAI=0 and prednisone ≤5 mg/day; **: DORIS definition of remission = clinical SLEDAI=0, prednisone ≤5 mg/day, and PGA<0.5.

Disclosure of Interests:

None declared.

Different phenotypes in dermatomyositis associated with anti-MDA5 antibody: Study of 121 cases

OBJECTIVES

The predominance of extramuscular manifestations (e.g., skin rash, arthralgia, interstitial lung disease [ILD]) as well as the low frequency of muscle signs in anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5+) dermatomyositis caused us to question the term myositis-specific antibody for the anti-MDA5 antibody, as well as the homogeneity of the disease.

METHODS

To characterize the anti-MDA5+ phenotype, an unsupervised analysis was performed on anti-MDA5+ patients (n = 83/121) and compared to a group of patients with myositis without anti-MDA5 antibody (anti-MDA5-; n = 190/201) based on selected variables, collected retrospectively, without any missing data.

RESULTS

Within anti-MDA5+ patients (n = 83), 3 subgroups were identified. One group (18.1%) corresponded to patients with a rapidly progressive ILD (93.3%; p < 0.0001 across all) and a very high mortality rate. The second subgroup (55.4%) corresponded to patients with pure dermato-rheumatologic symptoms (arthralgia; 82.6%; p < 0.01) and a good prognosis. The third corresponded to patients, mainly male (72.7%; p < 0.0001), with severe skin vasculopathy, frequent signs of myositis (proximal weakness: 68.2%; p < 0.0001), and an intermediate prognosis. Raynaud phenomenon, arthralgia/arthritis, and sex permit the cluster appurtenance (83.3% correct estimation). Nevertheless, an unsupervised analysis confirmed that anti-MDA5 antibody delineates an independent group of patients (e.g., dermatomyositis skin rash, skin ulcers, calcinosis, mechanic's hands, ILD, arthralgia/arthritis, and high mortality rate) distinct from anti-MDA5- patients with myositis.

CONCLUSION

Anti-MDA5+ patients have a systemic syndrome distinct from other patients with myositis. Three subgroups with different prognosis exist.

Giant cell arteritis-related aortitis with positive or negative temporal artery biopsy: a French multicentre study

Objective: To compare the clinical presentation and outcome of giant cell arteritis (GCA)-related aortitis according to the results of temporal artery biopsy (TAB).Method: Patients with GCA-related aortitis diagnosed between 2000 and 2017, who underwent TAB, were retrospectively included from a French multicentre database. They all met at least three American College of Rheumatology criteria for the diagnosis of GCA. Aortitis was defined by aortic wall thickening > 2 mm on computed tomography scan and/or an aortic aneurysm, associated with an inflammatory syndrome. Patients were divided into two groups [positive and negative TAB (TAB+, TAB-)], which were compared regarding aortic imaging characteristics and aortic events, at aortitis diagnosis and during follow-up.Results: We included 56 patients with TAB+ (70%) and 24 with TAB- (30%). At aortitis diagnosis, patients with TAB- were significantly younger than those with TAB+ (67.7 ± 9 vs 72.3 ± 7 years, p = 0.022). Initial clinical signs of GCA, inflammatory parameters, and glucocorticoid therapy were similar in both groups. Coronary artery disease and/or lower limb peripheral arterial disease was more frequent in TAB- patients (25% vs 5.3%, p = 0.018). Aortic wall thickness and type of aortic involvement were not significantly different between groups. Diffuse arterial involvement from the aortic arch was more frequent in TAB- patients (29.1 vs 8.9%, p = 0.03). There were no differences between the groups regarding overall, aneurism-free, relapse-free, and aortic event-free survival.Conclusion: Among patients with GCA-related aortitis, those with TAB- are characterized by younger age and increased frequency of diffuse arterial involvement from the aortic arch compared to those with TAB+, without significant differences in terms of prognosis.

Pulmonary manifestations revealing Rosai-Dorfman disease

Rosai-Dorfman disease is a rare non-Langerhans cell histiocytosis, mainly involving cervical nodes. We present the case of a patient with a pulmonary form of Rosai-Dorfman disease without peripheral or intra-thoracic lymph nodes, characterized by the presence of pulmonary nodules and cysts associated with bilateral pleural effusions.

Mycophenolate mofetil in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis: a prospective pharmacokinetics and clinical study

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) treatment strategy is based on immunosuppressive agents. Little information is available concerning mycophenolic acid (MPA) and the area under the curve (AUC) in patients treated for AAV. We evaluated the variations in pharmacokinetics for MPA in patients with AAV and the relationship between MPA-AUC and markers of the disease. MPA blood concentrations were measured through the enzyme-multiplied immunotechnique (C(0), C(30), C(1), C(2), C(3), C(4), C(6) and C(9)) to determine the AUC. Eighteen patients were included in the study. The median (range) MPA AUC(0-12) was 50·55 (30·9-105·4) mg/h/l. The highest coefficient of determination between MPA AUC and single concentrations was observed with C(3) (P < 0·0001) and C(2) (P < 0·0001) and with C(4) (P < 0·0005) or C(0) (P < 0·001). Using linear regression, the best estimation of MPA AUC was provided by a model including C(30), C(2) and C(4): AUC = 8·5 + 0·77 C(30) + 4·0 C(2) + 1·7 C(4) (P < 0·0001). Moreover, there was a significant relationship between MPA AUC(0-12) and lymphocyte count (P < 0·01), especially CD19 (P < 0·005), CD8 (P < 0·05) and CD56 (P < 0·05). Our results confirm the interindividual variability of MPA AUC in patients treated with MMF in AAV and support a personalized therapy according to blood levels of MPA.

Chronic bronchiolitis in ankylosing spondylitis

The pleuro-pulmonary signs of ankylosing spondylitis are generally asymptomatic, typically represented by biapical lung fibrosis. To our knowledge, the severe bronchiolitis which is sometimes observed in other spondyloarthropathies has not been described in ankylosing spondylitis. We report two cases of severe chronic bronchiolitis in ankylosing spondylitis patients. Their clinical and radiological presentation were similar, characterized by progressive deterioration of stage III-IV dyspnea, non-reversible obstructive ventilatory defect, and CT scan showing air trapping with mosaic attenuation and ground-glass opacity in expiration. Lung biopsies confirmed the diagnosis of severe follicular bronchiolitis in one patient and constrictive bronchiolitis is suspected in the other. Only the patient with follicular bronchiolitis responded positively to treatment with low doses of macrolides.

Clinical manifestations and outcome of anti-PL7 positive patients with antisynthetase syndrome

BACKGROUND

The aims of the present study were to determine both clinical manifestations and outcome of anti-PL7 patients with antisynthetase syndrome (ASS).

METHODS

The medical records of 15 consecutive anti-PL7 patients with biopsy proven ASS were retrospectively analyzed without prior selection.

RESULTS

Anti-PL7 patients exhibited polymyositis (n=14) and dermatomyositis (n=1); extra-pulmonary manifestations of ASS included: Raynaud's phenomenon (40%), mechanic's hands (33.3%), joint impairment (26.7%), pericardial effusion (20%) and esophageal/gastrointestinal involvement (20%). The outcome of myositis was as follows: remission/improvement (91.7%) and deterioration (8.3%). Fourteen patients (93.3%) experienced interstitial lung disease (ILD). ILD preceded ASS diagnosis (n=5), was identified concomitantly with ASS (n=8) and occurred after ASS diagnosis (n=1). Patients could be divided into 3 groups according to their presenting lung manifestations: acute onset of lung disease (n=1), progressive onset of lung signs (n=11) and asymptomatic patients exhibiting abnormalities consistent with ILD on PFT and HRCT-scan (n=2). No patient had resolution of ILD, whereas 64.3% and 35.7% experienced improvement and deterioration of ILD, respectively. ILD resulted in respiratory insufficiency requiring O2 therapy in 14.3% of cases. Two patients died. Predictive parameters of ILD deterioration were: DLCO<45% at ILD diagnosis and HRCT-scan pattern of usual interstitial pneumonia (UIP).

CONCLUSION

Our series mainly underscores that ILD is frequent in anti-PL7 patients, leading to high morbidity. Our study further suggests that patients with predictive factors of ILD deterioration may require more aggressive therapy, especially the group of patients with DLCO<45% at ILD diagnosis and UIP pattern on HRCT-scan.

[Cardio-respiratory involvement in adult-onset Still's disease]

Cardiopulmonary involvement in adult-onset Still's disease is not as common as cutaneous and articular involvement. Pleuropericarditis is the most frequent thoracic manifestation. Although difficult, diagnosis of other thoracic manifestations, which may reveal the disease, is crucial, due to the high risk to life and the efficacy of new immunosuppressive agents. The pathophysiology involves essentially immunological factors, Still's disease being increasingly seen as an autoimmune inflammatory disease. Pro-inflammatory cytokines such as interleukine (IL) 1, 6 and 18 play a crucial role in macrophage activation, which is central in the pathophysiology of adult Still's disease. The classification of cardiopulmonary manifestations is based on anatomy. Cardiac lesions may involve all the tissues of the heart and the pulmonary arteries. Respiratory lesions may involve the pleura, the lung parenchyma (organizing pneumonitis, infiltrative lung disease, alveolar damage, amyloidosis), and the respiratory muscles, including the diaphragm. Finally, some manifestations may be provoked by the treatment itself. Steroids, the first-line treatment, are very effective in pleuropericarditis. Methotrexate used to be prescribed when steroids failed, but biotherapies such as IL1 and IL6 inhibitors have transformed the prognosis of forms resistant to these drugs.

Brief report: candidate gene study in systemic sclerosis identifies a rare and functional variant of the TNFAIP3 locus as a risk factor for polyautoimmunity

OBJECTIVE

Systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) share some pathophysiologic bases as evidenced by individual and familial polyautoimmunity and common susceptibility genetic factors. With regard to the latter, there has been a recent shift from the "common variant" to the "rare variant" paradigm, since rare variants of TNFAIP3 and TREX1 with large effect sizes have recently been discovered in SLE. The present study was undertaken to investigate whether rare variants of TNFAIP3 and TREX1 are also associated with SSc.

METHODS

TREX1 single-nucleotide polymorphisms (SNPs) rs3135946, rs7626978, rs3135943, and rs11797 and TNFAIP3 SNPs rs9494883, rs72063345, rs5029939, rs2230926, rs117480515, and rs7749323 were genotyped in a discovery set (985 SSc patients and 1,011 controls), and replication analysis of the most relevant results was performed in a second set (622 SSc patients and 493 controls).

RESULTS

No association between TREX1 variants and SSc was observed. For TNFAIP3, we first demonstrated that a low-frequency variant, rs117480515, tagged the recently identified TT>A SLE dinucleotide. In the discovery sample, we observed that all tested TNFAIP3 variants were in linkage disequilibrium and were associated with SSc and various SSc subsets, including the polyautoimmune phenotype. We subsequently genotyped rs117480515 in the replication sample and found it to be associated solely with the SSc polyautoimmune subset (odds ratio 3.51 [95% confidence interval 2.28-5.41], P = 8.58 × 10(-9) ) in the combined populations. Genotype-messenger RNA (mRNA) expression correlation analysis revealed that the TNFAIP3 rs117480515 risk allele was associated with decreased mRNA expression.

CONCLUSION

The present findings establish the TNFAIP3 locus as a susceptibility factor for the subset of SSc with a polyautoimmune phenotype. Our results support the implication of rare/low-frequency functional variants and the critical role of A20 in autoimmunity.