ULTRASTRUCTURE OF THE ISLETS OF LANGERHANS IN PROTEIN-ENERGY MALNUTRITION

Significant hormonal changes have been reported in childhood malnutrit ion, including high serum levels of growth hormone and cortisol, and l ow levels of circulating insulin. The ultrastructure of the endocrine pancreas in such patients has hitherto not been reported. A light micr oscopy survey of the pancreatic islets was carried out on 69 malnouris hed children dying from protein-energy malnutrition. In seven of these cases, a rapid autopsy protocol allowed tissues to be fixed for elect ron microscopy within 75 minutes of death. This paper presents the fir st ultrastructural observations on the Islets of Langerhans in childho od protein-energy malnutrition. In all cases, there was a variable deg ree of degeneration of all cell types with membrane damage, loss of ri bosomes, vesiculation and mitochondrial swelling. In addition, the B-c ells showed a high proportion of precursor granules compared to crysta l forms, possibly accounting for low insulin serum levels reported by other workers. It is suggested that islet cell changes may be related to free radical damage secondary to depletion of glutathione and other antioxidants, as well as relative deficiencies of cysteine and zinc. In addition, the effects of agonal anoxia, and a short fixation delay after death must be considered