Necrosis | Anatomy2Medicine
Necrosis

Necrosis

    • Irreversible Injury
    • irreversible Cell death presents as

 

  • necrosis

 

      • apoptosis

 

  • Necrosis
  • Fundamentally is  a cytoplasmic driven process.

 

      • It is a pathologic process resulting from the swelling and denaturation of the cell
      • hypoxia leads to depleted ATP reserves and opening of ion channels
      • leads to cellular swelling and enzyme release from digestive lysozymes
      • temporal sequence observed after necrotic cell death
        • Hours after the insult there are no clear features.
        • 1 day after there are microscopic changes (waviness).
        • 1–3 days after there is gross necrosis and a microscopic infiltration by neutrophils
        • 3–7 days after there is disintegration of the dead tissue and accumulation of macrophages.
        • 1–2 weeks after there is granulation tissue (fibroblast and blood vessel proliferation).
        • 2–8 weeks after there is increasing collagen deposition
        • 2 months after there is a dense fibrous scar.(MCQ)
      • Liquefactive necrosis affects soft organs
        • brain infarction from stroke(MCQ)
      • Hemorrhagic necrosis affects highly vascular organs
        • pulmonary infarction from embolism(MCQ)

 

  • Caseous necrosis

 

        • cheesy white center of granulomas (eg, tuberculosis). (MCQ)

 

  • Fat necrosis – Occurs dead adipose tissue

 

      • trauma to breast(MCQ)
      • enzyme release in pancreatitis(MCQ)
    • Areas of necrosis may calcify as in breast microcalcifications associated with necrosis from fibrocystic change or carcinoma) (MCQ)

Distinguishing necrosis from apoptosis. (MCQ)

Necrosis