Diabetes Flashcards
1
Q
Define diabetes mellitus?
A
- An elevation of blood glucose above a diagnostic threshold
2
Q
What is the threshold for diabetes diagnosis based upon?
A
- The risk of developing retinopathy
3
Q
For the diagnostic criteria of diabetes mellitus what is the critical value for fasting plasma glucose that defines diabetes?
A
- Fasting plasma glucose >7mmol/L
4
Q
For the diagnostic criteria of diabetes mellitus what is the critical value for 2hr plasma glucose that defines diabetes?
A
- 2 hour plasma glucose >11.1 mmol/L
5
Q
For the diagnostic criteria of diabetes mellitus what is the critical value for HbA1c that defines diabetes?
A
- HbA1c > 48mmol/L
6
Q
What is gestational diabetes referring to?
A
- Diabetes during pregnancy
- Risk to fetus
7
Q
The diagnostic criteria for gestational diabetes is __lower/higher___ than that for diabetes mellitus?
A
- Lower
8
Q
Insulin is secreted from___
A
- beta cells in the pancreatic islet in response to blood glucose levels
9
Q
Insulins main function is to___
A
- lower blood glucose levels
10
Q
Glucagon is secreted from____
A
- alpha cells in the pancreatic islet in response to blood glucose levels
11
Q
Glucagon ____ blood glucose levels?
A
- Increases blood glucose level
12
Q
Explain c-peptide
A
- Useful way to measure endogenous insulin
- c-peptide + insulin = pro-insulin, which is then cleaved to produce insulin
- c-peptide is not found in injectable insulin therefore is a marker of insulin production
13
Q
What are the 2 scales of diabetes?
A
- Failure of production of insulin
- Insulin resistance
14
Q
Name some disorders of insulin secretion?
A
- type 1 diabetes
- MODY
- Pancreatitis caused by alcohol, CF, haemochromatosis
15
Q
Name some disorders of insulin action
A
- Donohue-syndrome
- obesity
- type 2 diabetes
- NAFLD
16
Q
Type 2 diabetes is __homogenous/heterogenous___
A
- highly heterogenous
17
Q
Type 1 diabetes is characterised by what?
A
- pancreatic autoantibodies
- autoimmune condition of beta-cells
- anti GAD
- 1A2
18
Q
What are some symptoms of diabetes?
A
- polyuria
- thirst
- blurred vision
- fatigue
- weight loss
19
Q
What microvascular complications are associated with diabetes?
A
- neuropathy
- retinopathy
- nephropathy
20
Q
What macrovascular complications are associated with diabetes?
A
- MI
- stroke
- PVD
21
Q
A HbA1c level of ___ in a diabetic indicates good control?
A
- 48mmol/mol
22
Q
What is the HbA1c blood test assessing?
A
- control of diabetes over 3 months (90 days)
- glycated haemoglobin which is proportional to sugar levels
23
Q
What will the affect of haemolytic anaemia have on the HbA1c test?
A
- reduced life-span of RBC
- not a true level of control
24
Q
What percentage weight loss can put diabetes type 2 into remission?
A
- 10-15%
25
Explain what is meant by a relative insulin deficiency in T2DM?
- Insulin resistance and beta cell dysfunction
26
What are some environmental risk factors for T2DM?
- Obesity
- age
- pregnancy
- calorie dense diet
- sedentary lifestyle
27
How will the islet of langerhans appear in the microscope?
- highly vascularised
| - dense collection of cells
28
What do delta cells of the pancreas secrete?
- somatostatin
29
What is the role of somatostatin from the pancreas?
- inhibits both insulin and glucagon release
30
How does obesity affect insulin production?
- fat reduces insulin action
- beta cells produce more insulin as compensation
- long term compensation may lead to T2DM
31
What stabilises insulin vesicles within the beta cell before they are exocytosed?
- zinc
32
What would a long term diabetes pancreas appear like down the microscope?
- marked reduction in the quantity of beta cells
| - known as degranulation
33
1st phase of the biphasic release of insulin releases what type of insulin?
- readily releasable
34
Explain the cascade of low glucose in an alpha cell?
- low glucose
- K/ATP channels open
- Na+ gates open
- Ca2+ channels open
- glucagon exocytosis
35
What happens in the alpha cell when glucose is increased?
- Closure of K/ATP channel
- SGLT2
- Ca2+ gates closed
- no glucagon released
36
What is the role of glucagon?
- Acts on the liver to promote hepatic glucose production
| - raises blood glucose levels
37
Paracrine signalling requires___?
- the 2 cells to be close together
38
Explain the incretin effect?
- insulin secretion is greater from oral glucose relative to an isoglycaemic IV infusion
39
Name 2 incretin hormones?
- GLP-1
| - GIP
40
GLP-1 is released from what cells?
- L cells of the gut
41
Name a GLP-1 receptor agonist drug?
- liragluitde
42
How does GLP-1 RA drugs work?
- bind to GLP-1 GPCR
- Increases insulin secretion
- promotes beta cell proliferation
43
What other positive effects of GLP-1 RA are there other than insulin increase?
- reduced appetite
- delayed gastric emptying
- inhibition of glucagon secretion
44
What breaks down GLP-1?
- DPP 4
45
Name a DPP4 inhibitor drug?
- sitagliptin
46
Natural form of GLP-1 has a __long/short__ half life?
- short
| - for drugs analogues are given
47
Insulin resistance can be linked to what other conditions?
- diabetes
- neurodegenerative diseases
- chronic kidney disease
- gout
- heart failure
48
What is the gold standard for measurement of insulin sensitivity?
- Hyperinsulinemic-euglycemic clamp
49
Explain how the hyperinsulinemic-euglycemic clamp works?
- keeps glucose levels static
- fixed increased insulin dose
- measure how much glucose is required to maintain levels
50
More glucose required to maintain levels on the hyperinsulinemic-euglycemic clamp suggests what?
- good insulin sensitivity
51
What are the 3 insulin resistance mechanisms?
- impairment in insulin signalling
- inflammation
- hepatic insulin resistance
52
Monogenic diabetes is caused by what?
- a single gene mutation
53
Most common monogenic diabetes?
- MODY
| - mature onset of diabetes in the young
54
How many genes have been linked to neonatal diabetes?
- 35
55
What is the most common neonatal diabetes gene?
- KCNJ11
| - Mutations in K/ATP channel
56
Treatment of neonatal diabetes?
- off insulin
| - high dosage sulphonylureas
57
Acanthosis nigricans is found where and is a sign of what?
- found in flexural creases
| - sign go hyperinsulinaemic state
58
How many genes have been linked to MODY?
- 11 genes
59
MODY is autosomal ____
- dominant
60
MODY is characterised by what?
- beta cell deficiency
| - non-insulin dependant
61
Non-insulin dependant diabetes under the age of 25?
- MODY
62
Most common gene mutation in transcriptional factor MODY?
- HNF-1 alpha
63
Two types of MODY?
- Transcriptional factor
| - glucokinase mutation
64
Normal blood glucose in early childhood MODY? Normal fasting glucose
- transcriptional factor MODY
65
MODY that won't respond well to a glucose tolerance test?
- Transcriptional factor
66
Treatment of transcription factor MODY?
- Off insulin
| - low dose sulphonylureas
67
KCNJ11 mutation associated with what?
- neonatal diabetes
| - permanently open K/ATP channels
68
HNF-1alpha patients are 4 times more sensitive to ____ that patients with T2DM?
- Sulphonylureas
69
Glucokinase in the beta cell is the ___
- Rate determining step
70
In glucokinase MODY homeostatic level of glucose is ___higher/lower___ than the normal population?
- higher
| - graph shifted to the right
71
Glucokinase MODY responds well to glucose challenge testing?
| TRUE OR FALSE?
- TRUE
| - they can produce enough insulin if challenge enough
72
Distinct high fasting glucose in a new born who responds well to a glucose challenge/tolerance test, suggests what?
- Glucokinase mutation MODY
| - Stable hyperglycaemia
73
Treatment of glucokinase MODY?
- Off insulin
| - no treatment
74
Why is no treatment given to glucokinase MODY?
- Glucokinase receptors in brain still work and programmed to hyperglycaemia, will counteract any drug given
- no complications associated with glucokinase MODY so no need for treatment
75
In glucokinase MODY the beta cell is functionally not working?
TRUE OR FALSE?
- FALSE
- homeostatic hyperglycaemic
- can produce enough insulin in challenge
- beta cell is normal otherwise
76
What occurs during the annual screening appointment of diabetics?
- digital retinal screening
- foot risk assessment
- albumin:creatinine ratio
77
What is the complications of hyperglycaemia?
- excess glucose with mitochondrial dysfunction leads to build up of reactive oxygen species
78
What eye diseases are associated with diabetes?
- diabetic retinopathy
- diabetic macular oedema
- cataracts
- glaucoma
- acute hyperglycaemia
79
Haemorrages on fundoscopy appear as what?
- dot
- blobs
- flames
80
Cotton wool spots on fundoscopy indicates what?
- ischaemic areas
81
Hard exudates on fundoscopy indicates what?
- lipid breakdown products
82
What is the 1st line treatment for retinopathy?
- laser
| - pan retinal photocoagulation
83
Explain laser pan retinal photocoagulation?
- reduces oxygen requirements of retina
| - reduces ischaemia
84
If laser pan retinal photocoagulation doesn't work in the treatment of retinopathy what may be done?
- vitrectomy
85
What is the first line treatment for diabetic macular oedema?
- intravitreal anti-VEGF
| - 2nd line - grid laser to macula
86
Explain nephropathy?
- progressive kidney disease cause by damage to the capillaries in the kidney's glomeruli
87
What are some consequences of nephropathy?
- development of hypertension
- decline in renal function
- accelerated vascular disease
88
Microalbuminuria is a ACR of what?
<30
89
Proteinuria is an ACR of what?
>30
90
How is microalbuminuria measured?
- not on normal urine dipsticks
- radioimmunoassay
- special dipsticks
91
How many positive results do you need to confirm diabetic microalbuminuria?
- 2/3 positive
92
What is the treatment of microalbuminuria?
- ACE inhibitors
- ARB
- SGLT2 inhibitors
93
Risk factors for neuropathy?
- increased length of diabetes
- poor glycaemic control
- high cholesterol
- smoking
94
Peripheral neuropathy has what distribution?
- glove and stocking
95
Symptoms of peripheral neuropathy?
- numbness
- tingling/burning
- sensitivity to touch
96
Consequences of peripheral neuropathy?
- painless trauma
- charcot foot
- foot ulcer
97
What are the 4 different types of neuropathy?
- peripheral
- proximal
- autonomic
- focal
98
Explain charchot arthropathy?
- destructive inflammatory process
| - deformity of the foot
99
Treatment of charcot arthropathy?
- total cast or air cast
100
Presentation of charcot arthropathy?
- swollen hot foot
101
Treatment for painful neuropathy?
- amitripyline
| - gabapentin
102
Autonomic neuropathy examples?
- gastroparesis
| - gustatory sweating
103
HbA1c gives an indication of glucose levels over how many weeks?
- 6-8 weeks
104
What is the target HbA1c for a diabetic?
- <53mmol/mol
| - <48mmol/mol in a younger pt
105
T1DM BG target in children and adults?
- before meal 4-7mmol/l
| - after meal 5-9mmol/l
106
T2DM BG target?
- before meal 4-7mmol/l
| - after meal <8.5mmol/l
107
Why is the insulin to carb ratio needed?
- to calculate the amount of rapid acting insulin needed to cover a specific amount of carbohydrate
108
What is the insulin sensitivity factor aka. correction factor?
- Used to calculate the drop in glucose for each unit of insulin
109
What are the benefits of self-monitoring glucose?
- glucose control
- lifestyle exercise
- carb counting
110
Benefits of continuous glucose monitoring?
- 24hr profile given
| - traces silent hypos
111
What are the 2 types of continuous glucose monitoring?
- Continuous
| - Flash
112
Why is it important to improve glucose control?
- Increased glucose control corresponds to a reduced risk of microvascular and macrovasular complications
113
What is diabetic ketoacidois?
- metabolic state that usually occurs in absolute or relative insulin deficiency --> lipolysis --> ketogenesis --> ketone bodies
114
What is the diagnostic criteria for diabetic ketoacidosis?
- ketonaemia >3mmol/L
- Blood glucose >11.0mmol/L
- Bicarbonate <15mmol/L
115
What are potential causes of diabetic ketoacidosis?
- infections
- inflammation
- intoxication
- infarction
116
Symptoms of DKA?
- Drowsiness
- polyuria
- polydipsia
- Kussmaul's respiration
117
Treatment of DKA?
- Fluids
- Insulin infusion
- potassium
118
Potential consequences of DKA?
- Arrythmia
- cerebral oedema
- ARDS
- Gastic ileus
119
What is normal blood ketone levels?
- <0.6mmol/L
| - ketosis = >3mmol/l
120
What causes hyperglycaemia hyperosmolar syndrome?
- unwell T2DM patient
| - electrolyte loss
121
Diagnosis of HHS?
- Hyperglycaemia >30mmol/l
- no ketonaemia <3mmol/l
- bicarbonate >15mmol/l
- osmolality >320
122
How is osmolality calculated?
2xNa + urea + glucose
- normal 275-295
123
Treatment of HHS?
- Fluids
- insulin (if ketones high)
- LMWH
124
Diagnosis of alcohol induced keto-acidosi?
- history of alcohol
- dehydration
- ketonaemia >3mmol/l
- bicarbonate <15mmol/l
- glucose normal or lo
125
Treatment of alcohol induced keto-acidosis?
- IV pabrinex
- IV fluids
- IV anti-emetics
126
Lactic acidosis is a blood lactate of?
- >5mmol/l
