Diabetes Mellitus Flashcards
Autoimmune disorder where the insulin-producing beta cells of the islets of Langerhans in the pancreas are destroyed by the immune system
This results in an absolute deficiency of insulin resulting in raised glucose levels
Patients tend to develop T1DM in childhood/early adult life and typically present unwell, possibly in diabetic ketoacidosis
Type 1 diabetes mellitus (T1DM)
This is the most common cause of diabetes in the developed world. It is caused by a relative deficiency of insulin due to an excess of adipose tissue. In simple terms there isn’t enough insulin to ‘go around’ all the excess fatty tissue, leading to blood glucose creeping up
Type 2 diabetes mellitus (T2DM)
This term is used for patients who don’t yet meet the criteria for a formal diagnosis of T2DM to be made but are likely to develop the condition over the next few years. They, therefore, require closer monitoring and lifestyle interventions such as weight loss
Prediabetes
Some pregnant develop raised glucose levels during pregnancy. This is important to detect as untreated it may lead to adverse outcomes for the mother and baby
Gestational diabetes
A group of inherited genetic disorders affecting the production of insulin. Results in younger patients developing symptoms similar to those with T2DM, i.e. asymptomatic hyperglycaemia with progression to more severe complications such as diabetic ketoacidosis
Maturity onset diabetes of the young (MODY)
The majority of patients with autoimmune-related diabetes present younger in life. There are however a small group of patients who develop such problems later in life. These patients are often misdiagnosed as having T2DM
Latent autoimmune diabetes of adults (LADA)
Any pathological process which damages the insulin-producing cells of the pancreas may cause diabetes to develop. Examples include chronic pancreatitis and haemochromatosis.
Drugs may also cause raised glucose levels. A common example is glucocorticoids which commonly result in raised blood glucose levels
Other types
- patients always require insulin to control the blood sugar levels. This is because there is an absolute deficiency of insulin with no pancreatic tissue left to stimulate with drugs
- different types of insulin are available according to their duration of action
Type 1 diabetes
- the majority of patients with type 2 diabetes are controlled using oral medication
- the first-line drug for the vast majority of patients is metformin
- second-line drugs include sulfonylureas, gliptins and pioglitazone.
- if oral medication is not controlling the blood glucose to a sufficient degree then insulin is used
Type 2 diabetes
Subcut. administration
Used in all patients with T1DM and some patients with poorly controlled T2DM
Can be classified according to source (analogue, human sequence and porcine) and duration of action (short, immediate, long-acting)
MOA: Direct replacement for endogenous insulin
Insulin
Main side effects:
- Hypoglycaemia
- Weight gain
- Lipodystrophy
PO
First-line medication in the management of T2DM
Cannot be used in patients with an eGFR of < 30 ml/min
MOA: Increases insulin sensitivity
Decreases hepatic gluconeogenesis
Metformin
Main side effects:
- Gastrointestinal upset
- Lactic acidosis
PO
Examples include gliclazide and glimepiride
MOA: Stimulate pancreatic beta cells to secrete insulin
Sulfonylureas
Main side effects:
- Hypoglycaemia
- Weight gain
- Hyponatraemia
PO
Only currently available thiazolidinedione is pioglitazone
MOA: Activate PPAR-gamma receptor in adipocytes to promote adipogenesis and fatty acid uptake
Thiazolidinediones
Main side effects:
- Weight gain
- Fluid retention
PO
MOA: Increases incretin levels which inhibit glucagon secretion
DPP-4 inhibitors (-gliptins)
Generally well tolerated but increased risk of pancreatitis
PO
Typically result in weight loss
MOA: Inhibits reabsorption of glucose in the kidney
SGLT-2 inhibitors (-gliflozins)
Main side effect: Urinary tract infection
