Conditions which can cause a reversible dementia:
(1) adverse drug reaction
(2) toxic reaction
(3) electrolyte disorder
(4) dehydration
(5) renal failure
(6) hepatic failure
(7) hypoxemia
(8) Wilson's disease (hepatolenticular degeneration)
(9) hyperlipidemia
(10) normal pressure hydrocephalus
(11) intracerebral tumor
(12) chronic subdural hematoma
(13) meningitis or brain abscess (chronic bacterial or fungal)
(14) tuberculosis
(15) parasitic infection (toxoplasmosis, cysticercosis)
(16) HIV disease
(17) Whipple's disease
(18) neurosyphilis
(19) neuroborelliosis (Lyme disease)
(20) autoimmune disease
(20a) SLE
(20b) rheumatoid arthritis
(20c) temporal (giant cell) arteritis
(20d) vasculitis
(21) sarcoidosis
(22) idiopathic hypereosinophilic syndrome
(23) hyper or hypothyroidism
(24) hyper or hypoparathyroidism
(25) adrenal disease (Cushing's or Addison's)
(26) pituitary disease (adenoma, panhypopituitarism)
(27) insulinoma (carcinoid tumor) or other cause of recurrent hypoglycemia
(28) vitamin B12 deficiency
(29) folate deficiency
(30) pellagra (niacin deficiency or inability to convert tryptophan to niacin)
(31) thiamine deficiency (beriberi, vitamin B1)
(32) chronic alcoholism
(33) depression (psychiatric pseudodementia)
(34) obstructive sleep apnea syndrome
(35) chronic obstructive pulmonary disease (COPD)
(36) congestive heart failure (CHF)
(37) limbic encephalitis (paraneoplastic syndrome)
(38) radiation-induced
(39) aluminum-related (dialysis) encephalopathy
(40) Binswanger type of vascular dementia
