The extremely variable spectrum of neurologic characteristics reported in up to 30% of CTLA4 carriers from childhood to late adulthood, includes headache and seizures (as leading symptoms), encephalitis/encephalomyelitis with cerebral perivascular lymphocytic infiltration, nausea, aphasia, visual impairment, ventriculomegaly, and slowly progressive cognitive deterioration (Table 1) [5,14,15,28,29,30]. Here, CTLA4 is linked to viral encephalitis.