type 1 diabetes mellitus

Question 1

describe the difference between type 1 and type 2

Answer 1

• 1: complete lack of insulin
• 2: relative lack of insulin and insensitivity
• diabetic ketoacidosis is only a feature of T1DM

Question 2

why is there no ketacidosis in T2DM?

Answer 2

insulin production is sufficient to supress ketone production

Question 3

in pathogenesis, what is the honeymoon phase?

Answer 3

last instance where the beta cells produce a non-hyperglycaemic response with just enough insulin

Question 4

how do T cells cause destruction?

Answer 4

• effector T cells are destructive
• T-reg cells are supposed to keep effector T-cells in check
• eventually T-effector cells overcome T-reg cells and destruction occurs

Question 5

as patients with T1 have an immune background, what does this mean?

Answer 5

• inc. prevalence of other AI disorders
• risk of AI in relatives
• more destruction of beta cells
• can measure auto-antibodies to confirm T1DM and can treat autoimmunity

Question 6

which gene mutations pose a significant risk to getting T1DM?

Answer 6

HLA-DR3 and HLA-DR4 deletions

Question 7

what are the markers for T1DM?

Answer 7

• islet cell antibodies
• insulin antibodies
• glutamic acid decarboxylase
• insulinoma-associated-2 autoantibodies receptor like family

Question 8

what are the symptoms of T1DM?

Answer 8

• polyuria, nocturia
• polydipsia
• blurring of vision
• thrush
• weight loss
• fatigue

Question 9

what are the signs of T1DM?

Answer 9

• dehydration
• cachexia (muscle wasting, weakness)
• hyperventilation
• ketone smell
• glycosuria, ketonuria

Question 10

what is the action of insulin?

Answer 10

• released post-prandial
• acts to absorb glucose into cells
• creates stores of energy

Question 11

what is the effect of insulin on adipocytes?

Answer 11

• insulin inhibits glycerol leaving adipocytes

- deficiency of insulin enables glycerol to leave cells and TGs break down

Question 12

what does the lack of insulin do?

Answer 12

• allows FFAs to escape adipocytes and so are turned into ketone bodies inside liver
• ketone bodies are then taken up by muscle and brain but also cause ketonuria

Question 13

what are the aims of treatment?

Answer 13

• reduce early mortality
• avoid acute metabolic decompensation
• prevent long term complications

Question 14

what diet changes?

Answer 14

• reduce calories as fat and refined carbohydrate
• inc. calories as complex carbs and inc. soluble fibre
• distribute food evenly throughout day with regular meals and snacks

Question 15

when should insulin treatment be given?

Answer 15

• meals: short acting insulin

- background: long acting insulin and can be non c-bound to zinc/protamine

Question 16

what are insulin pumps?

Answer 16

• give continuous delivery
• have pre-programmed basal andbolus rates
• do not measure glucose feedback

Question 17

what are islet cell transplants?

Answer 17

• donor can donate some pancreas islet cells
• inserted into diabetic’s liver portal vessels to release insulin
• pt must be on continuous immunosuppression
• treatment is only reserved for those with erratic control of diabetes

Question 18

what is capillary monitoring?

Answer 18

either via a continuous monitor attached to belly

or through finger pricks

Question 19

what is HbA1C red cell monitoring?

Answer 19

• glucose binds to RBCs irreversibly so can give a long-term view of glucose control

Question 20

what are 3 acute complications?

Answer 20

• metabolic acidosis (keotacidosis)

- hyperglycaemia (reduced tissue glucose utilisation and inc. HGO)

Question 21

what is metabolic acidosis due to?

Answer 21

• circulating acetoacetate/hydroxybutyrate and osmotic dehydration and poor tissue perfusion

Question 22

what is hypoglycaemia?

Answer 22

<3.6mmol/L glucose
mental processes impaired at <3mmol/L
coma <2mmol/L

Question 23

who do hypos affect?

Answer 23

• low quality hypoglycemic control patients

- more common in patients with low HbA1C

Question 24

why do hypos strike?

Answer 24

• new exercise
• missed meals
• inadequate snacks and alcohol
• bad insulin regime

Question 25

what are the symptoms of hyperglycaemia?

Answer 25

inc. autonomic activation:
- palpitations
- tremor
- sweating
- pallor/cold extremities
- anxiety
impaired CNS functions:
- drowsiness
- confusion
- altered behaviour
- coma

Question 26

what is the hypoglycaemia treatment?

Answer 26

• oral: glucose, complex carbs

- parenteral (give if consciousness impaired): IV dextrose, 1mg glucagon IM