Diabetes Flashcards
List the 4 types of Diabetes
Type 1: Autoimmune, Idiopathic. Deficiency of insulin secretion.
Type 2: Insulin resistance + insulin deficiency + insulin secretory defect
Type 3: Defects in B-cell function, insulin action or disease of exocrine pancreas
What is the migrant effect?
If a child is born in a low incidence region & moves to a high incidence country, they will adopt high incidence.
Therefore it hints at an environmental trigger.
What is the incidence of type 1 DM in ireland
28.8
Epidemiology of T1DM
50% will be diagnosed before 15 y.o
Bimodal distribution in ireland. Peaks in 5-6 years & 12-14.
Doubling cases of under 5s diagnosed from 2005 to 2020.
What is the % risk if a 1st degree relative has T1DM
12-15%
6% if father affected
2% if mother affected
What genes contribute to the risk of developing T1DM
HLA-DR3 - 8-10x
Which type of diabetes is prone to ketoacidosis?
Type 1 Diabetes
When do patients start to become clinically symptomatic?
whe ~90% of B cells are destroyed
Pancreatic islet B cell destruction is mediated by which cell?
T-cell.
How does hyperglycaemia cause polydipsia
Glucosuria –> polyuria (because glucose is a osmotic molecule that draws water out) –> dehydrated –> polydipsia
Symptoms of diabetes
Polyuria Polydipsia Weight loss Eneuresis. Usually secondary. - Dip urine Constipation dehydration Candidiasis
Symptoms of DKA. Clinical signs of DKA
Vomiting
Abdo pain
Impaired consciousness (from ketones)
Weakness
Clinical signs:
- Dehydration
- Smell of ketones
- Lethargy
- Drowsiness
- Kussmal breathing
Biochemistry for DKA
Metabolic acidosis
Hyperglycaemic. Random > 11.1 mmol/l
Ketones > 3
What is done to diagnosis diabetes?
OGTT
Fasting > 7.0mmol/l
2hr post-prandial > 11.1
What are the impaired fasting glycemia levels?
fasting levels of: 6-7.
What is the Impaired glucose tolerance (IGT) levels
2 hr post prandial: 7.8-11.1
What initial investigations to work up a patient with polydipsia & polyuria?
Bloods:
- FBC, CRP (looking for signs of infection that could raise blood cortisol or glucose)
- Random plasma glucose
- Ketone levels
- VBG
- Electrolytes (hypok+ in DKA)
- HbA1c: average 3 months of glucose control
- Auto - Antibodies: ICA, IAA, GAD, ZnT8
- Screening for other autoimmune diseases
Urine:
- Urine for ketones, glucose
What % of patients have ICA, IAA, GAD auto anti-bodies
What is ZnT8
ICA: Islet cell abx 60-90%
IAA: Insulin autoantibody (30-40%)
GAD: 65-80%
ZnT8: specific for pancreas
What is the management for fluids in the mx of DKA?
1st hour –> fluids
2nd hour –> Insulin
When peeing, give K+ supplements
What to monitor in a ptx with DKA?
K+ levels every hour, 2 hourly then 4 hourly Monitor for signs of: - sepsis - neurological deterioration - cerebral oedema
Follow up goals for T1DM
- at least 4 daily fingerprick tests
- Aim pre-prandial for 4-8 mmol/l
- Aim post-prandial: > 10.0
- Monitor sugars more often during intercurrent illness
- HbA1c < 7.5%
What additional conditions have to be screened for and how often?
Yearly: thyroid & coeliac
If they are 10 y.o, every 2-5 years:
- Retinopathy
- Nephropathy (microalbuminuria, BP) - take early morning sample. Also do protein : Creatinine ratio.
- Neuropathy
- Lipids
Short term complications with T1DM
Hypoglycaemia
DKA
Sick Days
Lipohypertrophy
Long term complications
Retinopathy, nephropathy, neuropathy, macrovascular
Impaired growth & development Late puberty Obesity (too much insulin) Autoimmune conditions: - Hypothyroidism / Hyperthyroidism - Coeliac - Addison's (Autoimmune adrenal failure)
