Thiamine deficiency and errors of thiamine metabolism are believed to be the primary cause of<unk> . Thiamine, also called B1, helps to break down glucose. Specifically, it acts as an essential coenzyme to the TCA cycle and the pentose phosphate shunt. Thiamine is first metabolised to its more active form, thiamine diphosphate (TDP), before it is used. The body only has 2–3 weeks of thiamine reserves, which are readily exhausted without intake, or if depletion occurs rapidly, such as in chronic inflammatory states or in diabetes. Thiamine is involved in: # Metabolism of carbohydrates, releasing energy. # Production of neurotransmitters including glutamic acid and GABA. # Lipid metabolism, necessary for myelin production. # Amino acid modification. Probably linked to the production of taurine, of great cardiac importance. Neuropathology The primary neurological-related injury caused by thiamine deficiency in WE is three-fold: oxidative damage, mitochondrial injury leading to apoptosis, and directly stimulating a pro-apoptotic pathway. Thiamine deficiency affects both neurons and astrocytes, glial cells of the brain. Thiamine deficiency alters the glutamate uptake of astrocytes, through changes in the expression of astrocytic glutamate transporters EAAT1 and EAAT2, leading to excitotoxicity. Other changes include those to the GABA transporter subtype GAT-3, GFAP, glutamine synthetase, and the Aquaporin 4 channel. Focal lactic acidosis also causes secondary oedema, oxidative stress, inflammation and white matter damage. Pathological anatomy Cerebellum Despite its name, WE is not related to<unk> 's area, a region of the brain associated with speech and language interpretation. In most, early lesions completely reversed with immediate and adequate supplementation. Lesions are usually symmetrical in the periventricular region, diencephalon, the midbrain, hypothalamus, and cerebellar vermis. Brainstem lesions may include cranial nerve III, IV, VI and VIII nuclei, the medial thalamic nuclei, and the dorsal nucleus of the vagus nerve. Oedema may be found in the regions surrounding the third ventricle, and fourth ventricle, also appearing petechiae and small hemorrhages. Chronic cases can present the atrophy of the mammillary bodies. Endothelial proliferation, hyperplasia of capillaries, demyelination and neuronal loss can also occur. An altered blood–brain barrier may cause a perturbed response to certain drugs and foods.
Wernicke encephalopathy
Alcohol intoxication
Powassan encephalitis
Anti-Hu associated encephalitis
Glycine encephalopathy
Toxic encephalopathy
Early myoclonic encephalopathy
Ethylmalonic encephalopathy