Beriberi

Alternative names:

thiamine deficiency; vitamin B1 deficiency

Definition:

A vitamin deficiency disease, caused by a lack of vitamin B1 (thiamine); the most significant manifestations are damage to the heart and nervous system. It is the third most common cause of dementia in the US.

Causes, incidence, and risk factors:

Beriberi has become almost nonexistent in the United States since the discovery of its cause, thiamine deficiency. Most foods are vitamin enriched and a normal diet contains adequate amounts of thiamine.

Beriberi can appear, however, in breast-fed infants when the mother has an inadequate intake of thiamine or among people whose diet includes certain types of fish that produce an enzyme which inactivates thiamine.

Early symptoms of beriberi are nonspecific and include fatigue, irritability, restlessness, loss of appetite, and vague abdominal discomfort.

As the disease progresses, patients develop burning sensations, tingling in the extremities, and changes in sensation such as numbness. Patients may develop psychosis. Heart manifestations are caused by degeneration of the heart muscle and include heart failure with shortness of breath (dyspnea) and cyanosis (bluish tinged skin). Neurologic symptoms are caused by degeneration of the nerve fiber and its insulation (myelin). Death is generally a result of heart failure.

There are two kinds of beriberi: "dry" and "wet". Dry beriberi is associated with energy deprivation and inactivity characterized by mental confusion, peripheral neuropathy, muscular wasting with loss of function or paralysis of the lower extremities. Wet beriberi is resultant of high carbohydrate intake along with strenuous exercise characterized by edema, tachycardia, pulmonary congestion, and enlarged heart.

Updated Date: 02/09/00

Updated By:J. Gordon Lambert, MD, Associate Medical Director, Utah Health Informatics and adam.com editorial