InflammationInflammationDR .HALA BADAWI

LECTURER OF PATHOLOGY

DEFINITION:DEFINITION: Inflammation is the reaction of vascularized living Inflammation is the reaction of vascularized living

tissue to local injury. It is a series of vascular and tissue to local injury. It is a series of vascular and cellular reactions aiming to protect the body against cellular reactions aiming to protect the body against the injurious agent .the injurious agent .

TYPES:TYPES: -Acute: sudden onset and short duration ( hours - -Acute: sudden onset and short duration ( hours -

days) days) -Chronic: gradual onset and long duration ( days --Chronic: gradual onset and long duration ( days -

years) years)

INFLAMMATIONINFLAMMATION

INFLAMMATIONINFLAMMATION

CAUSES:CAUSES:

Living irritantsLiving irritants

Bacteria, viruses, parasites and fungiBacteria, viruses, parasites and fungi

Non-living irritantsNon-living irritants Physical, chemical and mechanicalPhysical, chemical and mechanical AntigensAntigens

• Caused by an irritant of short duration of Caused by an irritant of short duration of actionaction

• The tissue response is rapid i.e. sudden onsetThe tissue response is rapid i.e. sudden onset• Inflammation lasts for days or weeksInflammation lasts for days or weeks• Characterized by presence of fluid exudate Characterized by presence of fluid exudate

and cellular exudate mainly polymorph-and cellular exudate mainly polymorph-nuclear leucocytesnuclear leucocytes

ACUTE INFLAMMATIONACUTE INFLAMMATION

• REDNESSREDNESS• HOTNESSHOTNESS• SWELLINGSWELLING• PAINPAIN• LOSS OF LOSS OF

FUNCTIONFUNCTION

CARDINAL SIGNS AND SYMPTOMS OF CARDINAL SIGNS AND SYMPTOMS OF ACUTE INFLAMMATIONACUTE INFLAMMATION

Major events in inflammationMajor events in inflammation

Vascular events Cellular events

•Vasodilatation of arterioles and capillaries

•Increased blood flow

•Slowing of blood stream

•Increased capillary permeability

Formation of InflammatoryFluid exudate

• Margination of leucocytesMargination of leucocytes• Emigration of leucocytesEmigration of leucocytes• Emigration of monocytesEmigration of monocytes• Chemotaxis: Chemotaxis: (directed movement towards (directed movement towards

area of inflammation)area of inflammation)• Phagocytosis:Phagocytosis: (engulfment of bacteria and (engulfment of bacteria and

necrotic tissue)necrotic tissue)

Vascular Events in inflammation

•Vasodilatation of arterioles and capillaries

•Increased blood flow

•Slowing of blood stream

•Increased capillary permeability

Cellular Events in inflammation

• Margination , Emigration of neutrophils & monocytesMargination , Emigration of neutrophils & monocytes• Chemotaxis & phagocytosis Chemotaxis & phagocytosis

Phagocytosis,Killing & degradation

Chemical Mediator of Inflammation

CHEMICAL MEDIATORSACTIONS

Bind to specific receptors on the cells

Vasodilatation

Increase vascular permeability

Chemotaxis

Histamine

Prostaglandins

C3a & C5a

Histamine, kinins, leukotriens

Leukotriens & lysosomal components

Function:Function:1.1. It dilutes bacterial toxins and chemical irritants.It dilutes bacterial toxins and chemical irritants.2.2. It brings antibodies to the area of inflammation.It brings antibodies to the area of inflammation.3.3. It brings the chemical mediators derived from plasma to the It brings the chemical mediators derived from plasma to the

area.area.4.4. It contains fibrinogen which changes to fibrin by activation It contains fibrinogen which changes to fibrin by activation

of clotting system. Fibrin helps in localization of of clotting system. Fibrin helps in localization of inflammation by surrounding the area .inflammation by surrounding the area .

Fate:Fate: Fluid exudate is absorbed by lymphatics. Fluid exudate is absorbed by lymphatics.

The Inflammatory Fluid ExudateThe Inflammatory Fluid Exudate

Fate of Acute inflammationFate of Acute inflammation

Complete resolutionComplete resolution Healing by scarringHealing by scarring Progression and spread:Progression and spread:

(direct, lymphatic & blood spread)(direct, lymphatic & blood spread) ChronicityChronicity

TYPES OF ACUTE INFLAMMATIONTYPES OF ACUTE INFLAMMATION

SUPPURATIVESUPPURATIVE INFLAMMATIONINFLAMMATION

NON-SUPPURATIVENON-SUPPURATIVE INFLAMMATIONINFLAMMATION

Types:Types:

I- SUPPURATIVE INFLAMMATIONI- SUPPURATIVE INFLAMMATION

I-Localized Supp. Inflamm.

Abscess, furuncle,

carbuncle

II- Diffuse Supp. Inflamm.

Cellulitis, Suppurative appendicitis, Suppurative cholecystitis, Suppurative peritonitis, Suppurative meningitis

…etc.

I- LOCALIZED SUPPURATIVE INFLAMMATIONI- LOCALIZED SUPPURATIVE INFLAMMATION

carbunclecarbunclefurunclefuruncle

AbscessAbscess

AbscessAbscess DefinitionDefinition:: Cavity containing Cavity containing

puspus (pus is formed of (pus is formed of

fluid exudate, fluid exudate, fibrin,pus cells, fibrin,pus cells, polymprph, polymprph, macrophages, macrophages, necrotic tissue and necrotic tissue and bacteria)bacteria)

AbscessAbscess Fate of abscess:Fate of abscess: Small abscess:Small abscess:

Pus may be absorbed followed by healingPus may be absorbed followed by healing Large abscess: Large abscess:

Should be evacuated, spontaneous or surgicalShould be evacuated, spontaneous or surgical

AbscessAbscessComplication of abscessComplication of abscess:: Ulcer (local defect on Ulcer (local defect on

the surface)the surface) Sinus (blind end tract) Sinus (blind end tract)

& Fistula (tract with & Fistula (tract with two openings)two openings)

Hemorrhage & Hemorrhage & gangrenegangrene

Spread of infectionSpread of infection

Ulcer

GangreneSinus

II- DIFFUSE SUPPURATIVE INFLAMMATIONII- DIFFUSE SUPPURATIVE INFLAMMATION

Acute supp. appendicitisDiffuse sup.cholecystitis Suppurative meningitis

Cellulitis

Cellulitis

Catarrhal inflammation: Catarrhal inflammation: e.g.common colde.g.common cold Pseudo-membranous inflam.: Pseudo-membranous inflam.: e.g.diphtheriae.g.diphtheria Fibrinous inflammation: e.g. Fibrinous inflammation: e.g. fibrinous pericarditis, fibrinous pericarditis,

fibrinous pleurisy, fibrinous peritonitis.fibrinous pleurisy, fibrinous peritonitis. Serous inflammation: Serous inflammation: e.g. burnse.g. burns Haemorrhagic inflammationHaemorrhagic inflammation Gangrenous (necrotizing) inflammationGangrenous (necrotizing) inflammation Allergic inflammationAllergic inflammation

NON-SUPPURATIVE INFLAMMATIONNON-SUPPURATIVE INFLAMMATION

NON-SUPPURATIVE INFLAMMATIONNON-SUPPURATIVE INFLAMMATION

Fibrinous pleurisy Fibrinous pericarditis

Fibrinous peritonitisHaemorhagic pericarditis.

Gangrenous inflammation

Fibrinous pericarditis

Characterized by:Characterized by: Mild irritant with a prolonged actionMild irritant with a prolonged action Tissue response is gradual and prolonged Tissue response is gradual and prolonged

(mild vascular dilatation and congestion)(mild vascular dilatation and congestion) Tissue destructionTissue destruction is progressive and is progressive and

gradually replaced by gradually replaced by fibrous tissuefibrous tissue with with thickening and narrowing of blood vessels thickening and narrowing of blood vessels (endarteritis obliterans)(endarteritis obliterans)

Scanty fluid exudate Scanty fluid exudate

CHRONIC INFLAMMATIONCHRONIC INFLAMMATION

Composed of:Composed of: LymphocytesLymphocytes Plasma cellsPlasma cells MacrophagesMacrophages Giant cellsGiant cells Esinophils in parasitic and allergic Esinophils in parasitic and allergic

inflammationinflammation..

Chronic Inflammatory Cellular Chronic Inflammatory Cellular ExudateExudate

1- 1- Chronic non-specific inflammationChronic non-specific inflammation Different irritants produce inflammatory Different irritants produce inflammatory

reaction of the same microscopic picturereaction of the same microscopic picture

2- 2- Chronic specific inflammationChronic specific inflammation Each irritant produces inflammation of a Each irritant produces inflammation of a

characteristic microscopic picturecharacteristic microscopic picture

Types of Chronic InflammationTypes of Chronic Inflammation

Chronic non-specific inflammation

Definition:Definition: A type of chronic inflammation A type of chronic inflammation

characterized by focal accumulation of large characterized by focal accumulation of large number of macrophages together with number of macrophages together with lymphocytes, plasma cells, giant cells and lymphocytes, plasma cells, giant cells and fibroblasts forming tiny granulesfibroblasts forming tiny granules

GranulomaGranuloma

1-Infective granuloma1-Infective granuloma a. Bacterial e.g.TB, leprosy & syphilisa. Bacterial e.g.TB, leprosy & syphilis b. Parasitic e.g. Bilharziasisb. Parasitic e.g. Bilharziasis c. Fungal e.g. madura footc. Fungal e.g. madura foot 2-Non-infective granuloma2-Non-infective granuloma a. Silicosis and asbestosisa. Silicosis and asbestosis b. Foreign body granulomab. Foreign body granuloma 3-Granuloma of unknown cause3-Granuloma of unknown cause SarcoidosisSarcoidosis

Types of GranulomasTypes of Granulomas

Granuloma

Tuberculous granuloma of the lung