Diagnostic criteria The following diagnosis criteria were defined by Mesulam: * As opposed to having followed trauma to the brain, a patient must show an insidious onset and a gradual progression of aphasia, defined as a disorder of sentence and/or word usage, affecting the production and comprehension of speech. * The disorder in question must be the only determinant on functional impairment in the activities of the patient’s daily living. * On the basis of diagnostic procedures, the disorder in question must be unequivocally attributed to a neurodegenerative process. Whether or not PPA and other aphasias are the only source of cognitive impairment in a patient is often difficult to assess because: 1) as with other neurologically degenerative<unk> s, such as<unk> 's<unk> , there are currently no reliable non-invasive diagnostic tests for aphasias, and thus neuropsychological assessments are the only tool physicians have for diagnosing patients; and 2) aphasias often affect other, non-language portions of these neuropsychological tests, such as those specific for memory. Classification In 2011, the classification of primary progressive aphasia was updated to include three clinical variants. Patients must first be diagnosed with PPA, and then divided into variants based on speech production features, repetition, single- word and syntax comprehension, confrontation naming, semantic knowledge, and reading/spelling. In the classical Mesulam criteria for primary progressive aphasia, there are two variants: a non-fluent type progressive nonfluent aphasia (PNFA) and a fluent type semantic dementia (SD). A third variant of primary progressive aphasia, logopenic progressive aphasia (LPA) was then added, and is an atypical form of<unk> 's<unk> . For PNFA, The core criteria for diagnosis includes agrammatism and slow, and labored speech. Inconsistent speech sound errors are also very common, including distortions, deletions, and insertions. In terms of comprehension, there are deficits in syntax and sentence comprehension due to grammatical complexity, but single- word and object comprehension is relatively maintained. The second variant, SD, presents with deficits in single-word and object comprehension. Naming impairments can be severe, specially for low-frequency objects, and can eventually lead to a more widespread semantic memory deficiency over time. The ability to read and write can also be impaired if there are irregularities between pronunciation and spelling. However, repetition and motor speech is relatively preserved. The logopenic variant involves impairments in word retrieval, sentence repetition, and phonological paraphasias, comparable to conduction aphasia. Compared to the semantic variant, single word comprehension and naming is spared, however, sentence comprehension presents difficulty because of length and grammatical complexity. Speech will include incomplete words, hesitations preceding content words, and repetition. However, these PPA subtypes differ from similar aphasias, as these subtypes do not occur acutely following trauma to the brain, such as following a stroke, due to differing functional and structural neuroanatomical patterns of involvement and the progressive nature of the<unk> .
symptom of Alzheimer's disease
medical cause of Dementia
symptom of Lesch–Nyhan syndrome
symptom of Amyotrophic lateral sclerosis
symptom of Multiple sclerosis
symptom of Brain tumor
symptom of Myotonic dystrophy
symptom of Narcolepsy