What is Monogenic Diabetes?

Monogenic diabetes is the diabetes caused by a defective gene associated with the differentiation of pancreatic beta cells or the insulin gene. It usually occurs before the age of 25, in the late childhood and is called Maturity-onset diabetes of the youth or MODY in short. However, it can also occur in new-borns under 6 months of age. In this case it is called Neonatal Diabetes. On the other hand, mutations in the insulin receptor cause diabetes with insulin resistance as the main feature, of different severity. These mutations give rise to familial forms of insulin resistance. Patients can develop diabetes, polycystic ovarian syndrome and elevated androgens in the blood. In addition to the above genetic disorders, over 50 different genetic syndromes are associated with an increased likelihood of developing diabetes mellitus, such as Down, Turner and Prader-Willi syndromes.

What is Secondary Diabetes?

Secondary diabetes is the diabetes that occurs as a result of a disease unrelated to the pancreatic beta cells or insulin sufficiency. These are diseases of the pancreas, such as pancreatitis and pancreatic injury, cystic fibrosis and neoplasms. Also, endocrinopathies such as acromegaly, Cushing’s syndrome, pheochromocytoma and hyperthyroidism can lead to secondary diabetes. Furthermore, drugs and toxic substances, such as the new anti-cancer drugs, monoclonal antibodies against immune system proteins, anti-infective drugs, antipsychotic drugs, anti-hypertensive and immunosuppressive drugs are associated with secondary diabetes. However, the most common toxic substance causing diabetes is ethanol. Indeed, alcohol abuse can lead to chronic alcoholic pancreatitis and diabetes. Finally, some viruses can cause diabetes, such as congenital rubella and cytomegalovirus.