[A20 haploinsufficiency: what do clinicians need to know?].

A20 Haploinsufficiency (HA20) is a monogenic autoinflammatory disease associated with an autosomal dominant mutation in the TNFAIP3 gene. It induces a defect in the inactivation of the pro-inflammatory NF-κB pathway. Less than 200 cases have been described worldwide.

French national diagnostic and care protocol for Kawasaki disease.

Kawasaki disease (KD) is an acute vasculitis with a particular tropism for the coronary arteries. KD mainly affects male children between 6 months and 5 years of age. The diagnosis is clinical, based on the international American Heart Association criteria.

Multisystem inflammatory syndrome in children and Kawasaki disease: a critical comparison.

Children and adolescents infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are predominantly asymptomatic or have mild symptoms compared with the more severe coronavirus disease 2019 (COVID-19) described in adults. However, SARS-CoV-2 is also associated with a widely reported but poorly understood paediatric systemic vasculitis. This multisystem inflammatory syndrome in children (MIS-C) has features that overlap with myocarditis, toxic-shock syndrome and Kawasaki disease.

Intravenous immunoglobulin immunotherapy for coronavirus disease-19 (COVID-19).

Intravenous immunoglobulin (IVIG), a pooled normal IgG from several thousand healthy donors and one of the commonly used immunotherapeutic molecules for the management of autoimmune and inflammatory diseases, has been explored for the treatment of coronavirus disease-19 (COVID-19). Although placebo-controlled, double-blind randomised clinical trials are lacking, current data from either retrospective, case series or open-label randomised controlled trials provide an indicator that IVIG immunotherapy could benefit severe and critically ill COVID-19 patients. See alsoShao et al.

Efficacy and Safety of Canakinumab in Patients With Systemic Juvenile Idiopathic Arthritis With and Without Fever at Baseline: Results From an Open-Label, Active-Treatment Extension Study.

Objective: To evaluate the long-term efficacy and safety of canakinumab and explore prediction of response in patients with systemic juvenile idiopathic arthritis (JIA) with or without fever at treatment initiation.

Methods: At enrollment, patients with active systemic JIA (ages 2 to <20 years) started open-label canakinumab (4 mg/kg every 4 weeks subcutaneously). Efficacy measures included the adapted American College of Rheumatology (ACR) Pediatric 50/70/90 criteria, the Juvenile Arthritis Disease Activity Score (JADAS), and clinically inactive disease and clinical remission on medication, evaluated by either the JADAS or ACR criteria.

Autoimmune and inflammatory diseases following COVID-19.

Emerging reports show that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection precedes the appearance of various autoimmune and autoinflammatory diseases, including paediatric inflammatory multisystemic syndrome (PIMS) or multisystem inflammatory syndrome in children (MIS-C), thus adding to the growing mystery of this virus and raising questions about the nature of its link with autoimmune and autoinflammatory sequelae.

Acid Stripping of Surface IgE Antibodies Bound to FcεRI is Unsuitable for the Functional Assays that Require Long-Term Culture of Basophils and Entire Removal of Surface IgE.

Basophils are rare granulocytes and dysregulated functions of these cells are associated with several atopic and non-atopic allergic diseases of skin, respiratory system and gastrointestinal tract. Both cytokines and immunoglobulin E (IgE) are implicated in mediating the basophil activation and pathogenesis of these disorders. Several reports have shown that healthy individuals, and patients with allergic disorders display IgG autoantibodies to IgE and hence functional characterization of these anti-IgE IgG autoantibodies is critical.

Intravenous immunoglobulin induces IL-4 in human basophils by signaling through surface-bound IgE.

Background: Therapeutic normal IgG or intravenous immunoglobulin (IVIG) exerts anti-inflammatory effects through several mutually nonexclusive mechanisms. Recent data in mouse models of autoimmune disease suggest that IVIG induces IL-4 in basophils by enhancing IL-33 in SIGN-related 1-positive innate cells. However, translational insight on these data is lacking.