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Terminology of inflammation
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Time
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Extent
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Exudate
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Position
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Anatomy
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Suffix
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Acute
Chronic
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Local
Diffuse
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Serous
Fibrinous
Catarrhal
Purulent
Haemorrhagic
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Parenchy matous
Epithelial
Body cavities
Glands
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Nephr
Hepat
Rhin
Ent
Mast
Perito
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it is
it is
it is
it is
it is
it is
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- Sero – fibrinous
- Muco – purulent
- Fibrino – purulent
Fate of accumulation
Killing of Bacteria by neutrophils
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Degradation of bacteria by acid hydrolases in granules of neutrophils
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TB bacilli aroid degradation by enzymes & present insidephagocytic vacuoles
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Spreads infection to other sites through lymphatics
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Tissue injury
Harmful effects of chemotaxis, phagocytosis
Release of products into the extracellular space
- Lysosomal enzymes
- Free radicals
- Arachidonic acid metabolites like prostaglandins
- Based on the type of exudate
Catarrhal or mucous inflammation
- Exudates - Mucous
- Site - Occurs in cells capable of producing mucin
- Causes
- Mild irritants
- Chemicals (formalin, phenol, detergent)
- Food poisons
- Cold air, dust
- Bacterial and viral infections
- Gross appearance
- Clear, transparent, glistening
- Slimy material containing
- Water and mucous
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Catarrhal tracheitis - Broiler chicken
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- Microscopical appearance
- Proliferation of epithelial Cells
- Desquamation into exudates
- Neutrophils
- Mucus stained blue with haematoxylin
- Sequelae
- Recovery if cause is removed
- If not progresses to chronic
- On invasion with pyogenic organisms, it becomes mucopurulent
- Fibrosis
Serous inflammation
- Exudate - Plasma or thin watery fluid
- Site - Serous membranes - Peritoneum, pleura, pericardium, joints
- Causes
- Moderate - severe irritants
- Chemical irritants applied on skin → “BLISTERS”
- Traumatic injury
- Burns
- Viral infections – FMD, vesicular stomatitis
- Gross appearance
- Blister formation
- Clear, thin or watery fluid
- Sometimes mixed with fibrin gives a frosty glass appearance
- Microscopically
- Homogenous or finely granular exudates
- Stains pink with eosin (intensity varies with amount of protein in the exudates)
- Sequelae
- Fluid is resorbed if cause is removed
- If not organized or fibrosed , adhesions with cavities will develop with increased in fibrin content.
Fibrinous inflammation
- Exudate – Fibrin
- Sites
- Body cavities – Pleura, pericardial sac
- Epithelial surfaces (mucous, serous, cutaneous)
- Visceral organs (Lung, liver, kidneys)
- Causes – Severe irritant
- Viral diseases - Feline enteritis, malignant catarrhal fever
- Bacterial diseases – Salmonellosis, diphtheria
- Gross appearance
- Organ are tenser or hard
- Fibrin – stringy, yellowish net–like material
- On mucosal surfaces
- Casts – tubular organs
- Pseudomembrane formation - Masses of fibrin not firmly attached to the mucous membrane or peeled off easily.
- Diphtheretic membrane - Fibrin is firmly attached to the underlying tissue; the tissue undergoes coagulation necrosis
- Examples - Diphtheria, swine fever
- True membrane -Dead cells are included in exudates
- False membrane - Without dead epithelial cells
- “Bread butter appearance” - Fibrinous pericarditis
- Microscopical appearance
- Fibrin appears as dirty pink, net–like
- Entrapment of leucocytes and denuded cells found in the network
- Sequelae
- Indicates severe injury
- Not favorable – death supervenes
- Desquamation of fibrin on epithelial surface
- Reabsorption of from body cavities
- Organization
- Adhesions on serosal surfaces
Suppurative inflammation (Purulent)
- Exudate – Pus
- Factors essential for pus fomation
- Necrosis
- Neutrophils
- Digestion of necrotic tissue by protelytic enzymes
- Causes
- Pyogenic bacteria – Staphylococci, Streptococci, Escherichia coli
- Cornybacterium pyogenes, Actinomyces bovis etc
- Chemicals – turpentine, ZnCl2, Mercuric chloride
Suppuration / pus formation is not commonly seen in rabbits with tuberculosis due to the presence of antienzyme against proteases
- Characteristics of pus
- Composed of - necrotic
- Tissue cells
- Serum
- Alkaline – PH
- Color – white, yellow, green, red or black, red
- Consistency – thin, watery or creamy, thick
- Pus serum – liquor puris - does not coagulate
- Definitions in suppurative inflammation
- Cellulitis - Diffuse spreading suppurative inflammation of connective tissue
- Abscess - Collection of pus locally within a closed cavity in an organ or tissue
Haemorrhagic inflammation
- Exudate - Blood
- Cause - violent / severe irritant causes damage to blood vessels
- Bacterial – Black quarter, anthrax, haemorrhagic septicaemia
- Viral – Infectious laryngotracheitis in poultry
- Protozoal – Coccidiosis
- Gross - presence of blood
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Haemorrhagic inflammation - Tarry/black coloured digested blood
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Thrombosis of blood vessels - ischaemia
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Necrosis
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Saprophytes e.g. – Black quarter
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Gangrene
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Participants