Week 3 readings summary Flashcards
what does diabetes mellitus (diabetes) refer to?
a condition in which blood glucose concentrations are elevated above normal
what are both types of DM characterised by?
development of long term complications
- damage to blood vessels and nerves
- Microvascular complications reduced by strict control of blood glucose
- Evidence that strict control of blood glucose less strong for macrovascular complications (atherosclerosis)
characteristics of DM
intensive thirst
frequent urination
what is diabetes insipidus?
Very rare
Characterized by thirst and urination but urine is watery (insipid), not sweet
Caused by failure of antidiuretic hormone (ADH) due to lack of it or a defect in receptors for ADH on kidney
what is gestational DM?
Diabetes that occurs during pregnancy
Those who develop this are as great risk of developing T2DM later in life
what is MODY? (Maturity onset diabetes of the young)
Group of conditions which are inherited in a mendelian fashion (MODY1)
Maturation in glucokinase affecting insulin secretion when B cells in pancreas sense increase in glucose conc (MODY2)
Other forms of MODY caused by mutations in transcription factors
what is LADA?
Underlying autoimmune process that ultimately damages pancreatic B cells, initially diagnosed as T2DM
Often move relatively early onto insulin treatment
cause of T1DM
autoimmune destruction of pancreatic B-cells in islet of Langerhans, abolishing insulin secretion
To some extent it is inherited, but also influence of the environment. - number of theories suggesting a viral infection, early exposure to cows milk or a traumatic episode can trigger diabetes
how to treat T1Dm
replacing insulin
what is diabetic ketoacidosis?
Too little insulin and blood glucose conc rises - blood becomes acidic because of the presence of ketone bodies and non-esterified fatty acids due to the breakdown of stored fuels caused by the metabolic disturbances of diabetes. Related to type 1.
how prevalent is type 1?
only present in 0.5% of population
cause of type2DM
combination of insulin resistance (insulin failing to act normally on its target tissues) an pancreatic B-cell failure
treatment of T2Dm
Do not usually need insulin for treatment in the early stages because pancreatic insulin secretion remains
Those who lose weight (especially early in the disease) the diabetes may revert almost to normal
Surgical treatment of obesity (gastric banding or bypass) may revert T2DM
drugs used to treat T2Dm
Sulfonylureas - acts directly on B cells in pancreas to promote insulin release
Biguanide drug - improves sensitivity of tissues to insulin, to reduce insulin resistance
Glitazones - improves sensitivity to insulin in all tissues e.g. muscle and liver
how to prevent diabetes
Children at risk of T1 may be identified by presence in blood of specific antibodies directed against targets in pancreatic islets
Drugs for T2 and modification of lifestyle e.g. diet (reducing saturated fat intake and increasing fibre) and increasing exercise
