Mast cells in the islets of Langerhans. A study of their behaviour in connection with diabetes and with insular amyloidosis.

The number of mast cells in the islets of Langerhans in 60 cases was determined in an autopsy study. The 60 patients were divided into 4 groups, distinguishing between those with diabetes, insular amyloidosis, those with both these pathological conditions and those with neither diabetes nor insular amyloidosis. As compared with the control group, it was discovered that there was a sharp increase in mast cells in the group with insular amyloidosis and in the group with diabetes; the number of mast cells tended to increase even more in the presence of both pathological conditions. With these data in hand, it is assumed that the increase in mast cells in the islets of Langerhans is not only due to the presence of amyloidosis, but that it is also brought about as a direct consequence of diabetes.