beriberi

Beriberi is a disease caused by deficiency of thiamine (vitamin B1). Thiamine is an essential cofactor for enzymes in carbohydrate metabolism, and its shortage impairs energy production, especially in the nervous system and heart. It occurs worldwide in settings of inadequate intake, malabsorption, increased requirements, or loss, and is linked to diets based on polished rice or maize.

There are several forms. Dry beriberi is primarily a neurological condition with symmetrical peripheral neuropathy, numbness, weakness, and muscle wasting. Wet beriberi involves the cardiovascular system, causing rapid heart rate, edema, and heart failure. Infantile beriberi affects breastfed infants of deficient mothers and can present with poor feeding, irritability, vomiting, rapid breathing, edema, and failure to thrive. Severe deficiency can also cause cerebral beriberi, a serious brain-associated syndrome.

Risk factors include chronic alcohol use, malnutrition, gastrointestinal disorders that impair absorption, pregnancy, and after bariatric surgery. Diagnosis is clinical and supported by laboratory tests showing low thiamine levels or reduced erythrocyte transketolase activity; a rapid improvement after thiamine administration strongly supports the diagnosis.

Treatment consists of prompt thiamine replacement, typically starting with intravenous or intramuscular administration followed by oral supplementation. Thiamine should be given before glucose administration in suspected deficiency to prevent potential worsening of neurologic symptoms. Most patients improve with treatment, though recovery may be incomplete if deficiency is prolonged.

Prevention focuses on adequate dietary intake and, for at-risk groups, food fortification and targeted supplementation. Beriberi is now rare in many developed regions but remains a concern in areas with limited access to thiamine-rich foods or where malnutrition is prevalent.