Kategóriák: Minden - bacteria - inflammation

a Chan Samuel 16 éve

825

Pathologic Patterns of Inflammation

Abscesses and granulomas represent distinct patterns of inflammation, each with unique morphological and etiological characteristics. Abscess formation involves a localized collection of purulent tissue, often caused by the deep seeding of pyogenic bacteria.

Pathologic Patterns of Inflammation

Pathologic Patterns of Inflammation

Granulomatous

Caseating Granuloma

Syphilitic Gumma

TB nodule

Amorphous eosinophilic central zone

Develop necrosis in central area

Granuloma

Surrounded by collar of mononuclear leukocytes

Aggregation epithelioid macrophages

Foreign Body Granuloma

Eiptheloid and giant cells encompass the FB

Forms when material too large to be phagocytosed by a single macrophage

Immune Granuloma

Activation of T lymphocytes release cytokines

IFNy transforms macrophages into epithelioid and giant cells

IL-2 activates more T cells and perpetuates response

Macrophages engulf particles and present to T lymphocytes

Caused by insoluble particles that induce cell mediated immune response

Foreign Body Rxn

Beryliosis

Autoimmune Dz

Sarcoidosis

Crohn Dz

Specific Bacterial infxn

Brucellosis

Leprousy

TB

Predominant cell type is an activated macrophage with epithelial-like appearance
Distinct pattern of specific Chronic inflammation

Morphologic Patterns

Fibrinous Inflammation
Moephology

Few neutrophils present

Eosiniphilic meshwork of threads or amorphous coagulum

Associated with injury to membrane lined cavities

Peritonitis

Pericarditis

Occurs when exudate has a high plasma protein concentration

Suppurative Inflammation

Densely cellular exudates of neutrophils, cellular debris and edema

Pyogenic Bacteria

Bacterial meningitis

E.g. Acute appendicitis

Serous Inflammation
Commonly seen in burns and some viral infections (herpes)

Skin Blister

Accumulation of fluid with low plasma protein and cell content

Abcess

Surrounded by zone of

Vascular dilation

inflammatory infiltrate

Fibrin

Central region of necrotic leukocytes and cell debris

Liquifactive Necrosis

Can become Chronic

Neutrophils replaced by mononuclear leukocytes as chronic inflammation starts

Abscess encapsulated by granulation and fibrous tissue

Area of infection contained by fibrin deposition and processes of organization
Inflammation fails to destroy or remove pyogenic bacteria
Etiology
Deep seeding of pyogenic bactieria into tissue
form of suppurative inflammation
Cerebral Abcess
Lung Abcess
Localised collection of purulent inflammatory tissue

Ulcer

Morphology
Zone of granulation tissue beneath the slough
Acute inflammatory exudate of fibrin and neutrophils
Ulcerated surface covered in a layer of necrotic debris

Necrotic Slough

Pathogenesis
Occurs only if inflammatory necrotic area exist on/near the surface
Produced by sloughing of encrotic surface or tissue
Local excavation of the surface of an organ/tissue