Type 1 Diabetes Flashcards
What type of condition is T1 diabetes? What happens?
An autoimmune condition in which insulin-producing beta-cells in the pancreas are attacked and destroyed by the immune system
What cells are involved with T1 diabetes?
Insulin-producing beta-cells in the pancreas
What happens to insulin levels and glucose levels in T1 diabetes?
The result is a partial or complete deficiency of insulin production, which results in hyperglycaemia that requires life long insulin treatment
What are treatment options for T1 diabetes?
Multiple daily insulin injections
Insulin pump
Islet cell transplant
Artificial pancreas (pump + real-time glucose monitoring)
At what ages does T1 diabetes present?
Usually in childhood but can be later
At what ages does T2 diabetes present?
Usually in adulthood but can be in children
Is diabetic ketoacidosis a feature of T1 or T2 diabetes?
Mainly T1 but can present in T2
How does T1 diabetes develop?
In stages:
Starts w genetic predisposition
Precipitating event (eg virus)
Autoimmune events are triggered
What is long standing T1 diabetes?
Immune cells are not near the islets and you are left with peri islet fibrosis
Describe the immunology of T1 diabetes
Primary step is the presentation of auto-antigen to auto-reactive CD4+ T lymphocytes
CD4+ cells activate CD8+ T lymphocytes
CD8+ cells travel to islets and lyse beta-cells expressing auto-antigen
Exacerbated by release of pro-inflammatory cytokines
Underpinned also, by defects in regulatory T-cells that fail to suppress autoimmunity
Are all beta cells destroyed in T1 diabetes?
No, a small amount of insulin may still be produced
Why is it useful to produce a small amount of insulin in T1 diabetes?
Less risk of complications occouring
What genes increase susceptibility of developing T1 diabetes most?
HLA genes
What are some environmental factors that can trigger T1 diabetes
There are loads but some include: Enteroviral infections Cow’s milk protein exposure Seasonal variation Changes in microbiota
What antibodies are present in T1 diabetes?
Pancreatic auto-antibodies
What are symptoms of T1 diabetes?
Excessive urination (polyuria) Nocturia Excessive thirst (polydipsia) Blurring of vision Recurrent infections eg thrush Weight loss Fatigue
What are signs of T1 diabetes?
dehydration cachexia (ongoing muscle wastage that can't be reversed by nutritional supplements) hyperventilation smell of ketones glycosuria ketonuria
What does lack of insulin do in muscles?
Increase proteinolysis
What does lack of insulin do in the liver?
Inhibit hepatic glucose output
Increase output of ketone bodies
What does lack of insulin do in adipose tissue?
Increase lipolysis
What are the aims for treatment in T1 diabetes?
Maintain glucose levels without excessive hypoglycaemia
Restore a close to physiological insulin profile
Prevent acute metabolic decompensation
Prevent microvascular and macro vascular complications
What are the main acute complication of T1 diabetes?
Diabetic ketoacidosis
Uncontrolled hyperglycaemia
Hypoglycaemia
Is human insulin ever zero?
No, we have a basal insulin level (it is relatively flat)
What are the 2 types of insulin given to diabetics?
Short acting insulin
Basal (long lasting) insulin
What is insulin pump therapy?
Continuous delivery of short-acting insulin analogue e.g. novorapid via pump into subcutaneous space
What do you have to do with an insulin pump?
Actively bolus for meals
What dietary advice are T1 diabetics given?
They should receive training for carbohydrate counting
Swap refined carbs for complex carbs
How does a closed loop/artificial pancreas work?
Have a real time glucose sensor that detects changes in glucose
Use an algorithm to calculate insulin requirement
Insulin pump delivers calculates insulin
What are choices for transplantation?
Islet cell transplant
Whole pancreas and kidney transplant
What do we need to transplant with the pancreas? When is pancreas transplant given
Transplant kidneys too
For those with end stage renal failure
What does transplantation require life long?
Immunosupression
What is the best blood test to monitor diabetes control?
Hba1c (glycated haemoglobin)
How are glucose levels mainly monitored?
Capillary (finger prick) blood glucose monitoring
What does Hba1c show? Give one disadvantage of it
Reflect last 3 months (red blood cell lifespan) of glycaemia
Biased to the 30 days preceding measurement
What is used to guide insulin dose?
Self monitoring and hba1c
How urgent is diabetic ketoacidosis?
Extremely, its a medical emergency
How is diabetic ketoacidosis diagnosed?
pH <7.3
Ketones increased (urine of capillary blood)
HCO3- <15 mmol/L
Glucose >11 mmol/L
How is hypoglycaemia diagnosed?
<3.6 mmol/L
What are symptoms of hypoglycaemia?
Adrenergic- tremor, palpitation, sweating, hunger
Neuroglycopaenic- somnolence, confusion, in cooridination, seizures/coma
When does hypoglycaemia become problematic?
Excessive frequency
Impaired awareness (unable to detect low blood glucose)
Nocturnal hypoglycaemia
Recurrent severe hypoglycaemia
What are risks of hypoglycaemia?
Seizure / coma/ death (dead in bed) Impacts on emotional well-being Impacts on driving Impacts on day to day function Impacts on cognition
What are risk factors for developing hypoglycaemia?
Exercise Missed meals Inappropriate insulin regime Alcohol intake- can blunt symptoms Lower HbA1c Lack of training around dose-adjustment for meals
How can we help those with hypoglycaemia?
Indication for insulin-pump therapy (CSII)
May try different insulin analogues
Revisit carbohydrate counting / structured education
Behavioral psychology support
Transplantation
