CSIM 1.84: Multisystem disease

Question 1

What is diabetic ketoacidosis?

Answer 1

• The lack of insulin and corresponding elevation of glucagon leads to increased release of glucose by the liver
  
  • The absence of insulin also leads to the release of free fatty acids from adipose tissue (lipolysis), which are converted through a process called beta oxidation, again in the liver, into ketone bodies
  • Meanwhile, the predominance of stress hormones, such as glucagon, corticosteroids and catecholamines cause gluconeogenesis and ketogenesis

This results in hyperglycaemic, acidic blood

Question 2

What are the causes and types of diabetes mellitus?

Answer 2

• Type 1 - absolute insulin deficiency
  
  • Type 2 - resistance + slight deficiency of insulin
  • Chronic pancreatitis or Pancreatectomy
  • Endocrine disease (acromegaly, Cushing’s syndrome, glucagonoma)
  • Drugs (glucocorticoids)
  • Gestational diabetes

Question 3

Describe the factors which can contribute to likelihood of getting type 1 diabetes

Answer 3

Genetic susceptibility:
• Class 2 MHC alleles

Environmental factors
• Coxsackie virus

Question 4

Describe the pathogenesis of type 2 diabetes

Answer 4

• Genetic and environmental (obesity) factors contribute to an insulin resistance
  
  • Compensatory Beta-cell hyperplasia occurs in the Islets of Langerhans
  • This compensatory mechanism works temporarily and then can fail leading to diabetic symptoms

Question 5

What is metabolic syndrome?

Answer 5

Metabolic abnormalities which convey an increased risk of cardiovascular disease:

It is central obesity plus two from:
  •  Raised triglycerides
  •  Reduced HDL
  •  Hypertension
  •  Raised fasting glucose

Affects 20% of the world’s population

Question 6

What type of coma does each type of diabetes have as a complication?

Answer 6

Type 1 - ketoacidotic coma

Type 2 - hyperosmolar non-ketotic coma

Question 7

What are the complications of diabetes?

Answer 7

• Diabetic retinopathy
  
  • Renal failure
  • Neuropathy (patients dont notice cuts or blisters PARTICULARLY ON FEET, so they develop and become infects)
  • Atheroma (CHD, CVD)

Question 8

What causes the complications of diabetes?

Answer 8

Hyperglycaemia leads to advanced glycation end products

These form due to reactions between glucose metabolites and amino groups of proteins found in the body

This results in:
• Reduced elasticity
• Protein trapping
• Thickening of capillary basement membranes

Question 9

What are the most common causes of death in diabetes?

Answer 9

renal and cardiovascular diseases