When do we not use intravenous immunoglobulin treatment in myositis patients?

• A. Severe rapidly progressive cases
• B. Coexistence of arthritis
• C. Steroid resistance
• D. Other immunosuppressive treatments not efficient

Answer: (B)

IVIG is used in inflammatory myopathies primarily to help muscle-dominant disease, especially when weakness is severe, rapidly progressive, or not adequately controlled by steroids and conventional immunosuppressants. It tends to be most helpful for improving muscle strength and, in some cases, dysphagia.

When arthritis is the prominent feature and coexists with myositis, IVIG is not typically the preferred or first-line treatment. Joint disease in these overlap or inflammatory arthritis scenarios responds better to standard DMARDs or biologic agents, and IVIG has limited proven benefit for arthritis. Additionally, IVIG is costly and carries potential risks, so it’s reserved for cases where the myopathy component is the main therapeutic target or when other therapies have failed.

So, the situation where IVIG is not routinely used is when arthritis is the dominant or coexisting issue, shifting the treatment focus toward DMARDs/biologics for the arthritis rather than IVIG for the myositis.