Subtitle: A complete, exam-oriented review of necrosis based on Robbins and high-yield pathology concepts.

Author: PathologyMCQ Team
Category: General Pathology
Read Time: 6 minutes

At a Glance

• Understand the mechanisms of irreversible injury and necrosis
• Learn Robbins-based differences between all necrosis types
• Includes 11 MCQs + practice quiz
• Ideal for FRCPath, NEET-SS, INICET, PG exams

Difficulty: Moderate

Contents

1. Contents
2. Introduction
3. What Is Necrosis?
4. Mechanism of Irreversible Cell Injury
5. Types of Necrosis
6. Morphology: Robbins High-Yield Features
7. MCQ Section
8. Key Takeaways
9. References

1. Introduction

Necrosis is a hallmark of irreversible cell injury, resulting in uncontrolled cell death, enzymatic degradation and inflammation.
Different tissues display distinct necrosis patterns, making this topic highly testable across competitive exams.
This review covers mechanisms, morphological features and exam-focused MCQs based on Robbins.

2. What Is Necrosis?

Necrosis is pathological cell death characterised by:

• breakdown of cell membranes
• enzyme leakage
• inflammatory response
• loss of nuclear detail

Unlike apoptosis, necrosis is always pathological.

3. Mechanism of Irreversible Cell Injury

Irreversible injury occurs due to:

• Critical ATP depletion
• Loss of mitochondrial function
• Calcium influx → enzyme activation
• Membrane damage
• Lysosomal rupture
• Inflammatory cell infiltration

Loss of membrane integrity is the decisive point of no return.

4. Types of Necrosis

Coagulative Necrosis

• Tissue architecture preserved
• Seen in infarcts of solid organs
• Example: myocardial infarction

Liquefactive Necrosis

• Complete enzymatic digestion
• Characteristic of brain infarction
• Also seen in bacterial abscesses

Caseous Necrosis

• “Cheese-like” appearance
• Classic for tuberculosis granulomas
• Occurs in many organs except the brain

Fat Necrosis

• Seen in acute pancreatitis
• Chalky white deposits due to calcium binding (saponification)

Fibrinoid Necrosis

• Immune-mediated vascular damage
• Seen in autoimmune vasculitis and severe hypertension

5. Morphology: Robbins High-Yield Features

On H&E staining:

• Cytoplasmic eosinophilia increases
• Nuclei show pyknosis, karyorrhexis, or karyolysis
• Cell outlines become blurred
• Enzyme leakage causes local inflammation

These features help distinguish necrosis from apoptosis.

6.High – Yield MCQS

7. Key Takeaways

• Necrosis is always pathological
• Liquefactive necrosis is typical of the brain
• Caseous necrosis is characteristic of TB granulomas
• Loss of membrane integrity marks irreversible injury
• Necrotic cells show bright pink eosinophilic cytoplasm

8. References

1. Robbins & Cotran Pathologic Basis of Disease, 10th Edition
2. WHO Classification of Tumours
3. Modern Pathology – Cell Injury Reviews

9.Recommended Learning