GTPase Regulator Associated with Focal Adhesion Kinase 1 (GRAF1) Immunoglobulin‐Associated Ataxia and Neuropathy. Issue 8 (14th September 2020)

• Record Type: Journal Article
• Authors: Pittock, Sean J.; Alfugham, Nora; O'Connor, Kevin; Hinson, Shannon; Kunchok, Amy; Lennon, Vanda A.; Komorowski, Lars; Probst, Christian; McKeon, Andrew
• Is Part Of: Movement disorders clinical practice. Volume 7:Issue 8(2020)
• Page Start: 904
• Page End: 909
• Publication Date: 2020-09-14
• Subjects: GTPase regulator, ataxia, neuropathy, tissue‐based immunofluorescence, paraneoplastic, GRAF1; Movement Disorders; Movement disorders -- Periodicals; Movement disorders; Periodicals; Periodicals; 616
• DOI: 10.1002/mdc3.13036
• Languages: English
• ISSNs: 2330-1619

Abstract

Abstract: Background: To date, 10 patients with GTPase Regulator Associated with Focal Adhesion Kinase 1/Rho GTPase Activating Protein 26‐Immunoglobulin (GRAF1/ARHGAP26‐IgG) associated neurological disorders have been described, most with ataxia. Objective: To report the clinical, oncological, and radiological associations of GRAF1 autoantibodies. Methods: We identified 17 patients whose serum and/or cerebrospinal fluid IgG was confirmed to target GRAF1/ARHGAP26‐IgG by both tissue‐based immunofluorescence and transfected cell‐based assay. Clinical information was available on 14 patients. Results: The median age at neurological symptom onset was 51 years, and 8 (47%) were men. The predominant clinical features were subacute progressive cerebellar ataxia (13) or peripheral neuropathy (2). Magnetic resonance imaging brain (7 available) showed cerebellar atrophy (4, 1 also cerebrum and brainstem atrophy). Of 7 cerebrospinal fluids available for testing, 5 showed pleocytosis with oligoclonal bands in 3. Squamous cell carcinoma was observed in 3 patients (head and neck [2], lung [1]). Conclusion: GTPase Regulator Associated with Focal Adhesion Kinase 1 autoimmunity manifests commonly with subacute ataxia and cerebellar degeneration with a potential association with squamous cell carcinoma. Peripheral neuropathy may also be encountered. Cases in this series responded poorly to immunotherapy.