Evaluation of the risk factors predicting thrombotic complications associated with intravenous immunoglobulin therapy in neuroimmunological diseases.

Intravenous immunoglobulin (IVIg) therapy is increasingly used for various conditions that include neuroimmunological disorders, such as chronic inflammatory demyelinating polyneuropathy, Guillain-Barré syndrome, myasthenia gravis, and myositis. Although IVIg therapy is considered a relatively safe treatment, previous studies have reported thrombotic complications associated with IVIg (TCI). The precise mechanisms and associated risk factors have not been fully elucidated to date. Three of our patients experienced TCI. Although immobility is one of the most common risk factors for venous thrombosis, all three patients could walk without assistance; their modified Rankin Scale (mRS) scores were 2. We assessed the clinical characteristics of these patients and compared their data with that of 65 patients who received IVIg from the years 2000 to 2019 without experiencing TCI to identify associated risk factors. The frequency of TCI among patients with neuroimmunological disorders at our hospital was 4.4% (3/68 patients). There were no significant differences between the patients with and without TCI regarding their mean age (69.7 vs 58.0 years, p = 0.244), percentage of females (66.7% vs 45.6%, p = 0.588), mean body mass index (22.67 vs 22.16, p = 0.878), mean mRS score (2.22 vs 2.00, p = 0.658), and use of oral prednisolone (66.7% vs 13.8%, p = 0.0658). Interestingly, the D-dimer levels of two of the patients with TCI were not elevated before treatment. Sixteen patients received anticoagulant therapy during IVIg treatment, and none suffered from TCI. As our analysis suggested, it might be important to monitor D-dimer levels before and after IVIg to help prevent and detect TCI.