Subcutaneous immunoglobulin for treatment of multifocal motor neuropathy

Introduction: Subcutaneous immunoglobulin (SCIg) has been used for treatment of immune neuropathies. Methods: We evaluated the safety and efficacy of 1.53:1 SCIg to intravenous immunoglobulin (IVIg) in individuals receiving <2 g/kg IVIg per month and 1:1 in individuals receiving 2 g/kg per month for treatment of multifocal motor neuropathy (MMN) in an open-label, 6-month trial. Medical Research Council sum score, grip strength, modified Guy's Upper Limb Neurological Disability score, Health Utility Index Quality of Life score, and immunoglobulin levels were evaluated at baseline and at 3 and 6 months. Results: Eleven men and 4 women, aged 31-82 years, were enrolled. Eleven patients completed the program with minor localized reactions and high satisfaction. Three of 6 patients receiving less than 1.53:1 replacement developed intolerable weakness by month 3, and 1 exited after developing erythema and elevated transaminase levels. Conclusion: Patients with MMN tolerate SCIg infusion with maintained strength, but some patients may develop increasing weakness and merit close monitoring. Muscle Nerve54: 856-863, 2016