MYOSITIS AND MYOPATHIES: Edited by Robert G. Cooper and Hector ChinoyNovel serology testing for sporadic inclusion body myositis disease-specificity and diagnostic utilityHerbert, Megan K.; Pruijn, Ger J.M.Author Information Department of Biomolecular Chemistry, Radboud Institute for Molecular Life Sciences and Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands Correspondence to Ger J.M. Pruijn, Department of Biomolecular Chemistry 284, Radboud University, Nijmegen, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands. Tel: +31 24 361 6847; e-mail: [email protected] Current Opinion in Rheumatology: November 2015 - Volume 27 - Issue 6 - p 595-600 doi: 10.1097/BOR.0000000000000216 Buy Metrics Abstract Purpose of review The purpose of this article is to discuss recent advances in serological testing for sporadic inclusion body myositis (sIBM) and to provide a review of their diagnostic utility and disease-specificity of auto-antibodies in sIBM. Recent findings The identification, prevalence and diagnostic utility of a new auto-antibody targeting cytosolic 5’-nucleotidase 1A (cN-1A) in the serum of sIBM patients have recently been published. These studies have shown that anti-cN-1A auto-antibodies have diagnostic utility for differentiating sIBM from other forms of myositis and from other neuromuscular diseases. Anti-cN-1A-positive patient sera are directed to multiple epitopes of cN-1A and contain, in addition to IgG, IgA and IgM, anti-cN-1A auto-antibodies. Recent studies have also shown a relatively high prevalence of these auto-antibodies in sera form Sjögren's syndrome and systemic lupus erythematosus patients. Summary The recent discovery of auto-antibodies to cN-1A provides a serological tool to aid the differentiation between inflammatory myopathies and supports the idea that apart from degeneration, an adaptive immune response may also play a role in sIBM pathophysiology. Future research will need to focus on standardization of methods to detect these auto-antibodies in order to further explore their specificity and diagnostic utility for sIBM. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.