[New therapies in multiple sclerosis]. / Actualités thérapeutiques dans la sclérose en plaques.

Due to the autoimmune nature of multiple sclerosis (MS), the current disease modifying treatments aim at reducing the immune system activity or at interfering with it. Immune modulators from the interferon Beta and glatiramer acetate families are widely used as first line treatments. They often prove sufficient for moderately active forms of the disease. For more active forms, powerful immunosuppressants such as mitoxantrone or a monoclonal antibody (natalizumab), selective inhibitor of the T cell adhesion molecule on the cerebral endothelium, are used. Several new promising oral medications should be added to this therapeutic arsenal shortly. Most of the times, these various treatments are already effective for preventing relapses. However, they remain rather ineffective for progression which is the second clinical constituent of the disease. Improvements are urgently needed in this area.

Metabotropic glutamate receptor type 1 autoantibody-associated cerebellitis: a primary autoimmune disease?

OBJECTIVES: To report the third case of subacute cerebellar ataxia associated with metabotropic glutamate receptor type 1 autoantibodies (mGluR1-Abs), an uncommon syndrome known to be part of the group of paraneoplastic cerebellar degeneration syndromes linked to antineuronal antibodies and previously reported in only 2 other patients with long-term remission of Hodgkin lymphoma, and to discuss the underlying immunopathogenesis. DESIGN: Case report. SETTING: University hospital. PATIENT: A 50-year-old woman admitted for acute severe isolated static and kinetic cerebellar syndrome. Magnetic resonance imaging of the brain showed diffuse abnormal hyperintensity in the whole cerebellum on fluid-attenuated inversion recovery and diffusion sequences. RESULTS: Results of the biological workup were negative for general inflammation, vitamin deficiency, and bacterial and viral infections. Immunohistochemical analysis of the serum and cerebrospinal fluid of the patient demonstrated staining for Purkinje cell bodies and the molecular layer of the cerebellum. Finally, mGluR1-Abs were detected in serum and cerebrospinal fluid by a cell-based assay. Complete clinical examination, thoracoabdominal-pelvic computed tomography, and whole-body fludeoxyglucose F 18-positron emission tomography failed to show any underlying tumor, including Hodgkin lymphoma. The disease was stabilized after a course of intravenous immunoglobulins and continuous mycophenolate mofetil treatment during a follow-up of 40 months. CONCLUSIONS: Cerebellitis associated with mGluR1-Abs should be considered in the differential diagnosis of patients with subacute cerebellar ataxia. This first case without any tumor found suggests a possible idiopathic autoimmune rather than a paraneoplastic mechanism. In consideration of this possible primitive autoimmune ataxia involving the directly pathogenic mGluR1-Abs, immunoactive therapy should be initiated as early as possible.