Infection-Induced Autoimmune Encephalopathy: Treatment with Intravenous Immune Globulin Therapy. A Report of Six Patients

Abstract

Objective: To present illustrative patients with infection-induced autoimmune encephalopathy (IIAE) who manifest symptoms and signs of pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) and are successfully treated with an anti-infective and immune modulatory protocol. Methods: Six children age 5 to 17 years with the diagnosis of IIAE associated with various infections and comorbid conditions including humoral immunodeficiency and Autism Spectrum Disorder (ASD) are described. Pertinent literature from 1958 to the present is reviewed. Antimicrobial and high dose (1 gram per kilogram total body weight) intravenous immune globulin (IVIg) therapy was administered every 8 weeks according to an established anti-infective and immune modulatory protocol. Informed consent by the parents and legal authorization was obtained in all cases. Neuroradiological testing was not performed in any of the cases. Results: The combination of antimicrobial medication followed by IVIg in this cohort was well-tolerated leading to improvement in symptoms and signs of IIAE allowing tapering or discontinuation of maintenance medications. Conclusion: IVIg is a safe and beneficial therapy in IIAE, PANDAS and ASD impacting favorably on underlying humoral immune deficiency and infectious-induced CNS autoimmunity in this small and highly selected cohort. The present findings are awaiting further replication by other investigators and should be further explored relative to the optimal dose and duration of therapy.