Amyloid deposition in Type II diabetes pancreas islets

A confocal micrograph showing amyloid deposition pancreatic islets from two different patients with Type II diabetes. The amyloid has been labelled with thioflavin S (green). Amyloid is deposited initially adjacent to capillaries but progressively replaces islet cells. The degree of amyloidosis is not related to the duration of disease. Patient (a) died aged 84 and had diabetes 12 years treated with sulphonylurea; 80% islets affected, and 80% islet mass has been replaced replaced by amyloid. Patient (b) died aged 65 years and had diabetes treated with sulphonylurea for 10 years; 1% islets affected, and 1% islet mass replaced.