Subcutaneous immunoglobulin in polymyositis and dermatomyositis: a novel application.

OBJECTIVES: To describe the feasibility and safety of subcutaneous immunoglobulin (SCIg) in polymyositis (PM) and dermatomyositis (DM). METHODS: Since 2009, we used SCIg to treat patients with severe idiopathic myositis (4 with DM, 3 with PM), diagnosed according to the Bohan and Peter's criteria. SCIg (Vivaglobin®; CSL Behring) was administered by a programmable pump at the patient's usual IVIg monthly dose fractioned into equal doses given subcutaneously at weekly intervals. A standardized protocol was used to evaluate patients and to assess disease activity, treatment response and quality of life. RESULTS: Seven female patients were studied. All were Caucasians, with a median age of 53 years and a median disease duration of 72 months. The median follow-up period was 14±4 months. During treatment period, no relapse of the disease occurred. All patients showed a favourable clinical response and reported a good tolerance to the treatment with an improved quality of life. CK serum levels decreased over time with a concomitant improvement in MRC and Rankin modified scores. Three patients were able to discontinue the immunosuppressant and all to reduce the daily maintenance prednisone dose. CONCLUSIONS: Our experience demonstrates the beneficial effect and the safety of SCIg administration in active and refractory inflammatory myopathies.