TY - JOUR T1 - Arthritis in Idiopathic Inflammatory Myopathy: Clinical Features and Autoantibody Associations JF - The Journal of Rheumatology JO - J Rheumatol DO - 10.3899/jrheum.131223 SP - jrheum.131223 AU - Martin Klein AU - Heřman Mann AU - Lenka Pleštilová AU - Zoe Betteridge AU - Neil McHugh AU - Martina Remáková AU - Peter Novota AU - Jiří Vencovský Y1 - 2014/05/01 UR - http://www.jrheum.org/content/early/2014/04/28/jrheum.131223.abstract N2 - Objective To determine the prevalence, distribution, and clinical manifestations of arthritis in a cohort of patients with idiopathic inflammatory myopathies (IIM). Associations with autoantibody status and HLA genetic background were also explored. Methods Consecutive patients with IIM treated in a single center were included in this cross-sectional study (n = 106). History of arthritis, 68-joint and 66-joint tender and swollen joint index, clinical features of IIM, and autoantibody profiles were obtained by clinical examination, personal interview, and review of patient records. High-resolution genotyping in HLA-DRB1 and HLA-DQB1 loci was performed in 71 and 73 patients, respectively. Results A combination of patients' medical history and cross-sectional physical examination revealed that arthritis at any time during the disease course had occurred in 56 patients (53%). It was present at the beginning of the disease in 39 patients (37%) including 23 cases (22%) with arthritis preceding the onset of muscle weakness. On physical examination, 29% of patients had at least 1 swollen joint. The most frequently affected areas were wrists, and metacarpophalangeal and proximal interphalangeal joints. Twenty-seven out of the 29 anti-Jo1-positive patients had arthritis at any time during the course of their illness; this prevalence was significantly higher compared to patients without the anti-Jo1 autoantibody (p < 0.0001). No association of arthritis with individual HLA alleles was found. Conclusion Our data suggest that arthritis is a common feature of myositis. It is frequently present at the onset of disease and it may even precede muscular manifestations of IIM. The most common presentation is a symmetrical, nonerosive polyarthritis affecting particularly the wrists, shoulders, and small joints of the hands. We have confirmed a strong association of arthritis with the presence of the anti-Jo1 antibody. ER -