Diabetes mellitus

Diabetes mellitus (DM) is a group of disorders characterised by chronic hyperglycaemia due to abnormal carbohydrate metabolism. There are many types, but the most common types are type 1 diabetes mellitus and type 2 diabetes mellitus. DM is a very common disease, and the most common form, type 2, is associated with inactivity and obesity, which are increasing globally. Chronic hyperglycaemia causes severe long-term and short-term complications which may be lethal or cause significant morbidity.

There exists state of "prediabetes" where the carbohydrate metabolism is abnormal but not (yet) to such an extent that diabetes mellitus has manifested.

Types

• Type 1 diabetes mellitus
  • Type 1A (autoimmune) (almost all cases of T1D)
  • Type 1B (idiopathic) (autoantibodies absent; very rare)
  • Latent autoimmune diabetes in adults (LADA)
• Type 2 diabetes mellitus
• Other types of diabetes mellitus
  • Maturity onset diabetes of the young (MODY)
  • Pancreoprivic diabetes (diseases of exocrine pancreas)
    • Cystic fibrosis
    • Chronic pancreatitis
    • Hereditary haemochromatosis (bronze diabetes)
  • Endocrinopathies
    • Cushing syndrome
    • Acromegaly
  • Drug-induced diabetes
    • Glucocorticoids
    • Antipsychotics
    • +++
• Gestational diabetes

Diagnosis and evaluation

There are several ways to diagnose diabetes mellitus. If one fulfills any of the diagnostic criteria, they have DM.

Random plasma glucose

If one measures plasma glucose "randomly", i.e. without any preparation or fasting, and the result is > 11.1 mmol/L, they fulfill the diagnostic criterium of diabetes mellitus but only if they also have symptoms of diabetes mellitus. A random plasma glucose of 11.1 or higher in the absence of DM symptoms does not fulfill the criterium