What is Diabetes Mellitus? Flashcards
What are some of the characteristics of diabetes mellitus?
Hyperglycaemia
Defects in insulin secretion, insulin action, or bothq
RECAP- name the only hormone which lowers BG
Insulin
How does insulin lower BG levels?
Insulin switches off hepatic glucose output
Increases the insulin uptake of fat and muscle cells
What role does insulin have in adipose tissue?
Reduces lipolysis
What role does insulin have in muscle tissue?
Increases glucose uptake
List some of the symptoms of hyperglycaemia.
Polydipsia, polyuria, blurred vision, weight loss, infections
What are some of the microvascular long term complications of hyperglycaemia?
Retinopathy
Neuropathy
Nephropathy
What are some of the macrovascular long term complications of hyperglycaemia?
Stroke
MI
PVD- peripheral vascular disease
What is used to diagnose diabetes?
Measuring blood glucose or HbA1c
If taking a fasting glucose level, what level is diagnostic of diabetes?
> 7.0mmol/l
If taking a random glucose level, what level is diagnostic of diabetes?
> 11.1mmol/l
If taking an Oral Glucose Tolerance Test, what level is diagnostic of diabetes taken 2hrs after 75g carbohydrate?
> 11.1mmol/l
If taking a HbA1c level, what level is diagnostic of diabetes?
> 48mmol/l
In the diagnosis of diabetes, if a patient has symptoms, how many diagnostic lab glucose reading must they have before a diagnosis is made?
1
In the diagnosis of diabetes, if a patient does not have any symptoms, how many diagnostic lab glucose reading must they have before a diagnosis is made?
2
What is the name given to the stage before diabetes, sometimes known as pre-diabetes?
Intermediate hyperglycaemia
What fasting glucose levels are indicative of intermediate hyperglycaemia/pre-diabetes?
6.1-7mmol/l
What HbA1c levels are indicative of intermediate hyperglycaemia/pre-diabetes?
42-47mmol/l
HbA1c?
Glucose bound to haemoglobin, an irreversible process. This blood test measures the levels of glucose bound to haemoglobin in the blood
What are the advantages of using a HbA1c test compared to fasting BG?
HbA1c can be taken immediately, no fasting required
List some of times in which HbA1c cannot be used for the diagnosis of diabetes mellitus.
-All children and young people
-Pregnancy
-Renal failure
-HIV infection
-Patients at high risk of diabetes who are acutely ill
-Patients on meds which can cause glucose spikes
What is more common- type 1 or type 2 diabetes?
Type 2
->if you got this wrong girl pls just drop out already x
What are some key points in history which help to determine which type of diabetes someone has?
-Age at diagnosis
-FH of diabetes
-Personal or familial history of autoimmune conditions
-Any hyperglycaemic symptoms
Which type of diabetes is an autoimmune condition?
Type 1 diabetes
What are some of the things you would examine or investigate to determine the type of a diabetes a patient has?
BMI
Ketones
Any sings of complications e.g. foot examination and retinal screening
Which cells are destroyed via autoimmune destruction in type 1 diabetes?
Islet cells - the insulin producing cells in the pancreas
Which auto antibodies can be measured and trigger the destruction of the insulin producing beta cells?
GAD antibodies- IAA, IA-2A, ZnT8
What is type 1 diabetes characterised by?
Insulin deficiency
What affect does this insulin deficiency have on the
- adipose tissue
-muscle
-liver
Adipose- increase lipolysis
Muscle- reduced glucose uptake
Liver- raised glucose production
In type 1 diabetes, the body cannot use glucose as it’s normal source of energy to breakdown muscle and fat. What does this result in?
Ketones
If type 1 diabetes is left untreated, what could develop?
Diabetic ketoacidosis (DKA)
Who is type 1 diabetes more common in?
Children and younger adults
In which type of diabetes is there a genetic link?
Both
Type 2 diabetes is a lot more inheritable…this contradicts another lecture but I would probs listen to this one
What does the development of type 1 diabetes mellitus require?
Genetic predisposition
AND
Trigger e.g. viral infection
What are some of the symptoms of type 1 diabetes?
Polydipsia
Polyuria/nocturia
Tiredness
Weight loss
Blurred vision
Abdominal pain
What are some of the signs upon examination of type 1 diabetes?
Ketones on breath
Dehydration
May have increased RR, tachycardia, hypotension
Low grade infections e.g. thrush
What can ketones on breath smell like?
Pear drops
C-peptide levels can be used to confirm diagnosis of type 1 diabetes but is only reliable after 3yrs of diagnosis. What would the C-peptide levels be expected to be like at this point?
Undetectable
Low levels would suggest more recently diagnosed
What happens in type 2 diabetes?
Increased cellular insulin resistance
Initially if you have insulin resistance, how does the body try to compromise?
By producing more insulin
->this keeps insulin levels fairly steady for a period of time but eventually almost ‘burns out’ as body cannot keep producing so much insulin over a longer period of time
Why is type 2 diabetes more common now?
-People heavier weight
-Ageing population and more common as we get older
-More sedentary lifestyle
What are some of the symptoms of type 2 diabetes?
Polydipsia
Polyuria/nocturia
Tiredness
Sometimes weight loss but less common
Blurred vision
What are some of the signs of type 2 diabetes?
Not ketotic
Usually overweight
Low grade infections e.g. thrush
Microvascular/macrovascular complications at diagnosis
List some of the risk factors for type 2 diabetes.
Overweight
Family history
Older age
Previous history of gestational diabetes
Inactive life style
Previously high blood glucose
What is a recognised genetic syndrome which can cause diabetes mellitus?
MODY- monogenic diabetes
Gestational diabetes?
Diabetes during pregnancy
Wat is MODY?
Autosomal dominant condition meaning there is impaired beta-cell function
What is a key factor of a history that would point to MODY?
Family history of many family members having diabetes
What happens in those with a glucokinase mutation?
Glucose levels from birth are always slightly higher
What is the treatment for monogenic diabetes cause by a glucokinase mutation?
Diet treatment
What is secondary diabetes mellitus?
Diabetes as a result of medications e.g. steroid use, pancreatic destruction, genetic syndromes, endocrine disorders
Which endocrine disorders can cause secondary diabetes?
Cushing’s syndrome
Acromegaly
Pheochromocytoma
What other condition can cause destruction of the pancreas and can cause secondary diabetes?
Haemochromatosis- excess iron deposition
Cystic fibrosis
Chronic pancreatitis
Pancreatectomy
In which trimesters does gestational diabetes occur?
2nd-3rd
Which neonatal problems can occur as a result of gestational diabetes?
Macrosomia
Respiratory distress
Neonatal hypoglycaemia
