title: Classification and pathology of primary progressive aphasia.
abstract: OBJECTIVE
  We aimed to determine the extent to which patients with progressive language impairment conform to 2011 primary progressive aphasia (PPA) classification and to examine clinicopathologic correlations within PPA variants.
  
  
  METHODS
  Sixty-two consecutive patients with pathologically confirmed dementia who presented clinically with aphasia were identified. Patients with insufficient clinical information were excluded. PPA classifications were applied to anonymized clinical data taken from patients' initial assessment by raters who were blinded to clinical and pathologic diagnosis.
  
  
  RESULTS
  The final cohort comprised 52 patients, 30 of whom met basic PPA criteria. Twenty-five patients met one of the 3 PPA classifications (13 logopenic, 8 nonfluent/agrammatic, and 4 semantic). Five patients did not meet the criteria for any of the PPA variants. All patients who met semantic variant PPA and 75% of patients who met nonfluent/agrammatic variant PPA classifications had frontotemporal lobar degeneration spectrum pathology. Pathologies were heterogeneous in patients who met logopenic variant PPA criteria (46% Alzheimer disease [AD], 8% AD mixed with dementia with Lewy bodies, 23% frontotemporal lobar degeneration, and 23% other).
  
  
  CONCLUSIONS
  The 2011 PPA recommendations classify a large proportion of patients who meet basic PPA criteria. However, some patients had aphasic syndromes that could not be classified, suggesting that the 2011 recommendations do not cover the full range of PPA variants. Classification of semantic variant PPA provides a good prediction of underlying pathology. Classification of logopenic variant does not successfully differentiate PPA due to AD from PPA due to other pathologies.
authors.affiliation: From the Manchester Academic Health Sciences Centre (J.M.H., C.G., J.C.T., A.M.T.R., D.N., D.d.P., P.P., D.M.A.M., J.S.S., M.J.), Cerebral Function Unit, Greater Manchester Neuroscience Centre, Salford Royal NHS Foundation Trust, Salford; and Institute of Brain, Behaviour and Mental Health (J.M.H., D.N., D.M.A.M., J.S.S., M.J.), University of Manchester, UK.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Harris
authors.forename: Claire
authors.initials: C
authors.lastname: Gall
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Thompson
authors.forename: Anna M T
authors.initials: AM
authors.lastname: Richardson
authors.forename: David
authors.initials: D
authors.lastname: Neary
authors.forename: Daniel
authors.initials: D
authors.lastname: du Plessis
authors.forename: Piyali
authors.initials: P
authors.lastname: Pal
authors.forename: David M A
authors.initials: DM
authors.lastname: Mann
authors.forename: Julie S
authors.initials: JS
authors.lastname: Snowden
authors.forename: Matthew
authors.initials: M
authors.lastname: Jones
mesh_terms: D017668:Age of Onset; D000368:Aged; D000544:Alzheimer Disease / Q000150:complications / Q000473:pathology; D018888:Aphasia, Primary Progressive / Q000145:classification* / Q000209:etiology / Q000473:pathology; D015331:Cohort Studies; D003704:Dementia / Q000145:classification* / Q000209:etiology / Q000473:pathology; D005260:Female; D057174:Frontotemporal Lobar Degeneration / Q000150:complications / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged