Clinical features of Pittsburgh compound-B-negative dementia.

Abstract

BACKGROUND/AIMS:

We previously found that some cases of clinically diagnosed Alzheimer's disease (AD) were rated as Pittsburgh compound B (PiB) negative by amyloid imaging (i.e. cases of PiB-negative dementia). The present study was designed to analyze the clinical features of PiB-negative dementia patients in detail.

METHODS:

Of the 64 cases of clinically diagnosed AD, 14 were rated PiB negative. Eleven of these were further analyzed using CSF biomarker levels and findings from MRI, FDG-PET, (123)I-MIBG myocardial scintigraphy and voxel-based morphometry (VBM).

RESULTS:

When examined by (123)I-MIBG myocardial scintigraphy, the heart/mediastinum ratio was significantly higher in the PiB-negative dementia group than in the dementia with Lewy bodies (DLB) group. Analyses of CSF biomarkers and MRI and FDG-PET findings suggested argyrophilic grain disease (AGD) in 3 cases, frontotemporal lobar degeneration (FTLD) in 3 cases, neurofibrillary tangle-predominant dementia (NFTD) in 1 case, and AD in 2 cases. In the VBM data analysis, the PiB-positive AD group showed significant atrophy of both hippocampi compared with the healthy control group, while the PiB-negative dementia group presented with significant atrophy of the left precuneus.

CONCLUSION:

PiB-negative dementia is unlikely to include DLB, while it most likely includes diseases of tauopathy, such as FTLD, AGD and NFTD. A better understanding of PiB-negative dementia is expected to further improve the accuracy of the clinical AD diagnosis.

• Authors: Jun Takeuchi, Hiroyuki Shimada, Suzuka Ataka, Joji Kawabe, Hiroshi Mori, Kei Mizuno, Yasuhiro Wada, Susumu Shiomi, Yasuyoshi Watanabe, Takami Miki
• Journal: Dementia and geriatric cognitive disorders (Dement Geriatr Cogn Disord) Vol. 34 Issue 2 Pg. 112-20 ( 2012) ISSN: 1421-9824 [Electronic] Switzerland
• PMID: 22947919 (Publication Type: Journal Article)
• Copyright: Copyright © 2012 S. Karger AG, Basel.

Chemical References

• 2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole
• Amyloid beta-Peptides
• Aniline Compounds
• Iodine Radioisotopes
• Radiopharmaceuticals
• Thiazoles
• tau Proteins
• Fluorodeoxyglucose F18

Topics

• Aged
• Aged, 80 and over
• Alzheimer Disease (diagnosis, metabolism)
• Amyloid beta-Peptides (cerebrospinal fluid)
• Aniline Compounds (metabolism)
• Case-Control Studies
• Dementia (diagnosis, metabolism)
• Female
• Fluorodeoxyglucose F18
• Humans
• Iodine Radioisotopes
• Lewy Body Disease (diagnosis, metabolism)
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Myocardial Perfusion Imaging
• Positron-Emission Tomography
• Radiopharmaceuticals
• Thiazoles (metabolism)
• tau Proteins (cerebrospinal fluid)