CBL - Diabetes

Question 1

A diagnosis of diabetes is given under what criteria? [5]

Answer 1

1. in the presence of symptoms:
   
   • polyurea,
   • polydipsia,
   • weight loss
2. Random plasma glucose >11.1 mmol/l
3. Fasting plasma glucose >7.0 mmol/l
4. 2hr post 75g OGT >11.1
5. If no symptoms, results require to be repeated again to confirm diagnosis

Question 2

In which situations would a measurement of HbA1C alone be inappropriate for diagnosing diabetes and why? [5]

Answer 2

1. Children/young adults (more likely to have Type 1 which typically has rapid onset)
2. Recent use of medication likely to increase plasma glucose acutely
3. Acute pancreatic damage
4. Acutely illness (could be stress hyperglycaemia)
5. A patient whose symptoms have been present for <2months (HbA1C reflects glycated Hb over many weeks so it “lags behind”)

Question 3

What are the clinical features of Type 2 diabetes? [6]

Answer 3

1. Usually occurs in over 40’s
2. Most common type of diabetes
3. Gradual onset
4. Often few or absent symptoms
5. Typically overweight or obese with features of insulin resistance
6. Family history of diabetes is common

Question 4

State the differential diagnoses for Type 2 diabetes [4]

Answer 4

1. LADA (latent autoimmune diabetes in adults)
2. Pancreatic diabetes
3. Secondary diabetes
4. Genetic diabetes/MODY

Question 5

What are the clinical features of latent autoimmune diabetes in adults (LADA)? [5]

Answer 5

1. usually more prominent osmotic features although often not insulin requiring for few years post-diagnosis
2. obesity is not a predisposing factor but presence of obesity does not exclude LADA
3. may have other autoimmune history or family history
4. auto-antibodies (GAD/Islet cell) often present
5. can initially be difficult to distinguish from T2DM - often need to observe over time.

Question 6

What are the clinical features of pancreatic diabetes? [3]

Answer 6

1. history of alcohol excess (abnormal LFTs may be due to alcohol) may predispose to pancreatic pathology however no history of acute pancreatitis
2. history of exocrine dysfunction would suggest pancreatic pathology (diarrhoea, malabsorption)
3. haemochromatosis: iron deposition can affect a number of organs including:
   
   • pancreas (diabetes)
   • liver (abnormal LFTs)
   • heart (cardiomyopathy)

Question 7

What endocrinopathies can cause secondary diabetes? [3]

Answer 7

1. Acromegaly
2. Cushing’s syndrome
3. Thyrotoxicosis

Question 8

What are the clinical features of genetic diabetes/MODY? [3]

Answer 8

1. family history is present however, only one parent known to be affected, not multigenerational
2. Typically aged <25 at diagnosis
3. Other clinical features that may suggest genetic diabetes is more likely absent e.g.
   
   • renal disease (HN1B)
   • personal or family history of deafness (maternally inherited diabetes and deafness, MIDD)
   • sensitivity to sulphonylureas, HNF1A patients often experience hypoglycaemia with standard doses of gliclazide and smaller doses are often effective

Question 9

What investigations should you carry out on a patient with T2DM (after testing glucose)? [9]

Answer 9

1. Exclude ketoacidosis
   
   • Capillary ketone testing
   • Urine ketone testing
   • Serum bicarbonate
   • (T2DM not usually associated with ketoacidosis but it is a metabolic emergency requiring immediate lifesaving treatment)
2. In some patients consider:
   
   • Auto-antibodies
     
     • tend to be negative in T2DM
   • C-Peptide (after 6 months and in context of glucose >5)
     
     • usually elevated in early T2DM
     • later in natural history approx. (>10yrs) of T2DM some patients become insulin deficient.
3. Further investigation of abnormal LFTs
   
   • could be non-alcoholic steatohepatitis associated with diabetes and insulin resistance
   • could be haemachromatosis (which also causes diabetes)
     
     • check ferritin, FBC
   • could be alcohol related (possible increasing likelihood of secondary (pancreatic) diabetes)
     
     • faecal elastase for assessment of pancreatic exocrine function

Question 10

What lifestyle changes are recommended for patients with type 2 diabetes mellitus? [3]

Answer 10

1. Diet including advice on weight loss and healthy carbohydrate intake
2. Exercise - increase in activity level should be encouraged, exercise improves insulin sensitivity and cardiovascular risk factors
3. Smoking cessation

Question 11

What are the pharmacological treatment options for type 2 diabetes? [7]

Answer 11

1. Biguanide
   
   • e.g. metformin
2. Sulphonylureas
   
   • e.g. gliclazide
3. DPP4 inhibitor
   
   • e.g. alogliptin
4. GLP1 antagonist
   
   • e.g. liraglutide
5. SGLT2 inhibitor
   
   • e.g. empagliflozin
6. Insulin
   
   • e.g. humulin I (intermediate acting)
   • e.g. humulin M3 (biphasic)
7. Antihypertensives
   
   • especially ACE inhibitor in presence of diabetic nephropathy

Question 12

What are the target diastolic BP and target systolic BP in patients with diabetes? [2]

Answer 12

1. target diastolic BP ≤80 mmHg
2. target systolic BP ≤130 mmHg

Question 13

Patients with diabetes requiring antihypertensive treatment should be commenced on? [3]

Answer 13

1. an ACE inhibitor (ARB if ACE inhibitor intolerant), or
2. a calcium channel blocker, or
3. a thiazide diuretic

Question 14

What drugs are used to lower cholesterol levels in T2DM and what is the target cholesterol level after treatment? [2]

Answer 14

1. statins are used (simvastatin 40 mg or atorvastatin 10 mg)
2. target cholesterol should be <5

Question 15

What are the symptoms of hypoglycaemia? [6]

Answer 15

1. tremor,
2. sweating,
3. palpitations,
4. blurred vision,
5. confusion,
6. drowsiness

Question 16

How do you treat hypoglycaemia? [2]

Answer 16

1. 15-20g fast acting carbohydrate
   
   • e.g. 5-6 dextrose tabs
2. recheck blood glucose 15-20 mins later

Question 17

Describe the biphasic mixed insulin regime [6]

Answer 17

1. Given twice per day.
2. Short acting component in the morning covers breakfast and lunch.
3. Short acting component in the evening covers evening meal and snack before bed.
4. Long acting component of both insulins cover basal insulin requirements.
5. Mealtimes should be at relatively fixed times in order to minimise hypoglycemia and coincide with peak action of short acting insulin.
6. Dose does not vary and while easier to administer, more difficult to achieve optimal glycaemic control without hypoglycaemia.

Question 18

Describe the basal bolus insulin regimen [6]

Answer 18

1. Given at least 4 times per day.
2. Basal (long acting) insulin is given once or sometimes twice per day depending on the formulation.
3. Bolus doses of fast acting insulin are given with carbohydrate containing meals.
4. If patients are not eating carbohydrate, bolus doses are not given.
5. If snacks containing significant doses of carbohydrate are taken, patients should take additional bolus insulin.
6. This regime gives greater flexibility regarding mealtimes and carbohydrate ingestion but does require additional input from patient (multiple injections, multiple blood glucose testing)