Type 1 Diabetes Flashcards
Which countries have a particularly high prevalence of type 1 diabetes?
Kuwait and UAE
What is the UK prevalence of type 1 diabetes?
0.3-0.4%
When are most cases of T1DM diagnosed? When is there a secondary peak?
Most cases are diagnosed in adolescence, with a secondary peak in the late 30s
What is the simplest explanation of the cause of T1DM?
Environmental trigger in a genetically susceptible individual
T1DM is mediated by what kind of process? Where does this occur?
An autoimmune processes occurring within the pancreatic beta cells
Pancreatic beta cells are found where in the pancreas?
Islet’s of Langerhan’s
Where in the Islet are beta cells seen? What do they produce?
In the middle of the Islet, they produce insulin
Where in the Islet are alpha cells seen? What do they produce?
In the periphery of the Islet, they produce glucagon
What type of hypersensitivity reaction is T1DM? What mediates this?
Type IV- cell mediated (T cells)
In T1DM, the T cells attack where?
The pancreatic beta cells
What is the effect of a lack of insulin?
Glucose builds up in the blood because it cannot enter cells
T1DM occurs mainly because of a genetic abnormality involving what system?
HLA genes
The HLA system is made up of a group of genes on which chromosome? What is this group known as?
MHC group on chromosome 6
What is the MHC protein important for?
Helping the immune system to recognise foreign antigens, and for self-tolerance
HLA represents around 50% of the familial risk of T1DM. What are the highest risk genotypes?
HLA-DR3-DQ2 and HLA-DR4-DQ8
How likely is it that someone with T1DM will have one or both of the implicated HLA genes?
95% of those diagnosed < 30
If you have one of the HLA genes implicated in diabetes, does this mean you definitely have the condition?
No, many people will have this genotype without having diabetes
What are some environmental factors which may contribute to the development of T1DM?
Seasonality, timing of birth, viral infection, maternal factors, weight gain
There are many diagnoses of T1DM in which month?
January