Joined: Fri Aug 11, 2006 1:46 pm
Location: SF Bay Area (Northern CA)
FTD mimicking DLB (Mayo Rochester study, 6 patients)
We have one person in our local support group whose diagnosis has changed from DLB to FTD. Apparently when "FTD patients" have motor symptoms and psychosis, it is difficult to determine if they have FTD or DLB.
This small study from Mayo Rochester looks at 6 patients who "met published consensus criteria for a diagnosis of both FTD and DLB (5 probable and 1 possible). Clinical symptoms of FTD included personality and behavioral changes, whereas those suggestive of DLB included Parkinsonism, fluctuating cognition, parasomnia, and hallucinations."
Two of the 6 patients have undergone autopsy; the pathologic diagnosis was FTLD-U.
The 6 patients were also compared to autopsy-confirmed groups of FTD and LBD patients. There were "significant differences between" the 6 patients and these other two groups, presumably in terms of clinical symptoms.
Cognitive & Behavioral Neurology. 2008 Sep;21(3):157-63.
Frontotemporal dementia mimicking dementia with Lewy bodies.
Claassen DO, Parisi JE, Giannini C, Boeve BF, Dickson DW, Josephs KA.
Department of Neurology, Mayo Clinic, Rochester, MN
BACKGROUND: Some patients with frontotemporal dementia (FTD) have concomitant extrapyramidal symptoms and psychosis and may simultaneously meet consensus criteria for FTD and for dementia with Lewy bodies (DLB). Clinicopathologic studies are helpful in understanding the underlying neurodegenerative process in such cases.
OBJECTIVE: To describe clinical and pathologic features of 6 patients with signs and symptoms suggestive of both a diagnosis of FTD and DLB at first clinical presentation, of which 2 patients have now undergone autopsy, and to compare them with autopsy-confirmed FTD and Lewy body disease patients.
RESULTS: All 6 patients met published consensus criteria for a diagnosis of both FTD and DLB (5 probable and 1 possible). Clinical symptoms of FTD included personality and behavioral changes, whereas those suggestive of DLB included Parkinsonism, fluctuating cognition, parasomnia, and hallucinations. Five patients underwent single photon emission computed tomography ((99m)Tc) imaging, which showed varying degrees of frontal lobe hypoperfusion. Magnetic resonance imaging, electroencephalogram, and electromyogram were not helpful in differentiating FTD from DLB. Histologic examination of the 2 autopsy cases was consistent with a pathologic diagnosis of TDP-43 proteinopathy; specifically frontotemporal lobar degeneration with ubiquitin-only immunoreactive changes, type 1. There were significant differences between these 6 patients and the 2 groups of autopsy confirmed FTD and Lewy body disease patients.
CONCLUSIONS: We have identified a novel group of FTD patients with clinical features that overlap with DLB, yet seem to be different from both typical FTD and typical Lewy body disease.
PubMed ID#: 18797258 (see pubmed.gov for abstract only)