Sporadic Progressive Ataxia and Palatal Tremor (PAPT) is a rare syndrome characterized by symptomatic palatal tremor and slowly progressive cerebellar ataxia. To date, there has been only 1 autopsy report, which described a novel 4-repeat tauopathy with hypertrophic olivary degeneration and tau-positive inclusions in olivary neurons and dystrophic neuritic processes termed glomeruloid bodies. We report 2 further autopsy cases.

Case 1 is a 77-year-old man who presented with blurred vision and subsequently developed ataxia and gait instability. Dysarthria and palatal tremor appeared later. MRI showed T2 hyperintensity of the pons and bilateral inferior olives.

Case 2 is an 89-year-old man who presented with dysarthria and progressed to cerebellar ataxia and palatal tremor. 9 years into his disease course, his palatal tremor spontaneously resolved. MRI showed T2 hyperintensity in the bilateral olives, left midbrain, and right dentate nucleus.

Consistent findings in both cases included bilateral hypertrophic vacuolar olivary degeneration accompanied by tau-positive neuronal inclusions and glomeruloid bodies, along with tauopathy in the pons and midbrain. Cerebellar cortical degeneration was extensive, but involvement of the dentate was minimal. Tau and TDP-43 negative basophilic neuronal cytoplasmic inclusions in the olive and Purkinje cells were also a feature.