Diabetes Flashcards
How is T2DM diagnosed (3 ways)
HbA1c > 6.5% (48mmol/mol) (39-46mmol/mol = pre-diabetes) OR Random blood glucose >11.1 in presence of symptoms OR Random blood glucose >11.1 on two occasions with no symptoms
What factors can affect HbA1c, and make it invalid as a diagnostic tool?
- Conditions with increased red cell turnover eg. acute blood loss, pernicious anaemia, haemolytic anaemia, malaria, haemoglobinopathies - Pregnancy - Liver and renal disease - Ethnic variations
Describe the pathophysiology behind Type 1 diabetes
Insulin deficiency due to autoimmune attack of beta cells in the pancreas Linked to HLA D3/4
Describe the pathophysiology behind Type 2 diabetes
Acquired insulin resistance due to the body being unable to meet the requirement for insulin.
What conditions can cause secondary diabetes?
- Acromegaly - Cushing’s syndrome - Haemochromatosis - Pancreatitis
Describe the pathophysiology behind gestational diabetes
Excessive production of counter-insulin hormones (cortisol,oestrogen), produced during pregnancy, leading to a state of insulin resistance in the mother
Which patients are prone to ketoacidosis?
Type 1
Which patients usually are diagnosed through the complications that have arisen as a result of their diabetes?
Type 2
Who gets screened for T2 diabetes?
- Women with previous gestational diabetes - People aged 65 and over - Afro caribbean and south asians aged 35 and over - People over 50 who have BMI>30, T2DM first degree relative or hypertension - People with clinical cardiovascular disease - Women who are obese and have polycystic ovary syndrome
What measures can reduce microvascular complications of diabetes?
Tight blood glucose control (FBG<5.5)
What measures can reduce microvascular complications of diabetes?
Tight blood pressure control (<130/80)
What measures can decrease the incidence of cardiovascular events in diabetes?
Control of lipids (T.chol<4)
What are the microvascular changes seen in diabetes?
Retinopathy, nephropathy, neuropathy, erectile dysfunction, absent foot pulses, ischaemic skin chances
What are the macrovascular changes seen in diabetes?
Ischaemic heart disease, cerebrovascular disease, peripheral vascular disease
How can diabetic foot be managed?
- Examine feet of all those with diabetes 2. Suspect: infection, fracture, ulceration, Charcot 3. Investigations: WBC, CRP, ESR, U&E, Swab, X-ray 4. Treatment: bed rest, IV abx, refer
What does infection cause DKA?
- Infection leads to high cortisol and catecholamines 2. These cause gluconeogenesis
How is DKA diagnosed?
Glucose > 11 mmol/l Ketones > 3 mmol/l Acidosis <7.3 pH
What is the pathophysiology behind DKA?
- Glucose cannot be broken down as there is no insulin 2. The body breaks down fatty acids to get ketones for energy 3. This causes acidosis
What are the signs and symptoms of DKA?
SYMPTOMS: Polyuria, polydipsia, weight loss, weakness, drowsiness, coma SIGNS: dehydration, hypovolaemia, increased respiration
What is the protocol for DKA?
ABCDE
- IV fluids
- IV fluids + potassium
- IV insulin infusion
- Investigations to see what causes DKA, treat cause
- Establish monitoring regimen
- Once insulin in normal range, switch to glucose-insulin infusion to prevent hypos
What are the pros and cons of the oral glucose tolerance test?
Pros - sensitive, early marker of impairment Cons - affected by short term lifestyle changes, expensive, takes time and effort
What are the pros and cons of the glycated haemoglobin concentration (HbA1c)
Pros - reflects long term glucose, unaffected by acute change, convenient, high correlation with risks of complication Cons - lower sensitivity, expensive, not recommended for rapidly progressing diabetes
What is metabolic syndrome?
Central obesity + 2 of: - High triglycerides - High BP - Low HDL - High fasting glucose - DM This can cause vascular events
How can glucose control be monitored?
HbA1c, finger prick test (if on insulin)
What is the definition of hypoglycaemia?
Plasma glucose <3
What are the symptoms of hypoglycaemia?
AUTONOMIC - sweating, anxiety, hunger, tremor, palpitations NEUROGLYCOPENIC - confusion, drowsy, seizures, coma
What causes hypoglycaemia EXPLAIN?
EXogenous drugs (insulin) Pituitary insufficiency Liver failure Addison’s disease Islet cell tumours Non-pancreatic neoplasms
How is a hypoglycaemic attack managed?
ABCDEFG (dont ever forget glucose) Conscious - oral glucose Unconscious - IV dextrose, glucogel, IM glucagon - monitor BMs every 15 min - give long acting carbohydrate - review medication
What is the target BP for diabetics?
Below 140/80
What are the features of background diabetic retinopathy?
Dots, blots and deposits
What are the features of pre-proliferative diabetic retinopathy?
Cotton-wool spots, haemorrhages and venous beading
What are the features of proliferative diabetic retinopathy?
New vessel formation
How can diabetes affect the eyes?
Retinopathy, maculopathy, blurred vision, cataracts, rubeosis iridis
What is rubeosis iris?
New vessel formation on the eye, leading to glaucoma
What are the signs of neuropathy in the feet?
Decreased sensation, absent ankle jerks, deformity
What is Charcot’s foot?
A condition in which sugar damages the bones of the foot, causing weakness
What is a hyperosmolar hyperglycaemic state?
T2DM - extremely high blood glucose causing severe dehydration, dry skin, confusion, coma
How is hyperosmolar hyperglycaemic state diagnosed?
Glucose >30mmol/l and ABSENCE OF DKA FEATURES (vomiting)
How is HH state managed?
IV fluids slowly and electrolyte replacement (potassium)
