C-terminal variants in CDC42 drive type I interferon-dependent autoinflammation in NOCARH syndrome reversible by ruxolitinib.

C-terminal variants in CDC42 encoding cell division control protein 42 homolog underlie neonatal-onset cytopenia, autoinflammation, rash, and hemophagocytic lymphohistiocytosis (NOCARH). Pyrin inflammasome hyperactivation has been shown to contribute to disease pathophysiology. However, mortality of NOCARH patients remains high despite inflammasome-focused treatments.

Multisystem inflammatory syndrome in children during the COVID-19 waves: data from the Juvenile Inflammatory Rheumatism cohort.

Introduction: Multisystem inflammatory syndrome in children (MIS-C) is a new condition that first appeared in children and adolescents during the COVID-19 pandemic. We aimed to describe the diagnostic course, clinical and biological manifestations, and treatment of MIS-C during the first three COVID-19 waves.

Methods: We extracted patient data from the Juvenile Inflammatory Rheumatism (JIR) cohort.

Individual and environmental determinants associated with longer times to access pediatric rheumatology centers for patients with juvenile idiopathic arthritis, a JIR cohort study.

Background: Despite guidelines, poor access to appropriate care for juvenile idiopathic arthritis (JIA) patients remains a global issue. Prompt referral to a pediatric rheumatology (PR) center and effective care is known to be critical for changing the natural history of the disease and improving long-term prognosis. This project assesses socio-economic factors of delayed referral to a pediatric rheumatologist (PRst) for JIA patients in France and Switzerland within the Juvenile Inflammatory Rheumatism (JIR) Cohort.

Factors associated with poor prognosis of hip arthritis in juvenile idiopathic arthritis: Data from the JIR cohort.

Objectives: Hip involvement remains a predictor of severe juvenile idiopathic arthritis (JIA) course and carries a high risk of disability. This study aims to determine the factors of poor prognosis of hip involvement in patients with JIA and to assess the treatment response.

Methods: This is a multicenter observational cohort study.

Joint involvement in Noonan syndrome. A retrospective paediatric descriptive study.

Objectives: Noonan syndrome is a rare genetic disorder characterized mainly by congenital heart disease, occasional intellectual disability, and varied orthopaedic, rheumatological and haematologic anomalies. Despite potentially serious functional consequences, joint involvement has been rarely studied in the literature. Our objective was to perform a retrospective study evaluating the prevalence and characteristics of joint involvement in Noonan syndrome.

Etanercept concentration and immunogenicity do not influence the response to Etanercept in patients with juvenile idiopathic arthritis.

Objective: To investigate the relationship of clinical response of Juvenile Idiopathic Arthritis (JIA) to etanercept (ETN) with ETN levels, and the presence of anti-drug antibodies to ETN (ADAb).

Methods: Prospective study of JIA patients under 18 years old. Clinical and pharmacological data were collected at two visits.

Single amino acid charge switch defines clinically distinct proline-serine-threonine phosphatase-interacting protein 1 (PSTPIP1)-associated inflammatory diseases.

Background: Hyperzincemia and hypercalprotectinemia (Hz/Hc) is a distinct autoinflammatory entity involving extremely high serum concentrations of the proinflammatory alarmin myeloid-related protein (MRP) 8/14 (S100A8/S100A9 and calprotectin).

Objective: We sought to characterize the genetic cause and clinical spectrum of Hz/Hc.

Methods: Proline-serine-threonine phosphatase-interacting protein 1 (PSTPIP1) gene sequencing was performed in 14 patients with Hz/Hc, and their clinical phenotype was compared with that of 11 patients with pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome.

A new mutation in the C-SH2 domain of PTPN11 causes Noonan syndrome with multiple giant cell lesions.

Noonan syndrome (NS), an autosomal dominant multisystem disorder, is caused by the dysregulation of the RAS-MAPK pathway and is characterized by short stature, heart defects, pectus excavatum, webbed neck, learning problems, cryptorchidism and facial dysmorphism. We here present the clinical and molecular characterization of a family with NS and multiple giant cell lesions (MGCLs). The proband is a 12-year-old girl with NS and MGCL.

Evaluation of health related quality of life in children with immune thrombocytopenia with the PedsQL™ 4.0 Generic Core Scales: a study on behalf of the pays de Loire pediatric hematology network.

Background: Immune thrombocytopenia (ITP) is a childhood disorder that is often life-altering for children and their parents. Health related quality of life (HRQL) has never been chronologically monitored in children with ITP. We initiated a prospective study to assess HRQL from diagnosis to six months and define factors that influence this outcome in children with ITP.

Progressive polyepiphyseal dysplasia with arthropathy: a distinct disorder from idiopathic juvenile arthritis and pseudorheumatoid dysplasia?

Juvenile idiopathic arthritis is an inflammatory disease with various onset-forms which can sometimes be difficult to distinguish from genetic inflammatory/rheumatoid-like osteoarthropathies. In this report, we describe two boys with severe chronic arthralgia, stiffness and swelling of joints, motor weakness and joints contractures evolving despite immunosuppressive treatments and for whom all biological and molecular exams failed to identify a prompt diagnosis. Some findings also overlap with pseudorheumatoid dysplasia but WISP3 gene molecular analysis failed to identify any mutation for both patients.