Folic acid deficiency tropical sprue

In tropical sprue, both in Hong Kong and in Puerto Rico, folic acid deficiency is a constant and early feature (B25, F18). Its importance in sprue was first demonstrated by Spies and his colleagues (S18) in the West Indies. However, it cannot be concluded that tropical sprue is simply due to dietary folic acid deficiency. In Hong Kong the condition may develop in a previously healthy individual on an adequate... 

ABSORPTION, DISTRIBUTION, AND ELIMINATION As with vitamin Bj, the diagnosis and management of folic acid deficiency depend on an understanding of the transport pathways and intracellular metabolism of the vitamin (Figure 53-10). Folates present in food are largely in the form of reduced polyglutamates, and absorption requires transport and the action of a pteroyl-glutamyl carboxypeptidase associated with mucosal cell membranes. The mucosae of the duodenum and upper part of the jejunum are rich in dihydrofolate reductase and can methylate most or aU of the reduced folate that is absorbed. Since most absorption occurs in the proximal small intestine, it is not unusual for folate deficiency to occur with jejunal disease. Both nontropical and tropical sprues are common causes of folate deficiency. 

Folic acid deficient humans develop a macrocytic hyperchromic anemia similar to that observed in vitamin Bi2 deficiency. Observations made on the undernourished population of Bombay prompted the discovery of the vitamin. In 1932, Will observed that macrocytic anemia occurred frequently among the people of Bombay and that the disease was readily cured by the addition of yeast to the diet. Folic acid deficiency also seems to be responsible for the macrocytic anemia that develops in cases of tropical sprue. 

Megaloblastic anem/a.- Treatment of megaloblastic anemias due to a deficiency of folic acid as seen in tropical or nontropical sprue, anemias of nutritional origin, pregnancy, infancy, or childhood. 

Tropical sprue, caused by a deficiency of folic acid and vitamin B-12. 

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