High dose intravenous immunoglobulin (IVIG) in dermatomyositis: clinical responses and effect on sIL-2R levels.

An open study was conducted to identify and investigate dermatomyositis patients who benefit from IVIG treatment, based on dermatological criteria, myositis-related symptoms and immune/inflammatory parameters. 19 patients (16 females and three males, ages 31-84) suffered from dermatomyositis, and 4/19 patients had paraneoplastic dermatomyositis. We monitored the disease activity by documenting the clinical symptoms, recording muscle-related parameters (electromyography, serum creatine kinase, histopathology), and by determining circulating autoantibodies and serum levels of IL-6, sIL-2R, sTNF-a-R, sICAM-1, and sCD8. 7/19 patients responded to IVIG. They had severe skin but only moderate muscle involvement, no autoantibodies, and no malignancy. IVIG-nonresponders had severe skin and muscle disease, concomitant with autoantibodies and/or malignancy. sIL-2R levels were initially elevated in all patients but reverted to normal in IVIG-responders only. Creatine kinase-levels and other parameters did not correlate with disease activity and/or treatment response. IVIG is effective in selected dermatomyositis patients. sIL-2R serum levels appear to be useful predictors of IVIG-induced treatment response and disease activity.