Clinical Features and Neuroimaging Findings of Neuropil Antibody-Positive Idiopathic Sporadic Ataxia of Unknown Etiology

Idiopathic sporadic ataxia (ISA) is the clinical term for nonfamilial ataxia with adult-onset and a slowly progressive course. However, immune-mediated cerebellar ataxia cannot be completely excluded from ISA. The current study investigated the neuropil antibodies against cell-surface antigens and clarified the clinical features and neuroimaging findings of patients with these antibodies. Using tissue-based immunofluorescence assays (TBAs), we examined antibodies against the cerebellum in serum samples from 67 patients who met the ISA diagnostic criteria, including 30 patients with multiple system atrophy with predominant cerebellar features (MSA-C) and 20 patients with hereditary ataxia (HA), and 18 healthy control subjects. According to the TBA results, we divided subjects into three groups: subjects positive for neuropil antibodies, subjects positive for intracellular antibodies only, and subjects negative for antibodies. We compared clinical features and neuroimaging findings in ISA patients among these three groups. The prevalence of neuropil antibodies in ISA (17.9%) was significantly higher than that in MSA-C (3.3%), HA (0%), or healthy subjects (0%). The neuropil antibody-positive ISA patients showed pure cerebellar ataxia more frequently than the other ISA patients. Two neuropil antibody-positive patients showed significant improvement of cerebellar ataxia after immunotherapy. We detected neuropil antibodies in 17.9% of ISA patients. Characteristic clinical features of neuropil antibody-positive ISA patients were pure cerebellar ataxia. Some cases of neuropil antibody-positive ISA responded to immunotherapy.

Gluten Sensitivity - A Potentially Reversible Cause of Progressive Cerebellar Ataxia and Myoclonus - A Case Report

Gluten sensitivity is an umbrella term used for diverse clinical manifestations occurring as a result of abnormal immunological reactivity to dietary gluten in genetically susceptible individuals. Celiac disease is the most well-known but not the only manifestation of gluten sensitivity. Myoclonus with Ataxia is a rare manifestation of gluten sensitivity and should be considered in the differential diagnosis of all patients with idiopathic sporadic ataxia. The presence of gluten-related immune markers in normal population however complicates the reliable diagnosis of gluten related neurological disorders and clinical improvement on gluten free diet can serve as a diagnostic tool for this disease. We report a case of sporadic progressive cerebellar ataxia with myoclonus with positive antigliadin antibodies, which improved with a trial of gluten free diet. This case highlights an important diagnostic and therapeutic principle in management of late onset idiopathic ataxia.