A Japanese Patient With Progressive Word Deafness and Logoclonia

Primary progressive aphasia (PPA) is classified into several types. However, syndromes that do not belong to these typical types of PPA have been reported, such as cases where only progressive apraxia of speech (AOS) is present in the early stages of the disease. Moreover, there have been a few case reports of patients with progressive word deafness complicated with logoclonia as a speech disorder. Herein, we report a case of degenerative disease with phonological paraphasia, AOS, impaired speech sound cognition, and logoclonia with disease progression. The written language comprehension of the patient was superior to that of spoken language, and she could communicate in writing. She was neurologically normal; had no apraxia, agnosia, or memory impairment; and was independent in activities of daily living. Although she had moderate hearing loss, her speech-related hearing loss was disproportionately high. In analyses of brain imaging, dilation of the left Sylvian fissure, atrophy, and hypoperfusion of the superior temporal gyrus were prominent, and hypoperfusion of the left lateral frontal lobe was observed. Cerebrospinal fluid examination suggested that Alzheimer's disease (AD) pathology was unlikely, and decreased uptake was observed on a dopamine-active transporter scan. Word deafness was thought to be the most likely cause of the dissociation between spoken and written language in our patient. Our case and previous studies suggested that there is a syndrome presenting word deafness and speech movement disorders among patients with progressive communication disorders as a different entity from PPA. Although patients with this syndrome may experience agrammatism, inner language disorders are generally not as severe, and disorders in areas closer to the primary area, such as the motor and auditory areas, as well as cortical and subcortical disorders, are involved in this syndrome.