Serum heart-type fatty acid-binding protein and cerebrospinal fluid tau: marker candidates for dementia with Lewy bodies.
BACKGROUND
The measurement of biomarkers in cerebrospinal fluid (CSF) has gained increasing acceptance in establishing the diagnosis of some neurodegenerative diseases. Heart-type fatty acid-binding protein (H-FABP) was recently discovered in CSF and serum of patients with neurodegenerative diseases.


OBJECTIVE
We investigated H-FABP in CSF and serum alone and in combination with CSF tau protein to evaluate these as potential biomarkers for the differentiation between dementia with Lewy bodies (DLB) and Alzheimer's disease (AD).


METHODS
We established H-FABP and tau protein values in a set of 144 persons with DLB (n = 33), Parkinson disease with dementia (PDD; n = 25), AD (n = 35) and nondemented neurological controls (NNC; n = 51). Additionally, serum H-FABP levels were analyzed in idiopathic Parkinson disease patients without evidence of cognitive decline (n = 45) using commercially available enzyme-linked immunosorbent assays. We calculated absolute values of H-FABP and tau protein in CSF and serum and established relative ratios between the two to obtain the best possible match for the clinical working diagnosis.


RESULTS
Serum H-FABP levels were elevated in DLB and PDD patients compared with NNC and AD subjects. To better discriminate between DLB and AD, we calculated the ratio of serum H-FABP to CSF tau protein levels. At the arbitrary chosen cutoff ratio > or =8 this quotient reached a sensitivity of 91% and a specificity of 66%.


CONCLUSIONS
Our results suggest that the measurement of CSF tau protein, together with H-FABP quantification in serum and CSF, and the ratio of serum H-FABP to CSF tau protein represent marker candidates for the differentiation between AD and DLB.
Mollenhauer
Brit
B
Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Institutes of Medicine, 77 Avenue Louis Pasteur, Boston, MA 02115, USA. bmollenhauer@rics.bwh.harvard.edu
Steinacker
Petra
P
Bahn
Erik
E
Bibl
Mirko
M
Brechlin
Peter
P
Schlossmacher
Michael G
MG
Locascio
Joseph J
JJ
Wiltfang
Jens
J
Kretzschmar
Hans A
HA
Poser
Sigrid
S
Trenkwalder
Claudia
C
Otto
Markus
M
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood / Q000134:cerebrospinal fluid / Q000175:diagnosis; D015415:Biomarkers / Q000032:analysis / Q000097:blood / Q000134:cerebrospinal fluid; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D000074026:Fatty Acid Binding Protein 3; D050556:Fatty Acid-Binding Proteins / Q000032:analysis / Q000097:blood*; D005260:Female; D006801:Humans; D020961:Lewy Body Disease / Q000097:blood* / Q000134:cerebrospinal fluid* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000097:blood / Q000134:cerebrospinal fluid / Q000175:diagnosis; D011237:Predictive Value of Tests; D015983:Selection Bias; D016875:tau Proteins / Q000032:analysis / Q000134:cerebrospinal fluid*
D015415:Biomarkers; C493408:FABP3 protein, human; D000074026:Fatty Acid Binding Protein 3; D050556:Fatty Acid-Binding Proteins; D016875:tau Proteins