Infectious Diseases and Their Role in Neuroimmune Disease

Abstract

Recent findings suggest a relationship between a post-infectious immune response and neurologic changes. These changes, manifesting as various neurological symptoms, including memory issues and cognitive alterations, may be linked to a form of post-infectious autoimmunity. We have coined the term “Alzheimer’s of the Immune System,” or AIS, to describe this syndrome and various immune partners that may play a role in this immune dysfunction have been identified. Here, we will discuss several clinical presentations that feed into the hypothesis of infectious-immune axis and its mechanism of action. We propose that these disorders fall under the umbrella of AIS and discuss the role of immuno therapy in their management. First, we consider pediatric acute-onset neuropsychiatric syndrome (PANS), a broad diagnostic criterion created to describe children with severe, sudden onset of neuropsychiatric changes. Research exploring the link between immune dysregulation in PANS and its amelioration with intravenous immunoglobulin treatment strongly suggests the association of PANS with a pro-inflammatory state. Next, we delve into autism spectrum disorder (ASD), characterizing it as a neuroimmune disorder. ASD marked by communication and social skill deficits, as well as repetitive and stereotypical behaviors, is characterized by related but distinct profiles of immune dysregulation, inflammation, and endogenous autoantibodies that persist within the affected individual. Further definition of the role of immune dysregulation in ASD thus necessitates a deeper understanding of the interaction between both the mother’s and child’s immune systems, and their potential role in diagnosis and treatment. Lastly, we discuss post-viral fatigue syndrome in patients who have recovered from SARS-CoV-2 infection as another example of neuroimmune condition recently added to the growing list. Further research is needed to validate our hypothesis of AIS, including large scale randomized control trials of different immuno therapies. By unravelling the infectious-immune axis and its mechanism of action, we equip physicians with valuable tools for identifying optimal forms of treatment and management for these conditions.