SLE myopathy: a clinicopathological study.

Aim: To study the histological changes in muscle biopsy in patients diagnosed with systemic lupus erythematosus (SLE) and presenting with muscle symptoms. Materials and Methods: Patients with SLE presenting with muscle symptoms at presentation or during follow-up and treatment between January 2010 and May 2014 and who underwent muscle biopsy were included in the study. Demographic, clinical features, serological markers, and Electromyoneurography findings were collected. Muscle biopsies were evaluated for inflammation, fiber type abnormalities, vasculitis and interstitial changes according to 2004 European Neuromuscular Centre criteria. Results: Fifteen patients underwent muscle biopsy in the study period. Clinical presentations included mucocutaneous (9), musculoskeletal (14), hematological (3), renal (8), hepatic (1) and central nervous system (CNS) (4) manifestations, and neuropathy (4), serositis (2), Raynaud's phenomenon (1) and infectious complications (8). Histological findings were perivascular/perimysial inflammation (7/15), type 1 predominance (7/15) and type 2 atrophy (13/15). Clinical evidence of myositis was seen in 8.8% of patients in the SLE registry, whereas histological evidence of myositis was seen in 46.66% of biopsied patients with muscle symptoms. There was no significant difference in clinical, serological, laboratory and muscle histology features between groups of patients with or without myositis. Type 2 atrophy was the predominant finding in SLE patients irrespective of time of muscle biopsy, treatment received and presence or absence of myositis. Conclusions: Histological evidence of myositis was found in 46.66% of SLE patients and there were no significant differences in clinical/laboratory features in patients with or without myositis. Type 2 atrophy was seen in patients irrespective of time of the biopsy, treatment received and presence or absence of myositis. Type 2 atrophy was considered the major cause for muscle symptoms. [ABSTRACT FROM AUTHOR]