General Discussion 189 



yet hepatic siderosis is still common. In Kenya and Uganda, how- 

 ever, severe anaemias are common (Foy, H., and Kondi, A. (1956). 

 Lancet, i, 423) but siderosis is absent. The excessive iron in the liver 

 and other tissues must, in the ultimate analysis, come from the diet. 

 But the mechanism promoting the prolonged absorption, from the 

 gut, of excessive iron is not known. As indicated already, during 

 the earlier stages of siderosis, the iron is almost entirely confined to 

 the hepatic epithelium, myocardial cells and other parenchymal cells, 

 and very little is present in the reticuloendothelial system. This 

 picture speaks against a haemolytic origin of the siderosis. In the 

 presence of chronic malnutrition the apparently large quantities of 

 iron reported to occur in the African's diet (Walker, A. R. P., and 

 Arvidsson, U. B. (1953). Trans, roy. Soc. trop. Med. Hyg.,47, 536) may 

 also play some role either in promoting or expediting this disease. 

 However, I do not think that a high iron intake alone, especially in a 

 "good" diet or well-nourished individual, can promote such extensive 

 and severe siderosis as we so frequently encounter. The experi- 

 mental work of Kinney and co-workers (Kinney, T. D., Kaufman, 

 N., and Klavins, J. (1949). J. exp. Med., 90, 137, 147) supports this 

 view. There is also experimental work indicating that the alimentary 

 mucosal block to iron absorption is normally influenced, indirectly 

 and in part, by the iron stores in the reticuloendothelial system as well 

 as, perhaps, by some function(s) of the pancreas (Gillman, J., and 

 Gillman, T. (1951). Perspectives in Human Malnutrition. New York: 

 Grune & Stratton, Inc.). Bearing in mind the large quantities of 

 iron in the connective tissues of our cases, there would seem to be 

 some other forces promoting excessive iron absorption and retention. 

 We suspect some nutritionally conditioned intracellular disorder as 

 the primary lesion coupled, perhaps, with a high iron intake in a 

 primarily maize diet and possibly, in addition, some associated (also 

 nutritionally caused) pancreatic dysfunction (Gillman and Gillman, 

 1951, loc. cit.; Kinney, T. D., Kaufman, N., and Klavins, J. (1955). 

 J. exp. Med., 102, 151). 



Bourne: Yes, but the accumulation of tissue iron in these people is 

 very similar to the accumulation of iron that takes place in cobalt 

 deficiency. 



Lorge: Has anyone made studies, medical or otherwise, of so-called 

 "underdeveloped areas" which were Westernized suddenly? Puerto 

 Rico, for instance, in less than 50 years, has extended its life expect- 

 ancy to almost that of continental United States. Now, did anyone 

 make collections of livers (or of any other organ) and did anyone 

 subsequently collect livers, after such a great improvement had taken 

 place in the nutritional status, to see whether there is any fundamental 

 difference ? 



