A candidate gene study identifies a haplotype of CD2 as novel susceptibility factor for systemic sclerosis

Objective. Systemic sclerosis (SSc) is a rare autoimmune disease (AID) with a complex genetic aetiology. Evidence for a shared pathogenesis across AIDs is given by the well-known pleiotropism of autoimmune genes. Recently, several unbiased approaches have identified an association between polymorphisms of the CD2 gene, and rheumatoid arthritis (RA) susceptibility. The objective of this study was to investigate whether CD2 polymorphisms are associated with SSc. Methods. Two SNPs of CD2, rs624988 and rs798036, were genotyped in a total of 1,786 SSc patients and 2,360 healthy individuals from two European populations (France and Italy). Meta analyses were performed to assess whether an association exists between CD2 polymorphisms or haplotypes and SSc or its main subtypes. Results. The combined analyses revealed an association between the rs624988 A allele and SSc susceptibility: p(adj)=0.023, OR=1.14 (95%CI 1.04-1.25). Single marker analysis did not reveal any association between rs798036 and SSc. Haplotype analysis identified that the A-T haplotype, previously described in RA, was associated with higher susceptibility for SSc (p(adj)=0.029, OR=1.14, 95%CI 1.04-1.25) and with the positive anticentromere antibody sub-group of SSc patients (p(adj)=0.009, OR=1 95%CI 1.07-1.32). Genotype-mRNA expression correlations revealed that the CD2 risk haplotype was associated with decreased CD2 mRNA expression in SSc patients. Conclusion. Our study establishes CD2 as a new susceptibility factor for SSc, in a European Caucasian population, confirming the sharing of autoimmune risk factors by SSc and RA

Characterisation of a high-risk profile for maternal thrombotic and severe haemorrhagic complications in pregnant women with antiphospholipid syndrome in France (GR2): a multicentre, prospective, observational study

International audienceBackgroundProspective data about the risks of thrombotic and severe haemorrhagic complications during pregnancy and post partum are unavailable for women with antiphospholipid syndrome. We aimed to assess thrombotic and haemorrhagic events in a prospective cohort of pregnant women with antiphospholipid syndrome.MethodsThis multicentre, prospective, observational study was done at 76 centres in France. To be eligible for this study, women had to have diagnosis of antiphospholipid syndrome; have conceived before April 17, 2020; have an ongoing pregnancy that had reached 12 weeks of gestation; and be included in the study before 18 weeks of gestation. Exclusion criteria were active systemic lupus erythematosus nephropathy, or a multifetal pregnancy. Severe haemorrhage was defined as the need for red blood cell transfusion or maternal intensive care unit admission because of bleeding or invasive procedures, defined as interventional radiology or surgery, to control bleeding. The GR2 study is registered with ClinicalTrials.gov, NCT02450396.FindingsBetween May 26, 2014, and April 17, 2020, 168 pregnancies in 27 centres met the inclusion criteria for the study. 89 (53%) of 168 women had a history of thrombosis. The median term at inclusion was 8 weeks gestation. 16 (10%) of 168 women (95%CI 5–15) had a thrombotic (six [4%] women; 95% CI 1–8) or severe haemorrhagic event (12 [7%] women; 95% CI 4–12). There were no deaths during the study. The main risk factors for thrombotic events were lupus anticoagulant positivity at inclusion (six [100%] of six women with thrombosis vs 78 [51%] of 152 of those with no thrombosis; p=0·030) and placental insufficiency (four [67%] of six women vs 28 [17%] of 162 women; p=0·013). The main risk factors for severe haemorrhagic events were pre-existing maternal hypertension (four [33%] of 12 women vs 11 [7%] of 156 women; p=0·014), lupus anticoagulant positivity at inclusion (12 [100%] of 12 women vs 72 [49%] of 146 women; p<0·0001) and during antiphospholipid history (12 [100%] of 12 women vs 104 [67%] of 156 women; p=0·019), triple antiphospholipid antibody positivity (eight [67%] of 12 women vs 36 [24%] of 147 women; p=0·0040), placental insufficiency (five [42%] of 12 women vs 27 [17%] of 156 women; p=0·038), and preterm delivery at 34 weeks or earlier (five [45%] of 11 women vs 12 [8%] of 145 women; p=0·0030).InterpretationDespite treatment adhering to international recommendations, a proportion of women with antiphospholipid syndrome developed a thrombotic or severe haemorrhagic complication related to pregnancy, most frequently in the post-partum period. Lupus anticoagulant and placental insufficiency were risk factors for these life-threatening complications. These complications are difficult to prevent, but knowledge of the antenatal characteristics associated with them should increase awareness and help physicians manage these high-risk pregnancies