Ataxia as forme fruste of opsoclonus myoclonus ataxia syndrome

Since the child had a response to oral corticosteroids, immune-mediated ataxia was considered. A diagnostic criteria has been described, and 3 out of 4 criteria should be present for the diagnosis of OMAS: a) opsoclonus; b) myoclonus or ataxia; c) behavioral change or sleep disturbances; d) neuroblastoma. Ethical approval An informed consent form was signed by the parents of the patient to approve the use of patient information or material for scientific purposes.