An atypical course of a 71-year old man with right arm weakness and ataxia: Expert commentary

Abstract

Dr Khemani and colleagues have presented a diagnostically challenging case of a sporadic, adult onset ataxia (SAOA) syndrome resembling Multiple System Atrophy cerebellar type (MSA-C), with an atypical presentation of focal amyotrophy, eventually diagnosed as spinocerebellar ataxia type 3 (SCA3) [ [1] Khemani P. Elliott M. Levine T. An Atypical Clinical Course of a 71-Year-Old Man with Right Arm Weakness and Ataxia. Parkinsonism Relat Disord, 2022 Abstract Full Text Full Text PDF Scopus (0) Google Scholar ]. The patient had presented elsewhere three years prior, with a Miller Fisher syndrome (MFS) associated with an elevated antiGQ1b antibody titer. However, as the patient had become wheelchair bound over the subsequent three years, the initial diagnosis of MFS is perhaps questionable. When evaluating ataxic disorders, it is important to establish the disease onset and course accurately. As the patient had a progressive cerebellar syndrome, the possible causes could be categorized broadly as: primary autoimmune (paraneoplastic or non-paraneoplastic); or neurodegenerative (sporadic or genetic). Primary autoimmune cerebellar ataxia encompassing paraneoplastic ataxia syndromes, and immune-mediated ataxias (gluten ataxia and anti-GAD65 ataxia) may present insidiously, with accumulating disability especially if timely and appropriate immunosuppressive therapies are not instituted [ [2] Hadjivassiliou M. Graus F. Honnorat J. Jarius S. Titulaer M. Manto M. Hoggard N. Sarrigiannis P. Mitoma H. Diagnostic criteria for primary autoimmune cerebellar ataxia-guidelines from an international task force on immune-mediated cerebellar ataxias. Cerebellum. 2020; 19: 605-610 Crossref PubMed Scopus (35) Google Scholar ].