Uncommon causes of diabetes are described by the American Diabetes Association (2010) in summary as follows:
Monogenetic defects in beta cell function are characterised by onset at an early age and impaired insulin secretion with minimal or no defects in insulin action. They include different subtypes of gene disorders including neonatal diabetes mellitus, monogenic diabetes of infancy, maturity-onset diabetes of the young (MODY) and other rarer diabetes-associated syndromic diseases.
Disease of the exocrine pancreas: Any process that injures the pancreas may cause diabetes including pancreatitis, pancreatectomy, pancreatic carcinoma, trauma and infection. Cystic fibrosis and haemochromatosis damage beta cells and impair insulin secretion.
Endocrinopathies: Several hormones antagonise insulin action; therefore an excess of these hormones may induce diabetes. Somatostatinoma and aldosteronoma-induced hypokalaemia can cause diabetes in part by inhibiting insulin secretion, but may resolve after removal of the tumour.
