Overview of Diabetes Flashcards
(37 cards)
Define diabetes
Chronic hyperglycaemia @ levels to cause specific microvascular complications
How is diabetes diagnosed?
Test on 1 occasion if symptomatic, 2 if asymptomatic
Need 1 of:
- Fasting plasma glucose > 7
- Random plasma glucose > 11.1
- HbA1c > 6.5%
What are the symptoms of diabetes?
- Polydipsia/polyuria - increased osmotic load
- Blurred vision - increased fluid build up in lens
- Thrush
- (Weight loss in T1 only) - catabolic state > fat break down
What is pre-diabetes?
- Impaired glucose tolerance (fasting < 7 AND 2hr 7.8-11)
2. Impaired fasting gcylaemia (>6)
What are the types of diabetes?
- T1
- T2
- Gestational
- Other - MODY, exocrine pancreas disease, endocrinopathies, genetic…
What are the key features of T1D?
- B cell destruction > absolute insulin deficiency
- Immune mediated
- Anti-GAD, IA2, ZnT8, Anti-insulin
- Idiopathic
- Chronic
- Rapid onset
- Ketosis prone
What is T2D?
Ranges from predominantly insulin resistance with relative insulin deficiency > predominantly secretory defect with insulin resistance
What are the micro-vascular complications of diabetes?
Retinopathy
Nephropathy
Neuropathy
What are the genetics of T1D?
HLA DR3/4 predisposition
Caucasian
3/4 male
What are the acute complications of diabetes?
- DKA
- Hyperglycaemia, hyperosmolar syndrome
- Hypoglycaemia
What blood glucose is considered hypoglycaemia?
< 4
< 2.5 = loss of consciousness
What blood glucose is considered hyperglycaemia?
> 8
What is the definition of DKA?
- Hyperglycaemia (BS > 11)
- Ketonaemia (> 3)
- Acidosis (either pH < 7.3, HCO3 < 15)
Low glucose = increased BG so start producing ketone bodies as source of fuel = acidic so pH drops
How is DKA treated?
- IV fluids +
- Insulin
- K+ replacement (as insulin moves K into cells so it can drop)
What are the causes of death in DKA?
- Cerebral oedema esp in children
- Underlying condition - sepsis, ARDS, MI
- Hypokalaemia
What is the presentation of hypoglycaemia?
- Autonomic = sweating, palpitations, shaking, hunger
- Neuroglycopenic = confusion, drowsiness, odd behaviour speech difficulty, incoordination
- General malaise = headache, nausea
How do you treat hypoglycaemia patients which are conscious, orientated + able to swallow?
- Quick acting CHO
- If BS remains low need parental therapy
- After BS > 4 give long acting CHO
How do you treat hypoglycaemia patients who are unconscious/aggressive/seizures?
- IV therapy
- After BS > 4 give long acting CHO
What are the macro-vascular complications of diabetes?
- IHD
- Peripheral vasc disease
- Stroke
What is HbA1c?
- Glycosylated haemoglobin
- Reflects average plasma glucose over 8-12 weeks
- Accurate measure of chronic glycaemia levels (but shouldn’t be used in diagnosis if T1D, symptom onset within 2m, haemolytic anaemia + haemoglobinopathies)
What is a basal bolus regime?
- Slow acting insulin which lasts throughout day
- Short acting insulin with each meal
What are the key points of the endocrine system?
- Broadcasts hormonal messages by secretion into blood + CSF
- Negative feedback
Which are the hypothalamic releasing hormones and what effect do they have on the pituitary?
- Corticotrophin releasing hormone (CRH) > ACTH secretion
- Thyrotropin releasing hormone (TRH) > TSH & Prolactin secretion
- Growth hormone releasing hormone (GHRH) > GH secretion
- Somatostatin > Inhibits GH secretion
- Gonadotropin releasing hormone (GnRH) > LH + FSH secretion
- Prolactin releasing hormone (PRH) > PRL secretion
- Prolactin inhibiting hormone (dopamine) > Inhibits PRL secretion
What are the characteristics of hypothalamic releasing hormones?
- Pulsatile secretion
- Transduce signals via 2nd messengers
- Stimulates release and synthesis of pituitary hormones
- Induces hyperplasia and hypertrophy
