Autoimmune cerebellar ataxia : overview

Abstract

Autoimmune cerebellar ataxia (ACA) is a group of central nervous system disorders characterized by isolated or predominant cerebellar dysfunction induced by an immune–mediated mechanism. ACA diagnosis is challenging and ACA patients can be misdiagnosed with degenerative neurological diseases. Approximately 30 anti–neuronal antibodies associated with ACA have been reported. Although these antibodies are useful diagnostic markers of ACA, it is impossible to investigate them all at the same time. Moreover, ACA patients can possess antibodies for unknown antigens. Tissue–based immunofluorescence is a useful method for screening antibodies. However, if the target antigens of a patient's antibodies are unknown, a diagnosis of ACA should be determined using combined clinical data and the findings of brain magnetic resonance imaging and cerebrospinal fluid examinations. Immunotherapies and anti–tumor therapies are needed to treat ACA patients. Although responses to immunotherapies depend on the kinds of anti–neuronal antibodies possessed by patients, early initiation of therapies is important. The establishment of clinical diagnostic criteria and novel therapies for ACA are required.