Lecture on Diabetic Ketoacidosis (DKA)

Introduction to Diabetes Mellitus

• Diabetes mellitus is often seen as a chronic disease.
• Untreated, it can lead to serious complications over time.
• Focus on acute complications: Diabetic Ketoacidosis (DKA).
• DKA is potentially life-threatening and occurs mainly in Type 1 diabetes.

Type 1 Diabetes Overview

• Autoimmune destruction of beta cells in the pancreas.
• Results in absolute insulin deficiency.

Insulin and Energy Balance

• Insulin requirements are a balancing act with energy needs.
• Insulin helps transfer glucose from blood into cells for energy.
• Individuals with Type 1 diabetes lack sufficient insulin production.

Acute Stress and DKA

• Day-to-day activities might not be problematic.
• Stress (e.g., infection) increases energy needs dramatically.
• Inadequate insulin causes imbalance: the body can't compensate.
• The body goes into a 'starvation state'—glucose present but unusable.

Starvation Metabolism

• Purpose: Preserve energy for crucial organs, mainly the brain.
• Brain's energy sources: glucose and ketones (prefers glucose).
• Starvation metabolism: Converts fat, protein, glycogen into glucose/ketones.

Key Metabolic Pathways

1. Proteolysis
   • Breakdown of proteins into amino acids.
   • Amino acids transported to liver for gluconeogenesis.
2. Lipolysis
   • Breakdown of lipids (fats) into glycerol and free fatty acids.
   • Also produces inflammatory cytokines.
3. Gluconeogenesis
   • Creation of glucose from amino acids, glycerol, and free fatty acids.
   • By-product: acetyl CoA used in ketogenesis.
4. Ketogenesis
   • Creation of ketones (alternative energy source).
   • Uses acetyl CoA from gluconeogenesis.
5. Glycogenolysis
   • Breakdown of glycogen into glucose.
   • Glycogen is a storage form of glucose.

Clinical Presentation of DKA

• Rapid onset: Hours to days.
• Symptoms: Abdominal pain, nausea, vomiting, severe dehydration, altered mental status (confusion, unconsciousness).

Underlying Causes of Symptoms

• Nausea, Vomiting, Abdominal Pain
  • Caused by inflammatory cytokines irritating the digestive tract.
• Severe Dehydration
  • Vomiting depletes fluids.
  • Hyperglycemia leads to glucose spilling into urine (glucosuria).
  • Osmotic diuresis: Water follows glucose into urine, causing fluid loss.
• Altered Mental Status
  • Dehydration and acidosis worsen mental status.
  • Ketones lower blood pH (acidosis), leading to metabolic acidosis.
  • Severe acidosis can cause cardiac arrhythmias.

Conclusion

• DKA is connected to metabolic imbalances in Type 1 diabetes.
• Key symptoms: Abdominal pain, altered mental status, dehydration.
• Requires quick and aggressive treatment (IV fluids, insulin).
• DKA can be fatal if untreated.