AN AUTOPSY STUDY OF THE ISLETS OF LANGERHANS IN ACUTE‐ONSET JUVENILE DIABETES MELLITUS

Abstract

The existence of lymphocytic inflammation of the islets of Langerhans—insulitis—in the early stages of juvenile diabetes mellitus (j.d.m.) has been a matter of discussion. In order to evaluate the possible occurrence of insulitis in early j.d.m. the present autopsy study was performed. From the years 1943 to 1974 blocks of pancreatic tissue were collected from 11 juvenile diabetics aged less than 30 years and dying within 2 months after the onset of diabetic symptoms. Pancreatic tissue blocks from 22 age‐and‐sex‐matched sudden, unexpected deaths served as control material. 5‐micron thick sections from the 33 blocks were stained with hematoxylin‐eosin, aldehyde‐fuchsin and silver. 1‐micron sections were stained with toluidine blue. Islets were found in all the control cases, and A‐ and B‐cell granulations were distinct. Insulitis was absent. Islets were also present in all the diabetic cases. No difference in islet number between the controls and the diabetics was apparent. The diabetic islets were morphologically heterogeneous. No difference beween controls and diabetics could be demonstrated in respect of A‐cell number and granulation. However, B‐cell granulation was demonstrable in only 1 case, and in that case in extremely reduced proportion. Insulitis was present to varying degrees in 6 of the diabetics. In this material, like others, insulitis seems most frequent in the diabetics aged less than 10 years. No conclusion can be drawn from this study about whether an infectious agent, an autoimmune process, or a combination of these, causes the insulitis. However, the findings presented suggest the existence of a lymphocytic insulitis as a feature of early j.d.m.