Overview

• Also called insulin-dependent diabetes mellitus (IDDM).
• Formerly known as juvenile diabetes due to early onset, typically during childhood.
• Less common than Type II, accounting for about 10% of diabetes cases.
• Usually more severe because of acute complications if blood glucose is not well-controlled.

Causes

• Autoimmune destruction of pancreatic beta cells.
• Leads to little or no insulin production.
• Often triggered by possible factors:
  • Viral exposures: Epstein-Barr virus, cytomegalovirus, mumps.
  • Genetics: Runs in families.
  • Geographic factors: Higher prevalence away from the equator, e.g., Finland.

Typical Onset

• Rapid development in children.
• Can occur in adults as a latent autoimmune diabetes variant.

Signs and Symptoms

• Increased thirst (polydipsia)
• Increased hunger (polyphagia)
• Increased urine volume (polyuria)
• Fatigue
• Blurred vision
• Slowed healing of wounds

Diagnosis

• Glycated hemoglobin (A1c) test
  • Measures the percentage of hemoglobin with blood sugar attached.
  • Reflects blood glucose control over 2-3 months.
  • Levels above 6.5% suggest diabetes.
• Random blood sugar test
  • Blood sample taken randomly, regardless of fasting.
  • Blood glucose above 110 mg/dL indicates abnormality.
• Fasting blood sugar test
  • Fasting for 12 hours before testing.
  • Normal: <100 mg/dL.
  • Diabetic: >125 mg/dL.

Treatments

• Insulin injections are essential.
• No known preventive cause or cure; management focuses on blood sugar control.
  • Note:  Pancreatic transplants are challenging, and are not curative as the underlying cause of autoimmune destruction of the pancreatic beta cells by WBCs still exists.

Risk Factors

• Possible viral triggers.
• Geographic location (e.g., higher rates farther from the equator).
• Family history.
• Not linked to obesity (unlike Type II).

Complications of Uncontrolled Diabetes

• Cardiovascular disease: Stroke, heart attack, peripheral vascular disease.
• Blood vessel damage leads to:
  • Atheromas formation.
  • Vascular damage affecting organs.
• Kidney failure (due to nephropathy).
• Eye damage: Leading to blindness (diabetic retinopathy).
• Nerve damage: Neuropathy.
• Pregnancy complications: Stillbirths and miscarriages.
• Increased risk of amputations due to ischemia and gangrene.

Summary

• Autoimmune origin causes destruction of beta cells.
• Rapid onset in children, generally non-obese.
• Requires lifelong insulin therapy.
• Precursors and triggers are still under study.
• The condition leads to vascular damage affecting multiple organs and systems, emphasizing the importance of tight blood glucose control.