Agraphia in bulbar-onset amyotrophic lateral sclerosis: not merely a consequence of dementia or aphasia.
The clinical significance and characteristics of writing errors in bulbar-onset amyotrophic lateral sclerosis (ALS) are not clear. We retrospectively investigated writing samples in 19 patients with bulbar-onset ALS without preceding extra-motor symptoms. Co-development of dementia and/or aphasia was also explored and single photon emission computed tomography (SPECT) images of the brain were reviewed. As a result, a high prevalence of writing errors (15 of the 19 patients) was found. Of note were isolated writing errors with neither dementia nor aphasia verified in 2 patients whose dysarthria was mild enough to evaluate spoken language. The remaining 13 patients also showed agraphia, but either dysarthria was too severe to evaluate aphasia or frontotemporal dementia (FTD)-like features co-existed. Of these patients, one who initially lacked dementia subsequently developed FTD-like features. The frequent writing errors were omission or substitution of kana letters and syntactic errors. SPECT images showed bilateral or left-side dominant hypoperfusion in the frontotemporal lobes as a consistent feature. These results show that patients with bulbar-onset ALS frequently exhibit agraphic writing errors and that these are not merely consequences of dementia or aphasia. However, these writing errors may indicate the involvement of frontotemporal language-related areas beyond the primary motor cortex.
Ichikawa
Hiroo
H
Department of Neurology, Showa University School of Medicine, Shinagawa-ku, Tokyo, Japan. h ichikawa0527@yahoo.co.jp
Takahashi
Nobuyoshi
N
Hieda
Soutaro
S
Ohno
Hideki
H
Kawamura
Mitsuru
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000381:Agraphia / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D000690:Amyotrophic Lateral Sclerosis / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D001037:Aphasia / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D001921:Brain / Q000000981:diagnostic imaging; D003704:Dementia / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D004401:Dysarthria / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013064:Speech Disorders; D015899:Tomography, Emission-Computed, Single-Photon