The Role of Neuroimaging in a Fragile X Carrier with only Dementia and Perypheral Neuropathy (P2.1-019)

Objective: We report a case of FMR1 premutation with only cognitive deficit and peripheral neuropathy with major radiological features. Background: FXTAS is caused by premutation alleles in FMR1 gene which is associated with a variety of manifestations and phenotypes, and the precise relationship between these mutations, the symptoms that carriers experience throughout life, and the risk of developing FXTAS is not clear. FXTAS is a significant cause ataxia in aging men, and is the most common known single-gene form of tremor and ataxia, and perhaps also of dementia, in the older adult population. The premutation is defined as 55–200 CGGs. Design/Methods: Not applicable Results: 61-year-old man with a 2-year history of burning and tingling in his feet with progressive weakness and sexual impotence. He had no cerebellar ataxia or tremor in medical exam. His Mini-Mental State Examination was 23/30. Clinical history of well controlled diabetes mellitus. Brain MRI showed restricted diffusion in splenus and sharpening of the corpus callosum. Symmetric signal change of middle cerebellar peduncles. T2/FLAIR hyperintensity in the deep/periventricular white matter as well as in the corpus callosum. The aforementioned parenchymal changes are not specific but raised the possibility of neurodegenerative diseases. A genetic study was performed and found expansion of a CGG repeat to 135 copies in FMR1. Conclusions: An interesting and unusual observation in this case was the importance of neuroimaging for diagnose in patient that doesn’t had clinical criteria for FXTAS. The wide range of clinical and neuropsychological manifestations of this syndrome turns it difficult to closure with just clinical manifestations. White matter lesions in middle cerebellar peduncle and in splenium of the corpus callosum was extremely important to think and seek FMR1 premutation. The presence of the MCP sign in patients with FXTAS is correlated with more severe cognitive deficits and a longer history of symptoms. Disclosure: Dr. Guimaraes de Queiroz has nothing to disclose. Dr. Ferreira Lima has nothing to disclose. Dr. Teixeira has nothing to disclose. Dr. Mantelatto Bonsi has nothing to disclose. Dr. Freitas has nothing to disclose. Dr. Escorcio-Bezerra has nothing to disclose. Dr. Baeta has nothing to disclose.