Beriberi

Beriberi refers to a cluster of symptoms caused primarily by a nutritional deficit in vitamin B1 (thiamine). Beriberi has conventionally been divided into three separate entities, relating to the body system mainly involved (peripheral nervous system or cardiovascular) or age of person (infantile). Beriberi is one of several thiamine-deficiency related conditions which may occur concurrently, including Wernicke's encephalopathy (mainly affecting the central nervous system), Korsakoff's syndrome (amnesia with additional psychiatric manifestations), and Wernicke-Korsakoff syndrome (with both neurologic and psychiatric symptoms).

Historically, beriberi has been common in regions dependent on what is variously referred to as polished, white, or dehusked rice. This type of rice has its husk removed to extend its shelf life, but also has the unintended side effect of removing the primary source of thiamine.

Signs and symptoms

Symptoms of beriberi include weight loss, emotional disturbances, impaired sensory perception, weakness and pain in the limbs, and periods of irregular heart rate. Edema (swelling of bodily tissues) is common. It may increase the amount of lactic acid and pyruvic acid within the blood. In advanced cases, the disease may cause high-output cardiac failure and death. Symptoms may occur concurrently with those of Wernicke's encephalopathy, a primarily neurological thiamine-deficiency related condition.