All are reversible causes of dementia except ?

Ans. is 'd' i.e., Alzhimer's disease Reversible causes of dementia 1) Surgically treatable :- Normal pressure hydrocephalus, brain tumors (frontal lobe tumor), meningioma, subdural hematoma due to head injury, hydrocephalus. 2) Medically treatable :- Depression, hypothyroidism, alcohol abuse, vitamin B n/folate/Niacin deficiency, any metabolic or endocrine disturbance, neurosyphilis, Hashimoto's encephalopathy, Wilson's disease, celiac disease, whipple's disease, chronic meningoencephalitis, drugs and toxin (toxic dementia). Irreversible causes of dementia :- Alzheimer's disease, vascular (multi-infarct) dementia, Parkinsonism, Huntington's chorea, Lewy body dementia, Pick's disease.