Recurrent polymyositis triggered by bronchiectasis-associated infections

Paediatric and adult bronchiectasis: Specific management with coexisting asthma, COPD, rheumatological disease and inflammatory bowel disease

Bronchiectasis, conventionally defined as irreversible dilatation of the bronchial tree, is generally suspected on a clinical basis and confirmed by means of chest high-resolution computed tomography. Clinical manifestations, including chronic productive cough and endobronchial suppuration with persistent chest infection and inflammation, may deeply affect quality of life, both in children/adolescents and adults. Despite many cases being idiopathic or post-infectious, a number of specific aetiologies have been traditionally associated with bronchiectasis, such as cystic fibrosis (CF), primary ciliary dyskinesia or immunodeficiencies. Nevertheless, bronchiectasis may also develop in patients with bronchial asthma; chronic obstructive pulmonary disease; and, less commonly, rheumatological disorders and inflammatory bowel diseases. Available literature on the development of bronchiectasis in these conditions and on its management is limited, particularly in children. However, bronchiectasis may complicate the clinical course of the underlying condition at any age, and appropriate management requires an integration of multiple skills in a team of complementary experts to provide the most appropriate care to affected children and adolescents. The present review aims at summarizing the current knowledge and available evidence on the management of bronchiectasis in the other conditions mentioned and focuses on the new therapeutic strategies that are emerging as promising tools for improving patients' quality of life.

Idiopathic inflammatory myopathies: from immunopathogenesis to new therapeutic targets

Pathogenesis of idiopathic inflammatory myositis (IIM) involves strong interactions between dendritic cells (DCs), activated Th1 and Th17 cells, B cells, muscle cells, genes and environment. Local maturation of DCs permit the activation and polarization of CD4+ T cells into T(H)1 and T(H)17 that play a key role in maintaining chronic muscle inflammation. T-cell mediated myocytotoxicity promotes the liberation of specific muscle autoantigens from regenerating muscle cells with production of myositis-specific autoantibodies. Type I interferon signature is a key characteristic of IIM. Type I IFN that can be induced by immune complexes containing myositis-specific autoantibodies is produced by scattered plasmacytoid DCs but also by muscle cells particularly regenerating muscle cells. These immature muscle precursors appear to be critical in the pathogenesis of IIM as they up-regulate muscle autoantigens, type I IFN, HLA class I antigens and TLR3-7, all together involved in maintaining chronic muscle inflammation. In addition to the role of immune and muscle cells, genome-wide association studies have confirmed the importance of several MHC and non-MHC genes in IIM. Environmental factors can contribute to the pathogenesis of IIM. In sIBM, distinct features suggest both degenerative and inflammatory processes. In addition to our better understanding of the pathogenesis, identify molecular pathway leads to consider new targeted therapies including cytokine inhibition, B-cell and T-cell costimulation blockade, type I IFN neutralization or inhibition of the ubiquitin proteasome pathway.