T1 DM Flashcards
Type 1 Diabetes is a condition where the _____ stops being able to produce adequate _____
pancreas
insulin
Without insulin, the cells of the body cannot absorb ____ from the blood and use it as fuel
glucose
Therefore the cells think there is no glucose available.
Whilst the cells think there is no glucose available, the glucose level in the blood keeps rising causing ________
hyperglycaemia
Which viruses may trigger T1 DM?
Coxsackie B
Enterovirus
What are the triad of symptoms of hyperglycaemia?
Polyuria (excessive urine)
Polydipsia (excessive thirst)
Weight loss (mainly through dehydration)
What are some other symptoms of T1DM?
Polyphagia (increased hunger)
Glycosuria (glucose in urine)
Fatigue and weakness
Burred vision
Irritability
Where are carbohydrates like glucose absorbed?
Small intestine
What is the ideal blood glucose concentration range?
4.4 - 6.1 mmol/litre
What is RPG and FPG?
Random plasma glucose and Fasting plasma glucose (not eating for at least 8 horus)
What is a normal level of glucose for RPG?
Lower than 11.1 mmol/l
(so 11.1 mmol/l or more in T1DM)
What is a normal level of glucose for FPG?
Lower than 7.0 mmol/l
(so 7.0 mmol/l or more in T1DM)
Which cell produce insulin?
Beta cells in the Islets of Langerhans of the pancreas
True of false: insulin is a catabolic hormone
False
Insulin is an anabolic (building) hormone.
Insulin causes cells in the body to absorb glucose and use it as fuel.
It also causes _____ and ____ cells to absorb glucose and store it.
muscle and liver
What is glucose stored as in the liver and muscle?
Glycogen
What is the process of glucose being stored as glycogen called?
Glycogenesis
What hormone is produced by alpha cells in the islets of Langerhans in the pancreas?
Glucagon
True or false: glucagon is a catabolic hormone?
True, its a breakdown hormone
When is glucagon resleased?
In response to low blood sugar levels and stress
True or false: glucagon work to increase blood sugar levels
true
Glucagon causes the liver to break down stored glycogen into the blood as glucose in a process called
glycogenolysis
Glucagon also instructs the liver to (other than glycogenolysis)…
Convert proteins and fats into glucose in the process of gluconeogenesis
When does ketogenesis occur?
When there is insufficient glucose supply and the glycogen stores are exhausted (eg prolonged fasting)
What is ketogenesis the conversion of?
fatty acids in the liver to ketones
What are properties of ketones?
Water-soluble fatty acids that can be used as fuel.
Can cross the BBB and be used by the brain
How can ketone levels be measured?
Ketones in urine with dipstick
Ketones in blood with ketone meter
What is a characteristic trait of people in ketosis?
Acetone smell to their breath
How is the acidity of the ketones in the blood countered?
The kidney buffer ketone acids
What is the life-threatening metabolic acidosis as a result of extreme hyperglycaemic ketosis called?
Diabetic ketoacidosis
What can you look for in a T1DM patient to differentiate from T2DM patient?
Autoantibodies:
Anti-islet cell antibodies
Anti-GAD antibodies (glutamic acid decarboxylase)
Anti-insulin antibodies
How is T1DM managed long-term?
Subcutaneous insulin
Monitoring dietary carbohydrate intake
Monitoring blood sugar levels
Monitoring for and managing complications
How is insulin delivered?
Subcutaneously
(Basal-bolus regime or through pump)
When should the blood sugar levels be monitored?
Upon waking
At each meal
Before bed
What is the basal-bolus regime?
Long-acting insulin injected once a day
Short-acting insulin injected 30 mins before consuming carbs (meals)
What can happen if insulin is consistently injected at the same spot?
Lipodystrophy, where subcutaneous fat hardens, don’t absorb insulin properly.
What are insulin pumps?
Devices that continuously infuse insulin through a cannular inserted under the skin at different rate to control blood sugar levels. Alternative to basal-bolus regimes. The cannula is replaced every 2-3 days
What are advantages of an insulin pump?
Better blood sugar control
More flexibility with eating
Fewer injection
What are disadvantages of an insulin pump?
Difficulties learning to use the pump
Having it attached at all times
Blockages in the infusion set
Small risk of infection
True of false: for a pancreas transplant, the diabetic patient’s pancreas is removed in place with a donor’s pancreas to produce insulin
False
the original pancreas is left in place to continue producing digestive enzymes, the donor’s pancreas is implanted to produce insulin.
Procedure carries significant risks and life-long immunosuppression to prevent rejection. Therefore, saved for patients having severe hypoglycaemic episodes and kidney transplants.
True or false: islet transplantation involves inserting donor islet cell into the patient’s pancreas.
False, inserted into patient’s liver. These produce insulin although patients will often still need insulin therapy.
What is glycated haemoglobin?
Haemoglobin molecule attached to glucose
What is the measurement of glycated haemoglobin called and what does it indicate?
HbA1c
Reflect the average glucose level over previous 2-3 months.
Measured every 3 to 6 months.
What level of HbA1c indicates T1 DM?
48 mmol/l or more
How can you measure capillary blood glucose?
Finger-prick test using blood glucose monitor
Flash glucose monitors (eg FreeStyle Libre 2) use a sensor on the skin that measures the glucose level of the ______ ____ in the subcutaneous tissue
interstitial fluid
What is the time lag for flash glucose monitors?
5 minutes
Sensor records glucose readings at short intervals. Can be read by using phone.
Sensor need replacing every 2 weeks.
What does an artificial pancreas of closed-loop system refer to?
Combination of continuous glucose monitor and insulin pump. Devices communicate automatically to adjust insulin based on glucose readings. Still need to input carbohydrate intake and adjust for strenuous exercise.
H____glycaemia may be caused by too much insulin
Hypoglycaemia
What other factors may lead to hypoglycaemia?
Not consuming enough carbs, malabsorption, diarrhoea, vomiting.
What are symptoms of hypoglycaemia?
Hunger, tremor, sweating, irritability, dizziness and pallor
Severe: reduced consciousness, coma and death
How do you treat hypoglycaemia
Rapid-acting glucose (eg high sugar content drink)
Then slower-acting carbohydrates (eg biscuits).
If severe: IV dextrose, intramuscular glucagon
Too much or too little insulin can cause hyperglycaemia?
Too little insulin
Insulin injections can take several hours to take effect and repeated doses may lead to hypoglycaemia.
Exclude DKA!
Chronic high blood glucose levels can cause damage to…
endothelial cells of blood vessels = leaky vessels that are unable to regenerate
Also cause immune system dysfunction and create optimal environment for infectious organisms to thrive.
What are microvascular complications from diabetes?
Coronary artery disease
Peripheral ischaemia
Diabetic foot ulcers (due to peripheral neuropathy)
Stroke
Hypertension
Due to hyperglycaemia (which activates RAAS system resulting in hypertension), inflammation and dyslipidaemia contributing to atherosclerosis
What are microvascular complication from diabetes?
Peripheral neuropathy (nerve damage)
Retinopathy (hyperglycaemia damages blood vessels in retina)
Kidney disease eg glomerulosclerosis (due to hyperglycaemia)
What are some infection-related complications?
UTIs
Pneumonia
Skin and soft tissue infections
Fungal infections eg oral or vaginal candidiasis
In retinopathy, hyperglycaemia can damage the small blood vessel in the retina causing them to leak fluid or bleed. This can result in _____ of the retina and formation of abnormal blood vessels, impacting vision
swelling
What kind of hypersensitivity is T1DM?
Type 4 hypersensitivity, autoimmune destruction of pancreatic beta cells
T1DM is an ______ insulin deficiency, though to be triggered by an _____ factor eg virus
absolute
environmental
What is the aetiology of T1 DM?
Young, lean, North European descent (Finland)
What are risk factors for T1 DM?
HLA DR2DQ3
HLA DR2DQ8
Other autoimmune conditions
environmental infection
What is transported with glucose into cells in response to insulin?
Potassium
In insulin deficiency the potassium levels may become…
elevated (hyperkalaemia)
No insulin to stimulate uptake of K+ into cell
Persistent hyperglycaemia can lead so o_____ d____, where glucose is excreted in urine, dragging water and electrolytes like potassium with it, potentially causing h____
Osmotic diuresis
hypokalaemia
DKA is increased ketone bodies due to breakdown of fatty acids. As ketone bodies are excreted, they carry potassium ions with them, potentially leading to…
hypokalaemia
How can excessive insulin impact potassium?
Can cause shift of k+ into cells causing hypokalaemia
