The clinical diagnosis and misdiagnosis of senile dementia of Lewy body type (SDLT).
BACKGROUND
Current clinical classifications do not contain specific diagnostic categories for patients with senile dementia of the Lewy body type (SDLT), recently proposed as the second commonest neuropathological cause of dementia in the elderly. This study determines how existing clinical diagnosis systems label SDLT patients and suggests how such patients may be identified.


METHODS
A range of clinical diagnostic criteria for dementia were applied to case notes of autopsy-confirmed SDLT (n = 20), dementia of Alzheimer type (DAT; n = 21) and multi-infarct dementia (MID; n = 9) patients who had received psychogeriatric assessment. The predictive validity of each set of clinical criteria was calculated against the external criterion of neuropathological diagnosis.


RESULTS
Many SDLT patients erroneously met criteria for MID (35% with Hachinski scores > or = 7) or for DAT (15% by NINCDS 'probable AD', 35% by DSM-III-R DAT and 50% by NINCDS 'possible AD'). Up to 85% of SDLT cases could be correctly identified using recently published specific criteria.


CONCLUSIONS
SDLT usually has a discernible clinical syndrome and existing clinical classifications may need revision to diagnose correctly such patients.
McKeith
I G
IG
MRC Neurochemical Pathology Unit, Brighton Clinic, Newcastle Mental Health (NHS) Trust.
Fairbairn
A F
AF
Perry
R H
RH
Thompson
P
P
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000145:classification / Q000175:diagnosis / Q000473:pathology; D001921:Brain / Q000473:pathology; D003704:Dementia / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D015161:Dementia, Multi-Infarct / Q000145:classification / Q000175:diagnosis / Q000473:pathology; D003951:Diagnostic Errors; D015577:Geriatric Assessment; D006801:Humans; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010300:Parkinson Disease / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011594:Psychometrics; D015203:Reproducibility of Results