View unanswered posts | View active topics It is currently Thu Apr 24, 2014 10:13 am



Reply to topic  [ 8 posts ] 
 PDD - "A diminished role for the Lewy body" 
Author Message

Joined: Fri Aug 11, 2006 1:46 pm
Posts: 4811
Location: SF Bay Area (Northern CA)
Post PDD - "A diminished role for the Lewy body"
Perhaps only a few of you are interested in this abstract. PDD (Parkinson's Disease Dementia) is a clinical diagnosis, not a pathological one. I would have assumed that those with a clinical diagnosis of PDD, would have DLBD or some other form of Lewy Body Disease upon post-mortem brain tissue analysis. According to this small study (done in NY) of 16 with a clinical diagnosis of PDD, surprisingly (to me), not every brain showed evidence of Lewy bodies.

This is just more fuel for the fire as to the discussion of the difference between Dementia with Lewy Bodies and Parkinson's Disease Dementia. While they clinically may be on the same spectrum, perhaps pathologically they are not.

Or, perhaps what this research means is that when MDs diagnose someone as having PDD, they aren't accurate in their diagnosis because the patients quite often end up having AD or VaD.

Robin


Parkinsonism & Related Disorders. 2009 Apr 3. [Epub ahead of print]

Parkinson's disease dementia - A diminished role for the Lewy body.

Libow LS, Frisina PG, Haroutunian V, Perl DP, Purohit DP.
The Jewish Home & Hospital LifeCare System, New York, NY 10025, USA; Department of Geriatrics and Adult Development, Mount Sinai School of Medicine, New York, NY 10029, USA; Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA.

The literature currently views Lewy bodies as central in the pathogenesis of Parkinson's disease dementia (PDD) when Alzheimer's disease (AD) or vascular pathology is not present. Because the neuropathology of PDD is not well understood, the pathological features of PDD were characterized in eighteen PD brain specimens using published criteria for AD, Diffuse Lewy Body Disease (DLBD), and Vascular Disease as a framework.

Among the PD dementia (n=16) subjects, 3 (19%) did not have LBs outside of the brain stem, nor AD or vascular pathology.

In two additional cases, one did have rare LBs in the neocortex and cingulate gyrus. However, these two cases did not meet the diagnostic criteria for DLBD.

Beyond these 5 cases, the remaining PD dementia subjects fitted a classical pathological profile consistent with AD (38%), vascular disease (12.5%), DLBD (6%), or a combination of these pathologies (12.5%). The findings from this study do not support the hypothesis that LBs are the main substrate for dementia in PD. More research with a larger sample size is needed to determine whether the LB may be a secondary phenomenon and/or an "innocent-bystander". The entire role of the LB in PD dementia is again brought into question.

PubMed ID#: 19346154 (see pubmed.gov for abstract only)


Tue Apr 07, 2009 7:40 pm
Profile

Joined: Thu May 14, 2009 7:26 pm
Posts: 1
Location: Suffern, New York
Post Alzheimer changes in Parkinson's disease
I haven't seen the full text yet, but I'm pretty sure that the authors didn't mean there were no Lewy bodies anywhere in the brain. The Lewy bodies were probably confined to the substantia nigra in the mid-brain and were absent in the cerebral cortex. Both the sunstantia nigra and the cerebral cortex are parts of the brain.
Alzheimer changes are very common the brains of the elderly There are probably some in my 74 year old brain. Sorting out the relationships between the quantity of Alzheimer brain changes, the degree of dementia, and the amount and location of Lewy bodies, involves a lot of fancy statistics, as well as neuropathology. You are dealing with three continuous variables and trying to define categorical entities.
D Peter Birkett

_________________
D Peter Birkett MD


Thu May 14, 2009 10:57 pm
Profile

Joined: Sat Oct 06, 2007 4:28 pm
Posts: 699
Location: LA
Post What it is with Mr B
Robin, this is one of the things I would talk with you about if we met face to face. The lack of parkinsonisms with Mr B. The rigidity comes and goes when he tries to do or not do certain things, the only time he has displayed tremors was after he had the haldol and was over-medicated with a variety of other drugs [all supposed to be safe for LBD] but they left him in a stupor.
He does not choke nor does he experience incontinence. I have repeated many times on this forum the problems he does have but the ones listed above are the ones we have been spared [so far]. For that reason, I wonder just what is in his brain.

DrP


Thu May 14, 2009 11:19 pm
Profile

Joined: Sat Jan 27, 2007 8:38 pm
Posts: 712
Location: CA
Post 
Dorthea --
Ditto with Jerome. No Parkinsonisms, no choking or incontinence, no rigidity. Wonder why this is ...
Renata

_________________
Renata (and Jerome-in-Heaven)


Thu May 14, 2009 11:44 pm
Profile

Joined: Fri Aug 11, 2006 1:46 pm
Posts: 4811
Location: SF Bay Area (Northern CA)
Post 
DrP,

As you may know, parkinsonism is NOT a required symptom for DLB to be diagnosed. Nor are swallowing problems or autonomic problems (eg, urinary incontinence). Do you consider Mr B lucky or not in this regard?

I remember participating in a PD conference call several years ago, put on by the Canadian Parkinson's Society. The MD said that, in PD, if you have more severe tremor and rigidity, then you are less likely to get psychosis and dementia, but if you had very mild tremor and rigidity, the more likely you were to get psychosis and dementia. I don't know what this means for DLB and PDD but perhaps the same is generally true.

Robin


Fri May 15, 2009 12:42 am
Profile

Joined: Fri Aug 11, 2006 1:46 pm
Posts: 4811
Location: SF Bay Area (Northern CA)
Post 
Hi Dr. Birkett,
Welcome to the Forum! What sort of MD are you? I hope you can get the full article and help us understand the significance of the findings (if any!). We value any education you can throw our way!
Robin


Fri May 15, 2009 12:44 am
Profile

Joined: Sat Oct 06, 2007 4:28 pm
Posts: 699
Location: LA
Post Lesser of two [many] evils
Robin, we can't pick and choose but since you asked if I thought Mr B. lucky in the symptoms he has rather than others, I would say, yes. I'm not sure how he would be with the blindness without his hallucinations and delusions. He sees nice people and regular fellows he can "boss" around. Without the Seroquel, Melatonin, Exelon, Namenda, and Gabapentin I would be tearing my hair out by the roots but I do a balancing act with those meds and when he gets terrified, I can give a booster dose until he returns to his happy though unreal companions. More physical problems would require others caring for him and I would miss out on the rare lucid moments we spend together. He does include me in his other world which can be a pleasure in itself.

DrP


Fri May 15, 2009 1:18 am
Profile

Joined: Sat Oct 06, 2007 4:28 pm
Posts: 699
Location: LA
Post The Big Picture
MM, I think the big picture will emerge with the final chapter of Post Mortem brain donations. This generation is furnishing the donations and asking the medical teams who provide care to send in their reports while our on site stories are here to complete the research. The scientists will have lots of information to match the symptoms with results for final analysis. They will be able to make a match so in the future perhaps it will not be so much guess work.

Everyone please keep writing, telling all, and making arrangements for the last chapter. Our stories are important.

dorthea


Fri May 15, 2009 5:04 pm
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 8 posts ] 

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by STSoftware for PTF.
Localized by MaĆ«l Soucaze © 2010 phpBB.fr