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Background Two diagnoses to consider in late-onset, slowly progressive sensory neuropathy are anti-MAG neuropathy and CANVAS (Cerebellar Ataxia Neuropathy and Vestibular Apraxia Syndrome).Methods Retrospective case note review of two individuals referred to our centre for advice and management of presumed anti-MAG neuropathy were re-diagnosed with CANVAS with confirmed bi-allelic, pathogenic RFC1 repeat expansions.Results Two females presented initially with distal paresthesia (aged 48 and 65), which spread proximally over several years with an accompanying increasingly unsteady gait. Neither had constitutional symptoms.Both had absent SNAPs with mildly prolonged DMLs (APB 12.2ms (at the elbow)) in one. Anti-MAG antibodies were weakly positive in both patients, and an IgM paraprotein detected in one. One patient had previously been treated with Rituximab.On review one patient reported oscillopsia and both had chronic cough. In both patients their gait was broad based with pronounced ataxia and mild pseudoathetosis, tone was normal, strength full, JPS intact, and VS normalised at ankles bilaterally and costal margins bilaterally respectively. One patient had bilaterally impaired vestibulo-occular reflexes.Clinical features and sub-pathogenic anti-MAG antibody titres led to genetic diagnosis of CANVAS.Conclusion We highlight important positive and negative clinical features to facilitate differentiation of anti-MAG neuropathy and CANVAS.rebecca.johnson131@nhs.net