Genetic association study of NF-κB genes in UK Caucasian adult and juvenile onset idiopathic inflammatory myopathy.

Objective: Treatment-resistant muscle wasting is an increasingly recognized problem in idiopathic inflammatory myopathy (IIM). TNF-α is thought to induce muscle catabolism via activation of nuclear factor-kappa B (NF-κB). Several genes share homology with the NF-κB family of proteins.

International consensus on a proposed score system for muscle biopsy evaluation in patients with juvenile dermatomyositis: a tool for potential use in clinical trials.

Objective: To devise and test a system with which to evaluate abnormalities on muscle biopsy samples obtained from children diagnosed with juvenile dermatomyositis (DM).

Methods: We established an International Consensus Group on Juvenile DM Biopsy and carried out 2 phases of consensus process and scoring workshops. Biopsy sections (n = 33) were stained by standard methods.

Paediatric idiopathic inflammatory muscle disease.

The paediatric idiopathic inflammatory myopathies (IIMs) are a group of rare but serious systemic autoimmune conditions of childhood. The most common of the paediatric IIMs is juvenile dermatomyositis (JDM), while polymyositis and inclusion body myositis are rare in children. JDM has a significantly different spectrum of disease from adult dermatomyositis.

MHC Class I overexpression on muscles in early juvenile dermatomyositis.

Objective: To assess muscle expression of MHC Class I complexes (heavy chain and beta2-microglobulin) and to analyze the composition of infiltrating mononuclear cells, specifically cells that bear receptors for class I MHC molecules, in the muscles of children with early juvenile dermatomyositis (JDM).

Methods: Light microscopic and immunohistochemical analysis of muscle biopsies from 10 patients with JDM and 3 controls. The mean duration from initial weakness was 2.