ABSTRACT
Infantile beriberi occurs usually in an acute form in breast-fed infants of mothers who reveal signs of a Vitamin B-1 (thiamine) deficiency. Thiamin deficiency in alcoholics is generally due to a decreased intake of the vitamin, but may be aggravated by malabsorption, impaired utilization, or by increased metabolism and excretion. Urinary excretion of thiamin provides an indication of recent dietary intake of the vitamin but only a limited reflection of body stores of thiamin. Tissue stores of thiamin will be depleted with intakes of the vitamin below the critical point and, if continued, will result in symptoms of a deficiency. Measurement of erythrocyte thiamin pyrophosphate concentrations by high performance liquid chromatography has been useful for the evaluation of thiamin status. In the human, thiamin pyrophosphate catalyzes two general types of reactions: the formation of ketoses as catalyzed by transketolase and the oxidative decarboxylation of a-keto acids catalyzed by dehydrogenase complexes.
