LIQUEFACTIVE NECROSIS AND CASEOUS NECROSIS

1. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
DEPARTMENT OF VETERINARY VETERINARY
PATHOLOGY MSc PROGRAM
Assignment Of General Veterinary Pathology
TITLE : LIQUEFACTIVE NECROSIS AND
CASEOUS NECROSIS
Submitted to:- Dr. Mo’a melaku (DVM, MVSc and Assist.
Professor of Veterinary Pathology)
Prepared by: Abera Bayisa
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2. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
INTRODUCTION
• Necrosis as a form of cell death is almost always associated with
a pathological process. When cells die by necrosis, they exhibit
two major types of microscopes or macroscopic appearance..
• Different types of necrosis are recognized according to the
causes, pathogenesis and the tissue involved.
• These include
Coagulative,
 LIQUEFACTIVE,
 CASEOUS and
Gangranous necrosis .
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3. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Liquefactive necrosis
• Definition: necrosis with complete loss of cell and
tissue structure.
• liquefactive necrosis forms a viscous liquid mass as
the dead cells are being digested.
• It is a characteristic of focal bacterial or,
occasionally, fungal infections, because microbes
stimulate the accumulation of inflammatory cells.
• Ischemic (hypoxic) cell death in the brain/ central
nervous system
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4. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
• The major causes of liquefactive necrosis are:
 In all solid organs of the body:
• Infectious agents (bacteria, fungi, viruses, parasites)
 In the brain
• Due to excitotoxicity, hypoxic death of cells within the central
nervous system can result in liquefactive necrosis.
• Brain cells have a large amount of digestive enzymes
(hydrolases). These enzymes cause the neural tissue to become
soft and liquefy
 In the lung
• when there is an abscess with lots of acute inflammatory cells
whose release of proteolytic enzymes destroys the surrounding
tissues.
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5. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Gross appearance
 Liquid-like layer can be seen; pus should be
present. Yellowing, softening or swelling of the
tissue should be seen.
Malacia (softening, or loss of consistency) should
be present.
A cystic space should be present for tissue
resolution.
The tissue is in a liquid form and sometimes
creamy yellow because of pus formation.
Necrotic area: soft and filled with fluid.
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6. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
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7. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Microscopic appearance:
Structure-less tissue debris (no cellular outlines) –
Neutrophils, Macrophages and neutrophils, both
dead and alive, should be present.
 Debris and lysed cells should be seen with
inflammation.
Partial space should be filled with lipids and debris.
There is a loss of neurons and glial cells, with the
formation of clear space
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8. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Figure from: Robbins and Cotran pathologic basis of disease, 9th ed.
Figure 2.Gross appearance of infarct of kidney; B. Microscopy of normal kidney parenchyma;
Infarct of kidney
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9. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
 Mechanism
• Liquefaction is due to digestive action of the
hydrolytic enzymes released from dead cells
(autolysis) and leukocytes (heterolysis).
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10. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Caseous necrosis:
 Caseous necrosis occurs when the immune
system and body cannot successfully remove the
foreign noxious stimuli.
For example, tuberculosis
• The organism is not killed but rather contained.
• a yellow-white soft cheesy sphere that is enclosed
by a distinct border.
• White appearance is due to high accumulation of
white blood cells.
• Combination of coagulative and liquefactive
necrosis
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11. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Gross appearance:
• a yellow-white soft cheesy sphere that is
enclosed by a distinct border.
• White appearance is due to high accumulation of
white blood cells .
• The caseous mass is enclosed within a
connective tissue capsule.
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12. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Figure 3:Tuberculous lymphadenitis Caseous necrosis Microscopic appearance
• Figure from: Posted by Dr Vijay Shankar S | May 26, 2020 | Infectious , Environmental
& Nutritional Diseases, Practical Pathology, Slides
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GROSS APPEARANCE

13. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Microscopic appearance
• A Granuloma should be present.
• The core is necrotic and uniformly eosinophilic,
• which is surrounded by a border of activated
macrophages and lymphocytes.
• The core is structure less and should have debris
and lysed cells.
• Langhans giant cells may be seen, and
inflammation should also be noticed and present.
• There is a fibrous case surrounding and
enclosing the core; hence fibroblasts should also
be seen. .
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14. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
Figure 6:Tuberculous lymphadenitis Caseous necrosis Microscopic appearance
• Figure from: Posted by Dr Vijay Shankar S | May 26, 2020 | Infectious , Environmental & Nutritional Diseases, Practical Pathology,
Slides
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15. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
SUMM ARY

16. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS
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17. JIMMA UNIVARSTY
DEPARTMENT OF VETERINARY PATHOLOGY
MVSc PROGRAM
TYPE OF NECROSIS