Diabetes mellitus

Definition

• Disorder of glucose metabolism resulting in chronically elevated serum glucose levels

Causes and Classification

• Type 1: absolute insulin deficiency from beta-islet cell destruction
  • Type 1a: autoimmune beta-islet destruction
  • Type 1b: beta-islet destruction without known cause
  • Latent autoimmune diabetes in adults (LADA): insulin resistance that progresses to autoimmune diabetes and insulin dependency over several years
• Type 2: insulin resistance and varying degrees of insulin deficiency
• Genetic conditions
  • Maturity-onsent diabetes of the young (MODY): autosomal dominant condition that causes type 2 diabetes in those under 25
  • Wolfram syndrome: diabetes insipidus, diabetes mellitus, optic atrophy, and deafness (DIDMOAD)
• Exocrine pancreas disorders
  • Cystic fibrosis
  • Hereditary hemochromatosis
  • Chronic pancreatitis
  • Fibrocalculous pancreatic diabetes
• Drug-induced
  • Steroids
  • Many others
• Stiff-person syndrome
• Anti-insulin receptor antibodies