Some Aspects of Ageing in Africans 109 



labial stomatitis, a stigma of persistent low-grade malnutri- 

 tion, so frequent in these cases, is also apparent in Fig. 4. 



Another clinical feature which we encountered, and which, 

 I have felt for many years, has been misdiagnosed in the 

 African, is the so-called "arcus senilis". Fig. 6 shows what in 

 the African I would call (and consider comparable with similar 

 ocular changes in Europeans) a "true" arcus senilis. However, 

 the limbic change shown in Fig. 7, and which is frequently, in 

 my opinion, misdiagnosed as arcus senilis, I do not consider 

 to be a "true" arcus senilis, but the brownish colour here is 

 probably a deposition of iron pigment in the limbic portion 

 of the cornea and associated with a marked pigmentation of 

 the exposed conjunctiva. The entire picture in the African 

 seems indistinguishable, clinically and histopathologically, 

 from what is generally regarded among European people as 

 haemochromatosis. We refer to this condition in the African 

 as "nutritional siderosis". 



The hepatic siderosis presents itself in several forms repre- 

 senting, we think, different stages in the progress of this 

 disease. Most of the slides that follow are coloured photo- 

 micrographs of sections from liver biopsy material stained to 

 demonstrate iron. Thus, Fig. 8 represents the appearance of 

 the mild form of hepatic siderosis. The iron, at this stage of 

 the disease, is encountered mainly in the liver cells them- 

 selves, usually confined to the biliary poles of the cells (Fig. 9), 

 with small amounts only in occasional phagocytes, either in 

 the sinusoids or in the portal tracts. This probably represents 

 a very early stage in this disease, and as stated elsewhere 

 (Gillman and Gillman, 1951), we believe the iron to arise 

 initially as a result of disturbances in the metabolism of 

 intracellular iron-containing enzymes. Hence the name 

 "cytosiderosis". 



In what probably represents a slightly more advanced 

 lesion the iron is now aggregated in clumps within the liver 

 cells and seems also to be accumulating rapidly, although 

 probably intermittently and in graded quantities, in the 

 Kupffer cells, or in clumps of phagocytes in the lobules as well 



