Chronic inflammation

Chronic Inflammation M

Dr. ANANDAsst. Professor

• What is chronic inflamamtion• General Features • Sytemic effects of chronic inflammation• Cells involved• Types• Granuloma

Chronic Inflammation Chronic inflammation is inflammation

of prolonged duration (weeks or months) in which inflammation, tissue injury, and attempts at repair

coexist, in varying combinations.

CAUSES OF CHRONIC INFLAMMATION

1.Persistent Infection 2. Immune-mediated inflammatory diseases

3. Toxic Agents/FOREIGN BODY

• DOES SURGERY ASSOCIATED WITH CHRONIC INFLAMMATION

• YES

• HOW COME?

• SUTURE MATERIAL

GENERAL FEATURES

• MONONUCLEAR CELL INFILTRATION

• TISSUE DESTRUCTION//NECROSIS

• PROLIFERATIVE CHANGES

FIBROSIS ANGIOGENESIS

• CHRONIC INFLAMMATION ALWAYS ATTEMPTS TO HEALING

FEATURES

Chronic inflammation is characterized by: 1. Infiltration with mononuclear cells, which include

macrophages, lymphocytes, and plasma cells 2. Tissue destruction, induced by the persistent

offending agent or by the inflammatory cells

3. Attempts at healing by connective tissue replacement of damaged tissue, accomplished by proliferation of small blood vessels (angiogenesis) and, in particular, fibrosis.

• WHAT IS THE KEY PLAYER IN CHRONIC INFLAMMATION??

• MACROPHAGE

• DOES MACROPHAGE DIRECTLY COMES TO CHRONIC INFLAMMATION

• NO

• MONOCYTE

• MACROPHAGE

WHAT ARE THE PRODUCTS SECRETED BY MACROPHAGES??

• CYTOKINES-IL1, IL-2

• INTERFERONS –Y

• GROWTH FACTORS- TGF, PDGF, FGF,EGF• [TGF, PDGF------- to stimulate fibroblast]

• COMPLEMENT FACTORS[C]

• ENZYMES—Proteases, endonucleases, elastases

• Chemotactic factors

• NO

• Collagenases

• ANY OTHER??

• LYMPHOKINES

• IS NORMAL LYMPHOCYTE SECRETES LYMPHOKINES??

• CD4 Lymphocytes[[Th cells]

THE ROLES OF ACTIVATED MACROPHAGES IN CHRONIC INFLAMMATION :1.Inflammatory Tissue Injury2.Repair (Growth Factor Mediated)

Fig 2-24 (p72)

MACROPHAGE-LYMPHOCYTE INTERACTIONS IN CHRONIC INFLAMMATION  :

Fig 2-25 (p73)

TYPES

GRANULOMATOUS INFLAMMATION

Granulomatous inflammation is a distinctive pattern of chronic inflammation that is encountered in a limited number of infectious and some noninfectious conditions. Immune reactions are usually involved in the development of granulomas.

A granuloma is a cellular attempt to control an offending agent that is difficult to eradicate.

.

• In this attempt there is often strong activation of T lymphocytes leading to macrophage activation, which can cause injury to normal tissues

A granuloma is a focus of chronic inflammation consisting of

a microscopic aggregation of macrophages

that are transformed into epithelium-like cells, surrounded by a collar of mononuclear leukocytes, principally lymphocytes and occasionally plasma cells.

Types of GranulomasI. Foreign body granulomasII. Immune granulomas

Foreign body granulomasIncited by relatively inert foreign bodies. Typically, foreign body granulomas form around

material that are large enough to preclude phagocytosis by a single macrophage and do not incite any specific inflammatory or immune response.

.

Immune granulomas Caused by agents that are capable

of inducing an immune response which produces granulomas usually when the inciting agent is poorly degradable or particulate.

Giant CellsOlder granulomas develop an enclosing rim of

fibroblasts and connective tissue. Frequently, epithelioid cells fuse to form giant cells

in the periphery or sometimes in the center of granulomas.

These giant cells may attain diameters of 40 to 50 μm.

peripherally (Langhans-type giant cell) or haphazardly (foreign body–type giant cell).

• WHAT IS THE SHAPE OF EPITHELOID CELL

• ‘SOLE SHAPE’

SYSTEMIC EFFECTS OF CHRONIC INFLAMMATION

• Chronic inflammation is associated with following systemic features:

• 1. Fever. Invariably there is mild fever, often with loss of weight and weakness.

• 2. Anaemia:chronic inflammation is accompanied by anaemia of varying degree.

• 3. Leucocytosis. As in acute inflammation, chronic inflammation also has leucocytosis but generally there is relative lymphocytosis in these cases.

• 4. ESR. ESR is elevated in all cases of chronic inflammation.

• Which of the following is always present in chronic inflammation/

• A. Rubor• B. Edema• C. Leucocytosis• D. Increased ESR

MORPHOLOGY

• DRAW A NEAT LABELLED DIAGRAM OF GRANULOMA

• PATHOGENSIS OF GRANULOMA

• DIFFERENCE BETWEEN ACUTE &CHRONIC INFLAMMATION