Table 2.

Criteria for PPA and its subtypes

Criteria for the Root Diagnosis of PPA

Presence of aphasia determined by abnormality of word-finding, word comprehesion, word-order or other aspects of grammar. This can be determined by clinical examination or abnormal scores in batteries such as the WAB or the BDAE. Isolated impairments of speech alone (e.g., dysarthria, apraxia of speech, aphemia) do not qualify The disorder is progressive. The aphasia is primary in the sense that it emerges in relative isolation and becomes the chief impediment to customary daily living activities during the initial stages (1–2 yrs) of the disease. Neurodiagnostics do not reveal an etiology for the aphasia other than neurodegeneration.

Criteria for PPA-G (agrammatic variant):

Descriptive: The central feature is an abnormality of syntax (word-order) or some other aspect of grammar in spoken or written language in the presence of relatively preserved single word comprehension. Fluency is usually impaired and speech is usually effortful and hesitant.

Quantitative: NAT <60%, PPVT ≥60%.

Criteria for PPA-S (semantic variant):

Descriptive:The central feature is an abnormality of single word comprehension in the presence of relatively preserved grammar and fluency. Output is circumlocutory, occasionally uninformative and frequently paraphasic. Naming is severely impaired.

Quantitative: PPVT <60%, NAT ≥60%.

Criteria for PPA-L (logopenic variant):

Descriptive: The central feature is intermittent word-finding hesitations and phonemic paraphasias. Naming is impaired but not as severely as in PPA-S and improves upon phonemic cueing. Repetition may be impaired. Fluent output in casual conversation can alternate with dysfluent speech, which emerges when the patient needs to convey precise information and cannot use circumlocution. Spelling can be impaired

Quantitative: PPVT and NAT are both ≥60%.

Criteria for PPA-M (mixed):

Descriptive: Combination of agrammatism with comprehension deficit, usually accompanied by poor fluency and frequent paraphasias.

Quantitative: PPVT and NAT are both < 60%.