A novel serum calprotectin (MRP8/14) particle-enhanced immuno-turbidimetric assay (sCAL turbo) helps to differentiate systemic juvenile idiopathic arthritis from other diseases in routine clinical laboratory settings.

Background: Differential diagnosis in children with signs of unprovoked inflammation can be challenging. In particular, differentiating systemic juvenile idiopathic arthritis (SJIA) from other diagnoses is difficult. We have recently validated the complex of myeloid-related proteins 8/14 (MRP8/14, also known as S100A8/A9 complex or serum calprotectin) as a helpful biomarker supporting the diagnosis of SJIA.

Type 1 Interferon-Stimulated Gene Expression and Disease Activity in Pediatric Rheumatic Diseases: No Composite Scores Needed?

Objective: Rheumatic diseases are characterized by different patterns of immune overactivation. This study investigated the correlation of whole blood type 1 interferon (IFN) stimulated gene (ISG), IL18, and CXCL9 expression with clinical disease activity in pediatric rheumatic diseases and assessed the required number of ISGs to be included in a composite type 1 IFN score.

Methods: Whole blood-derived RNA and clinical data were collected from 171 mostly pediatric patients with connective tissue diseases (CTDs), systemic autoinflammatory diseases (SAIDs), monogenic interferonopathies (IFNPs) and other inflammatory diseases, and from 38 controls.