L16 - Type 1 diabetes mellitus Flashcards
Peak onset of type 1 diabetes mellitus
- Peak onset at adolescence
Which antigens are associated with type 1 diabetes
- Association with HLA antigens:
* HLA DR3-DQ2 and DR4-DQ8 predispose
T1DM - Pathophysiology
- Beta-cell events trigger autoimmune response
- Antibodies to insulin or GAD generally appear first
- Other beta-cell antibodies follow - IA2, Zn2+ trasporter 8
- Selective immune beta-cell destruction
Autoimmune triggers in type 1 diabetes
- Viral infection (coxsackie)
- ER stress
- Cytokines
Diseases associated with type 1 diabetes
- Coeliac disease
- Hypothyroidism
- Grave’s disease
- Addison’s disease
- Hypogonadism
- Pernicious anaemia
- Vitiligo
- Autoimmune polyglandular syndromes
Symptoms of type 1 diabetes
- Lethargy
- Polyuria
- Polydipsia
- Blurred Vision
- Candida infections
- Weight Loss
- Ketosis/ Ketoacidosis
- Death
Diagnosing factors for type 1 diabetes
- Age of onset
- Rapidity of onset
- Phenotype
- PMH
- FH
- Weight loss
- Ketosis
- GAD/IA2/Zinc transporter 8 antibody positive
- C-Peptide
Insulin:C-peptide production ratio
- C-peptide is produced in 1:1 molar ratio with insulin
- Need adequate stimulus for secretion
How is insulin administered
Peptide hormone needs to be given parenterally
- Subcutaneously
- Inhaled
- Mucous membranes
Types of insulin
- Primary structure (animal, human, analogue)
- Duration of action (addition of protamine, altered solubility, fatty acid chain)
- Strength (100, 200, 300, 500 units/ml)
Injection sites for insulin
- Upper outer arms
- Lower abdomen
- Upper outer thighs
- Buttocks
Typical insulin regimen
- Basal bolus regimen
- Rapid acting insulin pre-meal (bolus)
- Long acting background insulin (basal)
- Balanced regimen
- Rapid acting insulin reflects CHO intake
Factors affecting blood glucose levels
- Diet
- Injection site
- Temperature
- Exercise
- Illness
- Stress
- Alcohol
- Menstrual cycle
How might a patient with hypoglycaemia present
- Autonomic symptoms
- Palpitation, sweating, tremor
- Neuroglycopaenic symptoms
- confusion
- Mild and severe
- Mild hypoglycaemia inevitable with good control
- Loss of warning signs
What is an insulin pump
An insulin pump is a small electronic device
The device is attached to your body via a thin tube called an Infusion Set, through which insulin is delivered. This makes insulin pump therapy very discreet. An insulin pump replaces the need for frequent injections by delivering rapid acting insulin continuously 24 hours a day.
What does basal rate mean (insulin pump)
This is the small amount of insulin that your insulin pump continuously gives you. Your pre-programmed rate is determined by your own body’s needs and programmed by your healthcare professional. Because the quantity can be more precise and the rates can be customised e.g. can very each hour if need be, an insulin pump can mimic a healthy pancreas more closely.
What does bolus rate mean (insulin pump)
Additional insulin can be delivered “on demand” to match the food you are going to eat or to correct a high blood sugar. Insulin pumps have bolus calculators that help you calculate your bolus amount based on settings that are pre-determined by your healthcare professional and again based on your individual needs.
Features of pancreas transplantation
- Almost always SPK or PAK
- Islet cell
- Edmonton protocol
- UK islet cell programme
How often should diabetics monitor their glucose levels
- Minimum 4 x daily
- Driving
- Unwell
- Hypoglycaemia
What else needs to be monitored in diabetic patients
- Ketone monitoring (blood and urine)
What is CGMS
A continuous glucose monitor is a small device that you wear just under your skin. It measures your glucose (sugar) levels continuously throughout the day and night, letting you see trends in your levels and alerts you to highs and lows.
What does CGM measure specifically
A CGM doesn’t actually measure your blood glucose levels, it measures the amount of glucose in the fluid that surrounds your body cells – called interstitial fluid.
There is a small time delay when checking this fluid, especially after eating or if you’re exercising. So your CGM result isn’t always exactly the same as your finger-prick result
Why does it help to check HbA1c (glycated haemoglobin) levels
- Reflects glucose over last 3 months
- Weight towards last 6 weeks
- Affected by red cell lifespan
