Intravenous immunoglobulin is an effective steroid-sparing drug in inflammatory myositis.

INTRODUCTION

Glucocorticoids are the cornerstone of treatment of idiopathic inflammatory myositis (IIM) but are associated with significant side effects, especially during long-term use. Intravenous immunoglobulin (IVIG) has emerged as a promising steroid-sparing alternative, particularly for refractory cases.

METHODS

This retrospective cohort study included patients aged ≥ 18 years treated with IIM who received IVIG treatment between August 2018 and August 2023. Outcomes included changes in myositis-related symptoms, functional exercise tests, creatinine kinase (CK) levels and prednisolone dosage at three and six months.

RESULTS

A total of 22 patients were included, with the most common IIM subtypes being polymyositis (36%), immune-mediated necrotizing myopathy (23%) and dermatomyositis (18%). Dysphagia improved in 87.5% of patients, and cardiac symptoms resolved in all affected individuals by six months. Significant improvements were observed in functional performance and CK levels at both time points. Prednisolone dosage decreased from 44.7 mg/day (standard deviation (SD): ± 29.7) at baseline to 9.9 mg/day (SD: ± 12.8) at six months, representing a 77% reduction.

CONCLUSIONS

IVIG is an effective treatment and steroid-sparing therapy in IIM, yielding substantial reductions in glucocorticoid use, symptom improvement and functional recovery. These findings suggest that IVIG may be considered earlier in the disease course, especially in patients with contraindications to glucocorticoids.

FUNDING: None.

TRIAL REGISTRATION: This study was not registered as it was a quality improvement project and did not meet criteria for trial registration.