PATHOLOGICAL LESIONS IN SENILE DIABETES - POSSIBLE PATHOGENETIC INTERPRETATIONS

Pathohistological alterations of the kidney and pancreas were studied in a group of elderly diabetics divided into ''aged diabetics'' (AD) ( onset of diabetes before 60 years of age) and ''senile diabetics'' (SD ) (onset of diabetes after 70 years of age). The control groups were f ormed by middle-aged non-insulin dependent diabetics (NIDDM) and non-d iabetic elderly subjects. The non-diabetic elderly subjects showed no damage of pancreatic islets and the arterioles were also intact. The m iddle-aged NIDDM group having had diabetes for less than one year pres ented no alterations either. Middle-aged NIDDM patients affected by th e disease for longer than 10 years, displayed the characteristic diabe tic damage (hyalinization of the islets and arteriolar damage). in add ition, AD presented pancreatic lesions characteristic of long-term NID DM. SD were divided into two groups depending on the duration of disea se: shorter than 6 and longer than 10 years. The former presented smal l islets with few fibrotic cells and arteriolar damage, while the latt er presented a picture of transition between SD with duration of disea se shorter than 6 years and AD. The kidney in AD and SD affected by di abetes longer than 10 years resembled the kidney of NIDDM patients. SD with duration of disease shorter than 6 years had aspecific age-relat ed damage. These lesions seem to confirm that macroangiopathy represen ts the main pathogenesis of senile diabetes, being aggravated by the p ersisting hyperglycemia causing microangiopathy.