IRON METABOLISM IN TROPICAL MEDICINE

Abstract

Many cases of sideropenic symptoms, other than hypochromic, microcytic anemia, have been collected in Kyushu and in Okinawa. They include sideropenic adynamia, flat-, spoon-and fragile nails, angular stomatitis, rhinitis atrophicans-ozaena, dysphagia, hypo-and anacidity, gastritis atrophicans, pica including olfactory pica, a retardation of physical and mental growth. Possible occurrence of congenital malformations has been proposed. Considering the roles of iron in the organism, other than hemoglobin, pathobiochemical observations have been done in clinical cases and experimental animals. Citrate accumulation in blood and tissues, low ATP synthesis, slow down of TCA-cycle, due to a decrease in ferrous enzyme activity (aconitase), might explain the mechanism of sideropenic adynamia. Low DNA synthesis, low cell renewal rate due to decreased activities in iron-flavin enzymes (NADH2-dehydrogenase and succinic acid dehydrogenase) would suggest the mechanism of disturbance in proliferation and maturation of cells in the epithelial tissues. In early childhood, iron deficiency could cause a retardation of growth, not only physical but mental, too. Iron deficiency in the embryos, might possibly cause congenital malformations, since flavin deficiency has been known to cause various malformations. Aetiological factors causing iron deficiency in Okinawa and in the tropics have been discussed. Less iron intake-iron poor pork, instead of beef, less iron absorption due to high calcium content in the tapwater, due to duodenojejunal lesions in strongyloidiasis and excess iron loss due to intestinal bleeding in ankylostomiasis, hematochyluria in filariasis etc. The dermal iron loss by excess sweating may be an additional factor in those, acclimatisation has not yet been established. For prophylaxis, following items have been recommended. Iron fortification of pork, removal of calcium from the tapwater, removal of parasites, iron premedication having to be done in some cases and cooking using old style iron pans, instead of stainless steel or alumite pans.