title: Cerebrospinal fluid tau protein levels and 18F-fluorodeoxyglucose positron emission tomography in the differential diagnosis of Alzheimer's disease.
abstract: OBJECTIVE
  In this study, we aimed to compare cerebrospinal fluid (CSF) levels of total tau (t-tau), phosphorylated tau (p-tau(181)) and positron emission tomography with (18)F-fluorodeoxyglucose (FDG-PET) in the differential diagnosis of Alzheimer's disease (AD) under clinical conditions.
  
  
  METHODS
  In a cross-sectional, blinded, single-center study, we examined a sample of 75 unselected memory clinic patients with clinical diagnoses of dementia of Alzheimer type (DAT; n = 24), amnestic mild cognitive impairment (MCI; n = 16), other dementias (n = 13) and nondemented controls (n = 22). Discriminative accuracy, sensitivity and specificity were calculated and compared using ROC analyses.
  
  
  RESULTS
  p-tau(181) and FDG-PET were comparable in separating DAT from controls (sensitivity: 67 vs. 79%; specificity: 91% for both) and patients with other dementias (sensitivity: 71 vs. 79%; specificity: 100% for both). The sensitivity of p-tau(181) in differentiating MCI patients from controls was significantly (p < 0.05) superior to that of FDG-PET (75 vs. 44%) at a comparably high specificity (82 vs. 91%); t-tau measures were less accurate in all analyses.
  
  
  CONCLUSIONS
  FDG-PET and CSF p-tau(181) levels are able to discriminate DAT in heterogeneous and unselected samples with a high accuracy. CSF p-tau(181) might be somewhat superior for a sensitive detection of patients with MCI.
authors.affiliation: Department of Psychiatry and Psychotherapy, University Medical Center Mainz, Mainz, Germany. igor.yakushev@uni-mainz.de
authors.forename: Igor
authors.initials: I
authors.lastname: Yakushev
authors.forename: Peter
authors.initials: P
authors.lastname: Bartenstein
authors.forename: Thomas
authors.initials: T
authors.lastname: Siessmeier
authors.forename: Christoph
authors.initials: C
authors.lastname: Hiemke
authors.forename: Armin
authors.initials: A
authors.lastname: Scheurich
authors.forename: Johannes
authors.initials: J
authors.lastname: Lotz
authors.forename: Andreas
authors.initials: A
authors.lastname: Fellgiebel
authors.forename: Matthias J
authors.initials: MJ
authors.lastname: Müller
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000175:diagnosis* / Q000000981:diagnostic imaging; D019540:Area Under Curve; D003072:Cognition Disorders / Q000134:cerebrospinal fluid / Q000175:diagnosis / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008569:Memory Disorders / Q000523:psychology; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D012372:ROC Curve; D019275:Radiopharmaceuticals; D016875:tau Proteins / Q000134:cerebrospinal fluid*
chemical_list: D019275:Radiopharmaceuticals; D016875:tau Proteins; D019788:Fluorodeoxyglucose F18