Intravenous immunoglobulin as a therapy for autoimmune conditions.

Intravenous immunoglobulin (IVIg) is a medical preparation used as replacement therapy for patients with immunodeficiencies. Over time, IVIg's anti-inflammatory and immunomodulatory effects have been recognized, which have led to the approval of this therapy in the treatment of various pathologies, such as Kawasaki disease, immune thrombocytopenia, and Guillain-Barré syndrome. There are numerous studies in the literature regarding the off-label use of IVIg in the treatment of autoimmune diseases (e.g. myositis and vasculitis), and hematological disorders. Since the role of immunoglobulins in fields other than replacement therapy is now consolidated, in this study we carried out a review of the literature to evaluate the main uses of IVIg therapy. We have focused our attention on the treatment of autoimmune, neurological, hematological, dermatological and pediatric diseases. Furthermore, our analysis of the literature also extended to the potential use of IVIg as an adjuvant treatment of long COVID-19. From our analysis, we found consistent data about IVIg's effectiveness in treating numerous clinical conditions. Treatment with IVIg represents a second-line approach or a valid adjuvant to standard therapies capable of positively influencing the clinical course of many pathologies and reducing or avoiding side effects of standard therapies, with a good safety profile.