1Vilniaus Miesto Klinikinė Ligoninė, Vilnius, Lithuania
Vitamin B1, also called thiamine, is one of the eight class B vitamins, responsible for facilitating conversion of major nutrients (carbohydrates, protein and fats) into energy. Due to inability of a human‘s organism to produce thiamine, it must be received with food – 0,33 mg to each 1000 kcal consumed. Vitamin B1 deficiency is considered when a recommended daily thiamine’s intake is not consumed. Alcohol abuse, diets poor in nutrients, recurrent vomiting as well as impaired thiamine absorption may all predispose vitamin B1 deficiency. Vitamin B1 is soluble in water and is stored in liver. Accumulation takes up to 18 days. It is converted into thiamine pyrophosphate during an active absorption process in duodenum. The absorption process depends on ATPase occurring in intestine and is hindered by alcohol intake. It is recommended that patients considered at risk have their thiamine levels measured more often. Patients with chronic alcoholism, HIV/AIDS, diabetes or people who are elderly or have undergone bariatric surgery, are all considered to be more susceptible to develop thiamine deficiency. Wernicke-Korsakoff syndrome (WKS) and beriberi disease are the two most commonly encountered complications caused by thiamine deficiency. It is very rare, however, for them both to occur simultaneously. WKS is usually caused by alcohol abuse and nutrition-lacking diets. It initially affects central nervous system. When untreated, Wernicke encephalopathy develops and may lead to Korsakoff syndrome. Treatment must be initiated immediately in order to prevent disease progression and potential irreversible brain damage. Thiamine deficiency may also cause beriberi disease, which, similarly to WKS, is usually linked to alcohol abuse, but may also be caused by other factors. There are two types of beriberi – wet and dry. Treatment of vitamin B1 deficiency depends on severity of experienced symptoms. Patients at higher risk groups are recommended to take thiamine supplements on a daily basis. In order to prevent lactic acidosis and thiamine deficiency in patients suffering from chronic alcoholism, it is recommended to prescribe thiamine-rich diets.
Keywords: thiamine, vitamin B1, Wernicke encephalopathy, Korsakoff syndrome, beriberi disease.