Dementiaclassification

Irreversible Causes of
Dementia

Disease	Course of Illness	Clinical Features	Laboratory/ Radiographic Findings	Pathological Findings	Treatment
Alzheimer's Disease	Gradual onset commonly in 8th and 9th decade of life with stuttering but progressive course over 1-2 decades	Preserved long term memory, progressive loss of short term memory, sun-downing	Hippocampus, Temporal and parietal lobe atrophy	Neurofibrillary Tangles, Aluminum and amyloid deposits	acetylcholine esterase inhibotrs, NMDA recptor inhibitors with variable success to slow progression only
Parkinson's Disease	Gradual progression to dementia in <50% of cases	Tremor, masked facies, shuffling gait, hallucinations, somnelence, memory improves with cuing	Frontal lobe and substantia nigra atrophy	substantia nigra (dopamine producing cells) atrophy and cell death	dopamine receptor activators,dopamine replacement, transplants
Huntington's dementia	Progressive course over one decade starting in 4th to 6th decade of life. Strong herediatry component	choreform (dance-like) movements, insight preserving dementia that causes paranoia, anxiety, obsessive behavior and depression	Caudate nucleus atrophy, hereditary chromosomal aberation		neuroleptics such as reserpine in addition to antidepressants and anxiolytics for symptomatic control
Frontal lobe dementia (Pick's disease)		Dis-inhibition, speech abnormalities (ecolalia, logorrhea, ...)	Frontal lobe atrophy only
Multi-infarct (Binswanger's dementia)	Rapidly progressive often with a major stroke	Progressive memory loss in a patient with multiple cardiovascular risk factors	Lacunar infarcts in the deep white matter of the brain
Progressive supranuclear palsy

Reversible Causes of
Dementia

Diagnosis	Course	Clinical Features	Laboratory/Radi ographic findings	Pathology	Treatment
Alcohol Associated	Occurs after years of abuse	Confabulation, possible movement disorder	generalized atrophy	spinal cord disease	alcohol cessation, magnesium and vitamin B replacement
Depression	progresses to a plateau	self reported symptoms exceed findings on subjective testng	none	complex serotonin metabolism disregulation	antidepressants, St. John's wort, Tryptophan or 5HTP
Brain Mass	rapidly progressive	dementia as well as focal neurologic deficits	mass visualized on imaging studies	varies with diagnosis	surgical resection, radiation therapy
Liver Failure	Rapid and progressive to coma and death	circadian reversal, astrixis (tremor)	normal brain, liver cirrhosis, elevated serum ammonia	accumulated toxins depress nerve function	Treat underlying cause (hemorrhage, infection) that caused liver decompensation
Normal Pressure Hydrocephalus	Gradually progressive	Triad of Incontinence, ataxia (poor balance) and dementia	Large ventricles on CT scan	impaired reabsorption of CSF (brain fluid) causes excess accumulation	shuntng of fluid away from the brain to the peritoneum where it's reabsorbed