Type 1 diabetes Flashcards
What is type 1 diabetes?
autoimmune condition in which insulin-producing beta-cells in the pancreas are attacked and destroyed by the immune system
What is the result of type 1 diabetes?
a partial or complete deficiency of insulin production, which results in hyperglycaemia (life long insulin treatment)
What are the different types of diabetes?
- Type 1 Diabetes
- Type 2 Diabetes
- Hybrid forms
- Other
- Unclassified
- During pregnancy
What is latent autoimmune diabetes in adults (LADA)?
Autoimmune diabetes leading to insulin deficiency can present later in life
How can monogenic diabetes present?
phenotypically as Type 1 or Type 2 diabetes (eg. MODY, mitochondrial diabetes)
When can diabetes show?
- T2DM may present in childhood
- Diabetes may present following pancreatic damage or other endocrine disease
Can T1 be diagnosed later in life?
Yes
What are stages of development of T1 diabetes?
- Genetic predisposition
- Potential precipitating event - Overt immunological abnormalities; normal insulin release
- Progressive loss of insulin release; glucose normal
- Overt Diabets; C peptide present
- No C peptide present
- B cells reducing this whole time
Why is the immune basis of T1 important?
- Increased prevalence of other autoimmune disease
- Risk of autoimmunity in relatives
- More complete destruction of B-cells
- Auto antibodies can be useful clinically
- novel treatments
What is the first step in immune response?
presentation of auto-antigen to autoreactive CD4+ T lymphocytes
What cells do CD4+ cells activate?
CD8+ T lymphocytes
Where do CD8+ T lymphocytes travel to?
islets and lyse beta-cells expressing auto-antigen
Why is the attack of CD8+ T cells even worse?
- Exacerbated by release of pro-inflammatory cytokines
2. Underpinned also, by defects in regulatory T-cells that fail to supress autoimmunity
Are all beta cells in T1 destroyed?
No, some can produce small amounts of insulin but still need insulin therapy
What environmental factors are suggested in T1?
- Enteroviral infections
- Cow’s milk protein exposure
- Seasonal variation
- Changes in microbiota
When are pancreatic auto antibodies detectable?
in the sera of people with Type 1 diabetes at diagnosis
What are some pancreatic auto-antibodies?
- Insulin antibodies (IAA)
- Glutamic acid decarboxylase (GADA) – widespread neurotransmitter
- Insulinoma-associated-2 autoantibodies (IA-2A)-Zinc-transporter 8 (ZnT8)
Are pancreatic auto antibodies need for diagnosis?
Not generally
What are the symptoms for type 1 diabetes?
- Excessive urination (polyuria)
- Nocturia
- Excessive thirst (polydipsia)
- Blurring of vision
- Recurrent infections eg thrush
- Weight loss
- Fatigue
What the signs of type 1 diabetes?
- dehydration
- cachexia
- hyperventilation
- smell of ketones
- glycosuria
- ketonuria
What are the aims for T1 treatment?
- Maintain glucose levels without excessive hypoglycaemia
- Restore a close to physiological insulin profile
- Prevent acute metabolic decompensation
- Prevent microvascular and macrovascular complications
What are acute complications of hyperglycaemia?
Diabetic ketoacidosis
What are chronic microvascular complications of hyperglycaemia?
- Retinopathy
- Neuropathy
- Nephropathy
What are the chronic macrovascular complications of hyperglycaemia?
- Ischaemic heart disease
- Cerebrovascular disease
- Peripheral vascular disease
What is the management of type 1 diabetes?
- Insulin Treatment
- Dietary support / structured educations
- Technology
- Transplantation
What are the types of insulin With meals (short / quick-acting insulin)?
- Human insulin – exact molecular replicate of human insulin (actrapid)
- Insulin analogue (Lispro, Aspart, Glulisine)