MBBS 1st Yr. Practical
Dr. U.S. Khoo
October 23, 2002 - 10:45 AM
INTRODUCTION TO HEALTH AND DISEASE BLOCK
CELL INJURY AND CELL DEATH
G1 Kidney - coagulative necrosis (Infarct)
A piece of normal kidney (N2) is included for comparison. Please note the
morphology of normal glomerulus, renal tubules and blood vessels.
A. Note: - Necrotic tissue: architecture preserved
- Necrotic cells:
nuclei: faded & disappeared (karyolysis)
- Compare with viable portion of kidney included in slide.
B. Questions: How would you describe the demarcation between the viable and
necrotic area? Is there any reaction?
G2 Lymph node: Caseous necrosis
A section of normal lymph node (N1) is included for comparison. Lymp hoid follicles,
paracortical zone and sinuses are present.
A. Note: - part of lymph node preserved, but abnormal
- necrotic area:
eosinophilic, amorphous, granular material
lacking cell outline. (Caseous = cheese- like)
B. Question: Can you find the differences between the necrotic lesions illustrated
in slide 1 and 2?
G3 Brain: Colliquative necrosis
A section of normal brain (N5) is included for comparison. Glial cells are surrounded
by fibrillary glial substance.
A. Note: - loss of normal brain tissue
- replaced by macrophages and cell debris
- space created (fluid filled)
B. Questions: Why is this type of necrosis common in the brain?
What is the origin of the pigment inside some of the macrophages?
G5 Liver - Fatty Degeneration
A section of normal liver (N3) is included. Preserved lobular architecture, portal tracts
and central veins can be identified.
A. Note: - Large intracytoplasmic space in liver cells - fat vacuole, with nuclei
pushed to one side
B. Question: What are the mechanisms that give rise to fatty change?
S56 Lymph node - Malignant lymphoma, Burkitt's type
Apoptosis (Demonstration only)
A. Note: - Loss of normal architecture and replacement of sheets of
monomorphic tumour cells.
- Scattered cells showing shrinkage and condensation of cytoplasm
and nucleus. Such cells have eosinophilic cytoplasm and pyknotic
B. Question: What does frequent apoptotic bodies indicate in this tumour?