ABSTRACT
Thiamine deficiency (TD) is the underlying cause of Wernicke's encephalopathy (WE), an acute neurological disorder characterized by structural damage to key periventricular structures in the brain. Increasing evidence suggests these focal histological lesions may be representative of a gliopathy in which astrocyte-related changes are a major feature of the disorder. These changes include a loss of the glutamate transporters GLT-1 and GLAST concomitant with elevated interstitial glutamate levels, lowered brain pH associated with increased lactate production, decreased levels of GFAP, reduction in the levels of glutamine synthetase, swelling, alterations in levels of aquaporin-4, and disruption of the blood-brain barrier. This review focusses on how these manifestations contribute to the pathophysiology of TD and possibly WE.
Subject(s)
Astrocytes/physiology , Thiamine Deficiency/physiopathology , Amino Acid Transport System X-AG/physiology , Animals , Biological Transport , Blood-Brain Barrier , Brain/pathology , Disease Models, Animal , Excitatory Amino Acid Transporter 2/physiology , Glutamic Acid/metabolism , Humans , Ketoglutarate Dehydrogenase Complex/physiology , Nerve Tissue Proteins/physiology , Neurons/metabolism , Neurons/pathology , Oxidative Stress , Pyrithiamine/toxicity , Thiamine Deficiency/chemically induced , Thiamine Deficiency/metabolism , Wernicke Encephalopathy/etiology , Wernicke Encephalopathy/metabolism , Wernicke Encephalopathy/physiopathologyABSTRACT
Wernicke encephalopathy is caused by thiamine deficiency. Although the clinical picture has been well established for some time, clinical diagnosis is attained in only 20% of the cases. MR imaging techniques contribute to early diagnosis of Wernicke encephalopathy. We herein report MR imaging and proton MR spectroscopic findings for a patient with clinical and biochemical features consistent with Wernicke encephalopathy. Increased lactate and typical MR imaging findings are discussed in the context of the known pathophysiology of Wernicke encephalopathy.