Objective:

To describe patients with progressive apraxia of speech (PAOS) caused by underlying Pick’s Disease.

Background:

With progression, most PAOS patients develop atypical parkinsonian features suggestive of corticobasal syndrome (CBS) or progressive supranuclear palsy (PSP), and most autopsy confirmed cases have had an underlying 4-repeat tauopathy.

Design/Methods:

We reviewed patients enrolled in the Neurodegenerative Research Group’s ongoing studies on speech and language disorders and identified those with PAOS who had autopsy confirmed Pick’s disease.

Results:

Three patients were identified, all women. P1 reported onset of speech problems at age 54, with study enrollment at age 60. She had phonetic AOS and mild cognitive impairment (MCI), but no aphasia, parkinsonism, or behavioral changes. Over the next 2 years she developed personality and cognitive changes consistent with behavioral variant frontotemporal dementia (bvFTD), passing away at age 64. P2 had speech changes starting at age 47, but by enrollment at 49 met criteria for bvFTD with phonetic AOS. She developed agrammatism but no parkinsonism or limb apraxia and passed away at 53. P3 had speech changes at 58 and enrolled at age 60, at which time she had phonetic AOS and MCI. She had no follow up visits and died at age 63. Neuroimaging in P1 and P2 showed inferior frontal, insular, and anterior-medial temporal involvement, primarily on the right, as well as superior prefrontal involvement. In contrast, P3 had bilateral premotor but no temporal involvement.

Conclusions:

Our findings highlight that Pick’s can present with PAOS. In contrast to PAOS caused by 4-repeat tau, our cases did not develop motoric impairment suggestive of PSP or CBS. All had phonetic AOS, which is more common among younger PAOS patients. Two of the three had prominent temporal hypometabolism, which is unusual for PAOS. These findings may prove useful in identifying Pick’s as a cause of PAOS.