Definition
- A heterogeneous metabolic disorder characterized by the presence of hyperglycemia with carbohydrate, protein and fat metabolism disturbance which results from defects in either insulin secretion or action or both
- Various genetic and environmental factors can cause progressive loss of β-cell mass and/or function that manifests clinically as hyperglycemia in both type 1 and 2 diabetes mellitus
- When hyperglycemia occurs, patients with both type 1 and 2 diabetes mellitus are at risk of developing the same complications but with different rates of occurrence as well as progression
- Better characterization of the many paths to β-cell dysfunction is required in the identification of individualized therapies for diabetes
Signs and Symptoms
- Patients usually present with polyuria, polydipsia and unexplained weight loss
Type 1 Diabetes Mellitus
- Most patients present with ketoacidosis or acute onset of hyperglycemia
- Other patients have presentation similar to type 2 diabetes mellitus
- Patients may have late onset and slow disease progression
- Patients may also have other autoimmune disorders (eg Graves’ disease, Hashimoto’s thyroiditis, Addison’s disease)
Type 2 Diabetes Mellitus
- Majority of patients are asymptomatic
- Ketoacidosis is uncommon and usually secondary to stress (eg infection)
- Diagnosis may not be obvious until complications have appeared
- Hyperglycemia develops gradually and during early stage, symptoms are often not severe enough for the patient to recognize