Ruggero Bacchin, Matteo Salgarello, Michela Trentin, Giampietro Zanette, Stefano Tamburin
ABSTRACT: Fragile X-associated tremor/ataxia syndrome (FXTAS) is a rare movement disorder caused by a 55-to-200 CGG-trinucleotide expansion premutation in the FMR1 gene. Core diagnostic criteria are tremor, ataxia, and T2-weighted hyperintensity of the middle cerebellar peduncles on MRI, but FXTAS encompass a broad spectrum of neurological symptoms. FXTAS pathophysiology is largely unknown, and some animal models and neuropathology findings suggest possible overlap with Alzheimer disease. We report the combined PET imaging of a genetically confirmed FXTAS patient, presenting reduced temporal-frontal 18F-FDG uptake, and pathological cortical deposition of amyloid to 18F-flumetamol PET scan. This report may offer clues to FXTAS pathophysiology.
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