Particularités cliniques et physiopathologiques de l’atteinte articulaire au cours de la vascularite à IgA chez l’adulte : étude de deux cohortes françaises

Introduction: Articular involvement in adult form-IgA vasculitis (IgAV) is a frequent manifestation. The aim of this study was to characterize articular involvement, to identify the clinical and biological phenotype of patients with joints involvement and to understand the physiopathological mechanism of this presentation. Methods: We used data of IGAVAS survey, a French retrospective multicentric cohort, to characterize articular involvement and to compare characteristics of patients with and without joints involvement. We compared cytokine and T-cells concentrations in the plasma using data and samples from HSPrognosis cohort, a French prospective study. Results: Among 260 patients, 160 had articular involvement, mainly arthralgias of knees and ankles, resolving in 96% cases. Those patients were younger (OR=0.87; p=0.0021) and had more gastro-intestinal tract involvements (OR=2.080; p=0.0116). No difference was demonstrated on relapses or survival. Serum interleukin-1β (IL-1β) level was higher in patients with joints involvement. Conclusion: Articular involvement is a frequent manifestation of IgAV in adults, mainly arthralgias of knees and ankles, with favorable evolution. It was associated with a younger age and more frequent gastro-intestinal tract involvements, which conditions short term prognosis. Those patients had a higher serum IL-1β level, suggesting implication of IL-1β in articular involvement physiopathology and the potential interest of Il-1 blocking agents in the treatment.Introduction : l’atteinte articulaire au cours de la vascularite à IgA (VIgA) chez l’adulte est fréquente. Cette étude visait à décrire ces manifestations articulaires, à identifier le phénotype clinicobiologique des patients présentant ces atteintes, et à en étudier la physiopathologie. Méthodes : nous avons utilisé les données de l’étude IGAVAS, une cohorte rétrospective multicentrique française, afin de caractériser les atteintes articulaires, et de comparer les phénotypes des patients en fonction de la présence ou non d’une atteinte articulaire. Nous avons comparé les taux sanguins de cytokines et de lymphocytes T en utilisant les données de la cohorte prospective multicentrique française HSPrognosis. Résultats : sur 260 patients, 160 avaient une atteinte articulaire, principalement des arthralgies des genoux et des chevilles, résolutives dans 96% des cas. Ces patients étaient plus jeunes (OR=0,87 ; p=0,0021) et présentaient plus d’atteinte digestive (OR=2,08 ; p=0,0116). Il n’y avait pas de différence en termes de rechutes ou de survie. Les patients présentant une atteinte articulaire avaient un taux sérique d’interleukine-1β (IL-1β) plus élevé. Conclusion : l’atteinte articulaire est fréquente au cours de la VIgA de l’adulte. Il s’agit principalement d’arthralgies des genoux et des chevilles, d’évolution favorable. Ces patients sont plus jeunes et ont plus d’atteintes digestives, or l’atteinte digestive conditionne le pronostic à court terme. Ils ont un taux sérique d’IL-1β plus élevé. Cela suggère l’implication de cette cytokine dans la physiopathologie de l’atteinte articulaire au cours de la VIgA chez l’adulte, et en fait une cible thérapeutique potentielle

Clinical phenotype and cytokine profile of adult IgA vasculitis with joint involvement

International audienceObjective Joint involvement can be observed during the course of adult IgA vasculitis (IgAV). However, clinical picture, prognosis, or pathophysiological data associated with this condition have been overlooked. We aimed to describe the clinical characteristics and outcome of IgAV patients with joint involvement and look to a specific cytokine profile.Methods We analyzed clinical and biological data from a nationwide study that included adult IgAV patients. Presentation and outcomes of patients with or without joint involvement were compared at baseline and during follow-up. Plasma cytokine measurements of IgAV patients included in a prospective study were also analyzed using multiplex assays.Results Among 260 patients, 62% had joint involvement. Among them, rheumatological manifestations included arthralgia (100%) or arthritis (16%), mostly involving the knees and ankles. In multivariate analysis, patients with joint involvement, compared to those without, were younger (p = 0.002; OR 0.87; 95% CI 0.80-0.95) and showed more frequent gastrointestinal tract involvement (p = 0.012; OR= 2.08; 95% CI 1.18-3.67). However, no difference in terms of clinical response, relapse, end-stage renal disease, or death was observed between groups. Among 13 cytokines measured, plasma interleukin (IL)-1 beta level was higher in patients with joint involvement compared to those without (mean +/- SEM IL-1 beta, 3.5 +/- 1.2 vs. 0.47 +/- 0.1 pg/ ml; p = 0.024) or healthy controls (vs. 1.2 +/- 0.5 pg/ml; p = 0.076).Conclusion Joint involvement is frequent in adult IgAV and is associated with more frequent gastrointestinal involvement. Increased plasma IL-1 beta levels raise the question of targeting this cytokine in patients with chronic and/or refractory joint involvement