Thiamine deficiency

Thiamine deficiency[1]
Other names	Beriberi, vitamin B1 deficiency, thiamine-deficiency syndrome[1][2]
A man from Batangas riddled with beriberi contracted in a U.S. Army concentration camp, circa 1902
Specialty	Neurology, cardiology, pediatrics
Symptoms	Wet: Fast heart rate, shortness of breath, leg swelling[1] Dry: Numbness, confusion, trouble moving the legs, pain[1]
Types	Wet, dry, gastrointestinal,[3] infantile,[4] cerebral[5]
Causes	Not enough thiamine[1]
Risk factors	Diet of mostly white rice; alcoholism, dialysis, chronic diarrhea, diuretics[1][6]
Prevention	Food fortification, Food diversification[1]
Treatment	Thiamine supplementation[1]
Frequency	Uncommon (USA)[1]

Thiamine deficiency is a medical condition of low levels of thiamine (vitamin B₁).^[1] A severe and chronic form is known as beriberi.^[1][7] The name beriberi was possibly borrowed in the 18th century from the Sinhalese phrase බැරි බැරි (bæri bæri, “I cannot, I cannot”), owing to the weakness caused by the condition. The two main types in adults are wet beriberi and dry beriberi.^[1] Wet beriberi affects the cardiovascular system, resulting in a fast heart rate, shortness of breath, and leg swelling.^[1] Dry beriberi affects the nervous system, resulting in numbness of the hands and feet, confusion, trouble moving the legs, and pain.^[1] A form with loss of appetite and constipation may also occur.^[3] Another type, acute beriberi, found mostly in babies, presents with loss of appetite, vomiting, lactic acidosis, changes in heart rate, and enlargement of the heart.^[8]

Risk factors include a diet of mostly white rice, alcoholism, dialysis, chronic diarrhea, and taking high doses of diuretics.^[1][6] In rare cases, it may be due to a genetic condition that results in difficulties absorbing thiamine found in food.^[1] Wernicke encephalopathy and Korsakoff syndrome are forms of dry beriberi.^[6] Diagnosis is based on symptoms, low levels of thiamine in the urine, high blood lactate, and improvement with thiamine supplementation.^[9]

Treatment is by thiamine supplementation, either by mouth or by injection.^[1] With treatment, symptoms generally resolve in a few weeks.^[9] The disease may be prevented at the population level through the fortification of food.^[1]

Thiamine deficiency is rare in the United States.^[10] It remains relatively common in sub-Saharan Africa.^[2] Outbreaks have been seen in refugee camps.^[6] Thiamine deficiency has been described for thousands of years in Asia, and became more common in the late 1800s with the increased processing of rice.^[11]