Granulomatosis-associated myositis: High prevalence of sporadic inclusion body myositis. (3rd March 2020)

• Record Type: Journal Article
• Authors: Dieudonné, Yannick; Allenbach, Yves; Benveniste, Olivier; Leonard-Louis, Sarah; Hervier, Baptiste; Mariampillai, Kuberaka; Nespola, Benoit; Lannes, Béatrice; Echaniz-Laguna, Andoni; Wendling, Daniel; Von Frenckell, Christian; Poursac, Nicolas; Mortier, Emmanuel; Lavigne, Christian; Hinschberger, Olivier; Magnant, Julie; Gottenberg, Jacques-Eric; Geny, Bernard; Sibilia, Jean; Meyer, Alain
• Is Part Of: Neurology. Volume 94:Number 9(2020)
• Publication Date: 2020-03-03
• Subjects: Neurology -- Periodicals; Neurology -- Periodicals; Neurologie -- Périodiques; 616.8
• DOI: 10.1212/WNL.0000000000008863
• Languages: English
• ISSNs: 0028-3878

Abstract

Abstract : Objective: To refine the predictive significance of muscle granuloma in patients with myositis. Methods: A group of 23 patients with myositis and granuloma on muscle biopsy (granuloma-myositis) from 8 French and Belgian centers was analyzed and compared with (1) a group of 23 patients with myositis without identified granuloma (control-myositis) randomly sampled in each center and (2) a group of 20 patients with sporadic inclusion body myositis (sIBM) without identified granuloma (control-sIBM). Results: All but 2 patients with granuloma-myositis had extramuscular involvement, including signs common in sarcoidosis that were systematically absent in the control-myositis and the control-sIBM groups. Almost half of patients with granuloma-myositis matched the diagnostic criteria for sIBM. In these patients, other than the granuloma, the characteristics of the myopathy and its nonresponse to treatment were similar to the control-sIBM patients. Aside from 1 patient with myositis overlapping with systemic sclerosis, the remaining patients with granuloma-myositis did not match the criteria for a well-defined myositis subtype, suggesting pure sarcoidosis. Matching criteria for sIBM was the sole feature independently associated with nonresponse to myopathy treatment in patients with granuloma-myositis. Conclusion: Patients with granuloma-myositis should be carefully screened for sIBM associated with sarcoidosis in order to best tailor their care.