Purkinje cell (PC) antibody positivity in a patient with autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy.

Here, we describe the case of a patient with autoimmune GFAP astrocytopathy whose CSF was positive for ITPR1-IgG; however, she did not show typical ataxia manifestations or cerebellar lesions on her MRI scan. This suggests that ITPR1-IgG is not pathogenic, and the positivity of this antibody in CSF is probably associated with the presence of autoimmune inflammation.