Diabetes Pathology Flashcards Preview

Semester 4 (NME) > Diabetes Pathology > Flashcards

Flashcards in Diabetes Pathology Deck (82):
1

What % of diabetic patients have T1DM?

15%

2

What is the most common ethnicity of patients with T1DM?

Caucasion
North European

3

What is the most common age of presentation of T1DM patients?

Puberty
(But can be any age)

4

What is the pathophysiology of T1DM?

Gradual destruction of Bcells due to autoimmunity

5

What is the most common subtype of T1DM?

Type 1A
Immune regulated form
90% have mutations in HLA genes on chromosome 6

6

Name a non genetic risk factor for T1DM?

Clean environment during childhood with little exposure to pathogens

7

Name 5 common symptoms of T1DM at presentation?

Polydipsia (increased thirst)
Increased urination (especially at night)
Weight loss/ fatigue
Itching around genitals/ bouts of thrush

8

Name 3 signs of diabetic patients seen at presentation?

Hyperglycemia
Glucosuria
Ketoneuria?

9

Name 6 emergency signs in a presentation of T1DM?

Loss of appetite/ N+V
Fever/ drowsy/ confused
Stomach pain
Fruity (pear drop) breath - ketoacidosis

10

What glucose levels (fasting and random) indicate possible diabetes?

Random glucose >11.1mmol/L
Fasting glucose >7mmol/L

11

What are the diagnostic criteria for T1DM when doing glucose tests?

ONE random/ fasting glucose out of range if symptomatic
TWO randon/fasting glucose out of range if asymptomatic

12

What HbA1c level is diagnostic of diabetes?

>48mmol/L (6.5%)
Although result lower than this does not exclude diagnosis if glucose test disagrees

13

What is the treatment for T1DM?

Always need insulin!
Education/ healthy diet/ weight loss/ smoking cessation

14

What are the two different methods of insulin dosing?

Twice Daily: Intermediate insulin (isophane)
- Works within 2hrs, lasts 18-24hrs
Multiple Dose: Rapid acting insulin
- Best for Px with good understanding/ control

15

Px taking insulin on a multiple dose regimen should take their insulin when?

Before/ with a meal

16

What is the main type of twice daily insulin?

Hypurin isophane (either bovine or porcrine)

17

Name the two most common rapid acting insulins?

Novorapid
Humalog (works in 15mins)
Lasts 3-5hrs

18

What is analouge insulin?

Similar to human but with recominant DNA
(Where AA's have been changed to change insulin properties)

19

What is HbA1c?

A reliable indicator of mean glucose levels over the last 120 days

20

Why can HbA1c be used to give estimates of glucose?

As glycation (adding of sugar) to the Hb occurs at a variable rate over an RBC's 120 day lifespan, so proportions of glycated reflect how much sugar has been in the blood

21

What is the normal level of HbA1c?

4-6% (20-43mmol/L)

22

Name 8 symptoms of hypoglycemia?

Shaking/ sweating
Weakness/ confusion
Hunger/ tingling lips
Slurred speech/ unconciousness/ transient hemipariesis

23

How would you treat a hypoglycemic patient when in a hospital?

If mild treat sugary drinks/ food
Give 80ml of 20% glucose IV

24

How would you treat a hypoglycemic patient when not in a hospital?

If mild give sugary drinks/ food
1mg (1unit) glucagon intramuscular

25

Name 4 risk factors than can predispose a diabetic patient to have a 'hypo':

Exercise
Taking too much insulin
Drinking alcohol on an empty stomach
Skipping meals

26

What is the clinical definition of hyperglycemia?

Blood glucose >11.1mmol/L

27

What is the classic triad of symptoms of hyperglycemic Px?

Polyphagia (hunger)
Polydipsia (thirst)
Polyuria (frequent urination)
(Add diabetic symptoms/ dry mouth/ drowsiness)

28

Prolonged hyperglycemia can lead to (5)?

Diabetic ketoacidosis
Renal/ cardiovascular/ neural/ retina damage

29

What is the pathophysiology of T2DM?

Disorder of receptors (increased triglyceride levels can cause release of inflam proteins/cytokines which damage 2nd messengers). Hyperinsulinaemia initially compensates but this eventually leads to Bcell damage

30

What % of patients with DM have T2DM?

90%

31

What ethnicity is most subceptible to T2DM?

Afrocarribean

32

Name 7 RF's for developing T2DM:

'Central' obesity/ lack of physical activity
Low fibre, high sugar diet/ metabolic syndrome
Family history/ Polycystic ovary syndrome
Low birth weight/ gestational diabetes

33

How does presentation of T2DM differ to those with T1DM?

Longer onset of symptoms
Px with T2 often present much later in life

34

Name 6 presenting complaints for Px with T2DM:

Polyuria/ polydipsia/ lethargy
Boils/ prolonged infections
Pruritus vulvae (itchy genitals)

35

What is the NICE recommended treatment pathway for Px with T2DM?

Diet control > metformin >
Metformin + sulfonylurea (or DPP-4 inhib if hypo risk)
> add thiazolidinedione or insulin

36

What is metformin, how does it act, when is it given and what is a possible SE?

Activates AMPK (AMP activated protein kinase) in the liver and muscle to upregulate GLUT-4 receptors
Take orally w meals
SE: Lactic acidosis

37

How do sulfonylurea drugs work?

Bind to ATP sensative K+ channels on B cells, this depolarises the cell and opens Ca2+ channels which increases insulin release

38

Name three sulfonylurea drugs:

Glimepiride / Glipizide / Tolbutamide

39

How do DPP-4 inhibitor drugs work?

Inactivates the enzyme which inactivates GLP-1 (an incretin)
- This increases levels of GLP-1 which along with GIP causes the incretin effect

40

Name 2 DPP-4 inhibitor drugs:

Linagliptin/ Saxagliptin

41

How do thiazolidinediones act? Give an example drug

Act on intracellular receptor PPAR-Y to decreases hepatic glucose production and increase uptake and use in muscle
E.g Pioglitazone

42

What is the common presentation of diabetic ketoacidosis?

Diabetic symptoms (+ dehydration )
Drowsy/ confused/ fruity breath
Tachycardia/ hyperventilation/ hypotension

43

How common is gestational diabetes, what care should be taken to ensure women are protected?

Roughly 1in35 pregnancies- commonly in 2nd trimester
Ensure all high risk women are screened
Monitor and advise on diet, treat if needed (insulin)

44

What is the pathophysiology of diabetic retinopathy?

Usually in 2nd decade of disease
Vascular microaneurysms (permeability changes etc lead to blood flow changes and ischemia)

45

What is the most common presentation of diabetic neuropathy?

Distal symmetrical polyneuropathy, starting with distal sensory loss

46

What is the pathophysiology of diabetic foot ulcers?

Loss of sensation = more trauma
Anhidrosis = drying and skin damage
Disordered proprioception = abnormal weight bearing

47

What are common diabetic dermatological problems?

The most common skin manifestations of DM are protracted wound healing and skin ulcerations

48

Where is acetyl-coA converted into ketone bodies in diabetic ketoacidosis?

Mitochondria

49

Soluble insulin produces what effect?

Rapid acting and short lasting

50

How are insulin preperations made to act over longer time periods?

Precipitating insulin with protamine or zinc

51

What % of T2DM will ultimately take insulin as part of the treatment?

33%

52

Which brain area links the osmoreceptors in the ant hypothalamus with the ADH releasing cells in the post pituitary?

Supraoptic nuclei

53

Which two area's of the brain regulate hunger?

Lateral nuclei of hypothalamus = feeding centre (stimulation = hunger)
Ventromedial nuclei of hypothalamus = satiety centre (stimulation = feel full)

54

Multiple hormones released from the gastrointestinal tract and adipose tissue converge to regulate food intake as well as energy expenditure- where is this?

Arcuate nuclei

55

Which of the ketone bodies can't be used by the cells and converted back to acetyl-coA, what happens to it?

Acetone
Instead it is expired via the lungs

56

What is the pathophysiology of diabetic nephropathy?

Renal hypertrophy associated with incr GFR (as afferent arteriole becomes more dilated), this raises intraglomerular pressure and damages cappilaries causing glomerular sclerosis

57

What are some common signs of diabetic nephropathy? (3)

Microalbuminuria (1st) > intermittenent albuminuria (2nd) > proteinuria (3rd)
Hyperlipidemia/ generalised oedema

58

How should diabetic nephropathy be treated?

ACEI
Aim below 130/80mmHg

59

What is the pathophysiology of diabetic neuropathy?

Hyperglycemia can lead to build up of 'sorbitol' and fructose in schwann cells- this leads to demyelination

60

How does diabetic neuropathy usually present?

Loss of vibration/ pain/ temp (usually feet before hands)
Feeling of walking on cotton wool
Balance impaired in the dark (less proprioception)

61

What is the pathophysiology of diabetic foot and how common is it?

10-15% of diabetic patients
Due to combination of ischemia (macrovascular), infection and neuropathy
(Black feet = vascular problem)

62

How should you treat diabetic foot?

Keep weight off ulcers
Treat with AB's if needed

63

How common is diabetic eye disease?

90% of T1DM Px go on to develop

64

What is diabetic retinopathy?

Nerve damage to retina/ iris damage
Due to intramural pericytes death and basement membrane thickening (so less blood supply to nerves)

65

What are cateracts?

Denaturing of proteins in the lens render it opaque
(increased risk in diabetes and ketosis)

66

What is the recommendation for all patients with diabetes in regards to observing for opthalmic changes?

All diabetic Px should have yearly eye screening

67

How does blood glucose testing equipment work?

Has 'glucose oxidase' which catalyses the reaction of glucose to gluconic acid. Gluconic acid is measured and then the equipment converts this into a glucose level

68

Where should the Px prick when doing a glucose test?

Side of finger

69

How often should Px with T2DM which is controlled by diet/ oral agents measure their glucose?

Once/twice per week

70

How often should Px on insulin treatment check their glucose levels?

~12 hours after long acting insulin dose or
~ 90mins-2hrs after short acting insulin dose
2-4x per day

71

What % of patients on insulin therapy die due to their diabetes?

86%

72

What are the three main causes of death in diabetic patients?

CVD- 70%
Renal- 10%
Infection- 6%

73

Name 4 macrovascular complication of diabetes?

Stroke
MI
Foot gangrene
Atherosclerosis

74

Name 3 BV area's commonly affected by microvascular disease in diabetes?

Retina
Kidney
Nerve sheaths
(often ~10-20 years post diagnosis)

75

Why do alcohol binges predispose to hypoglycemic attacks?

Alcohol reduces the livers ability to cope with change to glucose levels in plasma so there's reduced release of glucose into the blood when your drunk.

76

What is the best test to determine a Px's glucose control over the last 2-3hours?

Glucosuria test

77

Which test would best establish a patient's current level of glycaemic control?

Blood glucose test

78

Which test would best establish a Px's long term level of glycaemic control?

Haemoglobin A1c test

79

What is the most common SE of metformin?

GI disturbance

80

What is the most common SE of sulfonylurea's?

Hypoglycemia

81

Px w T1DM should aim for what blood glucose levels (pre and post prandial)?

Pre: 4-7mmol/L
Post: Under 9mmol/L

82

What is the clinical definition for hypoglycemia?

Glucose levels under 3mmol/L