Memory also is impaired, but this is not as distinguishing as the frontal lobe or language features. The clinical pattern reflects the topographic pattern of atrophy, often visible radiographically, with asymmetric frontotemporal atrophy. Throughout the course of the disease, signs and symptoms of MND also progress. Limb weakness and dysphagia eventually become disabling, although some patients have a primarily bulbar pattern of weakness with relative sparing of limb strength. Recently, consensus clinical criteria detailing core and supportive features for FTD syndromes were published.
Memory is impaired, but less consistently in the mild stages.
Clinical signs of MND usually follow or accompany dementia onset. MND signs include bulbar weakness with dysarthria and dysphagia, limb weakness, muscle wasting and fasciculations, and, of greatest concern, dyspnea. A minority of patients has a family history, but this overlap syndrome may be related to other neurodegenerative overlap syndromes that include variable degrees of dementia, MND, and parkinsonism. Familial cases of this type are linked to a mutated region of chromosome 17, which contains the tau gene. Obtain typical blood studies, thyroid function tests, vitamin B12 and folate levels, and Venereal Disease Research Laboratory test.