The clinical features and therapeutic results in patients diagnosed with idiopathic inflammatory myositis: single center experience

Abstract

Objective: This study assessed clinical features, laboratory profiles, and treatment outcomes in idiopathic inflammatory myopathies (IIMs) patients after six months of immunosuppression. Method: Retrospective analysis occurred at a tertiary rheumatology center. Baseline and six-month post-therapy assessments were conducted on patients diagnosed with polymyositis or dermatomyositis. Records were kept of clinical symptoms, laboratory markers, and muscle strength scores. Results: With a mean age of 43±11.1 years and an almost even gender distribution (48.4% female), 31 patients were enrolled. Of these individuals, 87.1% were diagnosed with polymyositis and 12.9% with dermatomyositis. At baseline, the predominant symptom was muscle weakness (77.4%), alongside notably high levels of muscle enzymes (median creatinine kinase [CK]: 3340 IU/L) and inflammatory markers (C-reactive protein [CRP]: 11.4 mg/L, erythrocyte sedimentation rate [ESR]: 39 mm/h). Positivity for Jo-1 and Ro52 autoantibodies was found in 16.1% of the cases. Following six months of treatment, there were significant reductions in all laboratory markers (p<0.001), and all patients exhibited improved muscle strength (5/5). Conclusion: Patients with IIMs experience significant biochemical and clinical improvement with immunosuppressive therapy. Optimal recovery and long-term muscle function depend on early diagnosis and personalized treatments.

Keywords

• Dermatomyositis
• idiopathic inflammatory myopathies
• immunosuppressive therapy

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