title: Neuroimaging and biochemical markers in the three variants of primary progressive aphasia.
abstract: OBJECTIVE
  To investigate in variants of primary progressive aphasia (PPA) the association between current clinical and neuroimaging criteria and biochemical/genetic markers at the individual level.
  
  
  METHODS
  Thirty-two PPA patients were classified as non-ﬂuent/agrammatic (nfvPPA), semantic (svPPA), or logopenic variant (lvPPA) or as unclassifiable (uPPA). In all patients, we evaluated the neuroimaging criteria (magnetic resonance imaging and/or single photon emission computed tomography/positron emission tomography) of each variant and studied serum progranulin levels, APOE genotype and Alzheimer's disease (AD)-cerebrospinal fluid (CSF) biomarkers. Cases with a first-degree family history of early-onset dementia were genetically tested.
  
  
  RESULTS
  Ten of 15 (66%) nfvPPA, 5/5 (100%) svPPA and 7/7 (100%) lvPPA patients showed at least one positive neuroimaging-supported diagnostic criterion. All lvPPA and 3/5 (60%) uPPA patients presented AD-CSF biomarkers, which were absent in nfvPPA and svPPA cases. Four (27%) nfvPPA patients had dementia-causing mutations: 2 carried a GRN mutation and 2 the C9ORF72 hexanucleotide expansion.
  
  
  CONCLUSIONS
  There was an excellent association between clinical criteria and neuroimaging-supported biomarkers in svPPA and lvPPA, as well as with AD-CSF biochemical markers in the lvPPA. Neuroimaging, biochemical and genetic findings in nfvPPA were heterogeneous. Incorporating biochemical/genetic markers into the PPA clinical diagnosis would allow clinicians to improve their predictions of PPA neuropathology, especially in nfvPPA and uPPA cases.
authors: Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Barcelona, Spain.
authors: S
authors: S
authors: Gil-Navarro
authors: A
authors: A
authors: Lladó
authors: L
authors: L
authors: Rami
authors: M
authors: M
authors: Castellví
authors: B
authors: B
authors: Bosch
authors: N
authors: N
authors: Bargalló
authors: F
authors: F
authors: Lomeña
authors: R
authors: R
authors: Reñé
authors: N
authors: N
authors: Montagut
authors: A
authors: A
authors: Antonell
authors: J L
authors: JL
authors: Molinuevo
authors: R
authors: R
authors: Sánchez-Valle
mesh_terms: D017668:Age of Onset; D000368:Aged; D000544:Alzheimer Disease / Q000097:blood / Q000523:psychology; D018888:Aphasia, Primary Progressive / Q000378:metabolism / Q000473:pathology* / Q000523:psychology; D001057:Apolipoproteins E / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D015331:Cohort Studies; D042622:DNA Repeat Expansion; D004522:Educational Status; D005260:Female; D005819:Genetic Markers; D014644:Genetic Variation; D006801:Humans; D007091:Image Processing, Computer-Assisted; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging / Q000379:methods*; D009483:Neuropsychological Tests; D000077153:Progranulins; D012959:Socioeconomic Factors; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D001057:Apolipoproteins E; D015415:Biomarkers; C492314:GRN protein, human; D005819:Genetic Markers; D036341:Intercellular Signaling Peptides and Proteins; D000077153:Progranulins