What is Diabetes Mellitus?

Question 1

What are some symptoms of hyperglycaemia?

Answer 1

• Polydipsia (excessive thirst)
• Polyuria (abnormally large urine production)
• Blurred vision
• Weight Loss
• Infections

Question 2

Long term microvascular complications of hyperglycaemia?

Answer 2

• Retinopathy
• Neuropathy
• Nephropathy

Question 3

Long term macrovascular complications of hyperglycaemia?

Answer 3

• Stroke
• MI
• Peripheral vascular disease

Question 4

What are the normal fasting, random and 2 hour post oral glucose tolerance test blood glucose values?

Answer 4

Normal fasting: < 7 mM

Normal Random: < 11 mM

Normal 2 hour OGTT: < 11 (normal: < 7, Intermediate: 7.8-11)

Question 5

When diagnosing diabetes based on symptoms and tests, how many rounds of glucose tests are needed to diagnose?

Answer 5

• Typical symptoms + 1 diagnostic test
  OR
• 2 diagnostic tests (or 1 plus HbA1c)

Question 6

Diagnostic tests for diabetes?

Answer 6

• Finger prick for hyperglycaemia (not necessarily diabetes)
• Oral glucose tolerance test (OGTT)
• HbA1c

Question 7

What HbA1c value suggests diabetes?

Answer 7

> 48 mmol/mol

Question 8

Fasting and 2 hour post OGTT glucose levels that suggest intermediate hyperglycaemia? HbA1c levels?

Answer 8

• Fasting: 6.1 - 7 mmol/L
• 2hr post OGTT: 7.8 - 11 mmol/L
• HbA1c 42 - 47 mmol/mol

Question 9

What does identification of intermediate hyperglycaemia mean for the patient?

Answer 9

• Increased chance of future diabetes

- Increased chance of CVS disorders

Question 10

What is HbA1c? What leads to elevated HbA1c levels?

Answer 10

• It is glycosylated haemoglobin, glucose in the blood binds haemoglobin at a specific site forming HbA1c
• Hyperglycaemia, the more glucose in the blood the more HbA1c

Question 11

How long does HbA1c circulate for? Why is this useful clinically?

Answer 11

• For the lifespan of the RBC
• Means raised HbA1c “reflects the prevailing blood glucose levels from the preceding 2-3 months”
• Glycosylation of RBC’s only occurs when blood glucose is raised consistently for a while, reflects the climate not the weather

Question 12

When can HbA1c values be misleading for diabetes diagnosis?

Answer 12

• Renal failure
• Hemoglobinopathies
• Anaemia

Question 13

When can HbA1c not be used to diagnose diabetes?

Answer 13

• Children and young people
• Pregnancy (current or within 2 months)
• Acutely ill patients at risk of diabetes
• Patients taking medication that may cause rapid glucose rise (corticosteroids / antipsychotic drugs)
• Patients with acute pancreatic damage
• Patients with renal failure
• Patients with HIV

Question 14

Out of the diabetic community, how common are type 1 & 2 diabetes? (what percentage of diabetics has each type)

Answer 14

• 88% Type 2
• 11% Type 1
• 1% Other types of diabetes

Question 15

How do type 1 and type 2 diabetes vary across age groups?

Answer 15

• Type 1: Evenly spread across age groups, more young people with the condition
• Type 2: Much more common in older individuals

Question 16

If your father has type 1 diabetes how likely are you to get the condition? Mother? Sibling? Twin?

Answer 16

Father - 6% chance you inherit diabetes

Mother - 1%

Sibling - 8%

Twin - 30-50%

Question 17

Are you born with type 1 diabetes or is it something you develop?

Answer 17

• Genetic predisposition + Trigger (viral infection?)

- Not 100% sure about this. One website said peak diagnosis age of type 1 in the USA is 14 years old

Question 18

Symptoms of type 1 diabetes mellitus?

Answer 18

• Thirst
• Tiredness
• Polyuria / nocturia
• Weight loss
• Blurred vision
• Abdominal pain

Question 19

Signs on clinical examination of type 1 diabetes mellitus?

Answer 19

• Ketones on breath
• Dehydration
• Increased RR, HR & hypotension
• Low grade infections (thrush / balanitis)

Question 20

How was diabetes tested for prior to blood testing?

Answer 20

• Urine testing
• Two test tubes, one with urine the other with blue Fehling’s solution. Heat them both and combine, if it stays blue no sugar, yellow is some sugar, orange is lots of sugar

Question 21

Describe the amino acid structure of insulin

Answer 21

• An Alpha chain of 21 AA’s, a beta chain of 30 AA’s and disulphide bonds linking the two together

Question 22

If one of your parents has type 2 diabetes how likely are you to get the condition? Both parents? Identical twin? Sibling?

Answer 22

• One parent: 15%
• Both parents: 75%
• Identical twin: 90-100%
• Sibling: 10%

Question 23

Signs of type 2 diabetes?

Answer 23

• Many have no symptoms
• Thirst, tiredness, polyuria, blurred vision, sometimes weight loss
• Often overweight
• Micro / macro - vascular complications

Question 24

Which ethnicities are more likely to develop diabetes?

Answer 24

• Black Africans
• Chinese
• South Asian
• African-Caribbean

Question 25

List some conditions that increase the risk of type 2 diabetes

Answer 25

• CVS disease
• Hypertension
• Obesity
• Stroke
• Polycystic ovarian syndrome
• History of gestational diabetes
• Mental health problems

Question 26

What is MODY? Pathophysiology?

Which genes can be mutated in MODY?

Answer 26

• Maturity Onset Diabetes in the Young
• Single gene defect in beta-cells, autosomal dominant
• Glucokinase mutations OR Transcription Factor Mutations

Question 27

What is gestational diabetes? What are the risk factors for it?

Answer 27

• Increased insulin resistance during pregnancy resulting in hyperglycaemia, usually disappears after childbirth
• Risk factors include being overweight / inactive & a FH of type 2 diabetes
• Leads to higher chance of type 2 diabetes later in life

Question 28

What are some neonatal problems associated with gestational diabetes?

Answer 28

• Macrosomia (baby is large when born)
• Respiratory distress
• Neonatal hypoglycaemia

Question 29

What are some causes of secondary diabetes?

Answer 29

• Major disease of exocrine pancreas (chronic pancreatitis / Haemochromatosis / CF)
• Endocrinopathies (acromegaly / Cushing’s / Glucagonoma / phaeochromocytoma)
• Steroids