Clinical Reasoning: A 48-Year-Old Man With Spasticity and Progressive Ataxia.

We present the case of a 48-year-old man who was referred to the movement disorders clinic for 10 years of progressive slurred speech, spasticity, limb incoordination, and wide-based gait. Extensive neurological workup was inconclusive, including serum and CSF testing, neuroimaging, EMG/NCS, exome sequencing, and mitochondrial testing. An ataxia repeat expansion panel ultimately revealed the final diagnosis. In this report, we review the clinical characteristics of a rare, late-onset, autosomal recessive cerebellar ataxia and discuss the importance of pursuing targeted gene testing to avoid diagnostic delays, especially as new treatments for this and other genetic diseases become available.