Endocrinology

Question 1

What is Type 1 Diabetes?

Answer 1

Autoimmune destruction of pancreatic beta cells leading to complete insulin deficiency.

Question 2

Risk Factors of T1DM?

Answer 2

• > Family history of HLA DR3-DQ2 or HLA DR4-DQ8
• > Northern European
• > Autoimmune diseases – 90%

Question 3

Pathophysiology of T1DM?

Answer 3

Autoantibodies attack beta cells in the Islets of Langerhans -> Insulin deficiency -> Hyperglycemia.
Continuous breakdown of glycogen from liver (gluconeogenesis) -> Glycosuria

Question 4

Signs and Symptoms of T1DM?

Answer 4

Classic Triad: Polydipsia, Polyuria, Weight- loss [BMI < 25]
Usually a short history of severe symptoms
May also present with ketosis

Question 5

Diagnosis of T1DM?

Answer 5

-> Random Plasma Glucose > 11mmol/L

Question 6

Treatment of T1DM?

Answer 6

> Insulin
Short - acting insulins and insulin analogues (4-6 hrs)
Longer - acting insulin (12-24 hrs)
**Typical patient presenting with NEW Type 1 DM:
Polydipsia, Polyuria, Ketosis, Rapid weight- loss, Young, BMI <25, personal/ family history of autoimmune disease. **

Question 7

What is Type 2 Diabetes?

Answer 7

=> Non – insulin dependent
Patients gradually become insulin resistant/ pancreatic beta cells fail to secrete enough insulin or BOTH.
Progresses from impaired glucose tolerance.

Question 8

Causes of T2DM?

Answer 8

• Reduced insulin secretion, +/- increased insulin resistance.
• Others: Gestational Diabetes, Steroids, Cushing’s, Chronic pancreatitis.

Question 9

Risk factors of T2DM?

Answer 9

• > Lifestyle factors: Obesity, Lack of exercise, Calorie and Alcohol excess
• > Higher prevalence in Asian men
• > Above 40 yrs age – later onset
• > Hypertension

Question 10

Signs and Symptoms of T2DM?

Answer 10

Polydipsia 
Polyuria 
Glycosuria 
Central obesity 
Slower onset 
Blurred vision

Question 11

Investigations of T2DM?

Answer 11

• > Fasting plasma glucose: more than 7 mmol/L
• > Random Plasma Glucose: more than 11 mmol/L
• > HbA1c more than 48 mmol/L

Question 12

Treatment of T2DM?

Answer 12

1st Line = Lifestyle Changes
> Dietary advice: High in complex carbs. Low in fat
> Smoking cessation
> Decrease alcohol intake
> Exercise
> Regular blood glucose and HbA1c monitoring
2nd Line = Medications
> Metformin (biguanide): Increases insulin sensitivity – first choice in overweight patients
> If HbA1c remains high then DUAL Therapy with Metformin:
+ DPP4 inhibitor
+ Sulphonylurea (gliclazide) - Increases insulin secretion
+ Pioglitazone
> If still high = TRIPLE Therapy
> Then Insulin

Question 13

What is Diabetic Ketoacidosis?

Answer 13

=> Complete lack of insulin results in high ketone production.

Question 14

Aetiology of DKA

Answer 14

Untreated or undiagnosed T1DM

Infection/illness

Question 15

Pathophysiology of DKA

Answer 15

Absence of insulin -> uncontrolled catabolism -> unrestrained gluconeogenesis and decreased peripheral glucose uptake -> Hyperglycaemia.

Hyperglycaemia -> Osmotic diuresis -> Dehydration

Peripheral lipolysis for energy -> Increase in circulating free fatty acids -> oxidised to Acetyl CoA -> Ketone bodies(acidic) = ACIDOSIS

Question 16

Symptoms of DKA

Answer 16

Extreme diabetes symptoms plus:
	• Nausea + Vomiting
	• Weight Loss
	• Confusion and reduced mental state
	• Lethargy
	• Abdominal pain

Question 17

Signs of DKA

Answer 17

• Kussmaul’s breathing [rapid slow]
  
  • ‘Pear drop’ breath [due to ketones]
  • Hypotension
  • Tachycardia

Question 18

Investigation of DKA

Answer 18

• > Random Plasma Glucose > 11mmol/L
• > Plasma ketone > 3mmol/L
• > Blood pH < 7.35 or Bicarb < 15mmol/L
• > Urine dipstick: Glycosuria, Ketonuria
• > Serum U+E: -Raised urea + creatinine. -Decreased Total K+, Increased serum K+.

Question 19

Treatment of DKA

Answer 19

1. ABC management
   
   2. Replace fluid – 0.9% saline IV
   3. IV insulin
   4. Restore electrolytes – e.g. K+

Question 20

What is Hyperosmolar Hyperglycaemic State (HHS):

Answer 20

=> Marked hyperglycaemia, Hyperosmolality, Mild/ no ketosis

Medical Emergency – Serious complication of T2DM.

Question 21

Aetiology of HHS

Answer 21

• Untreated or undiagnosed T2DM

- Infection/illness