INFLAMMATION AND REPAIR

                             ROBINS BASIC PATHOLOGY

INFLAMMATION 

– Inflammation is a protective response

 – involving host cells, blood vessels, and proteins, and other mediators

 – that is intended to eliminate the initial cause of cell injury, as well as the necrotic cells and tissues

 – resulting from the original insult and to initiate the process of repair. 

DEFINITION

–– Inflammation is a protective response involving host cells, blood vessels, and proteins, and other mediators that are intended to eliminate the initial cause of cell injury, as well as the necrotic cells and tissues resulting from the original insult, and to initiate the process of repair.

INFLAMMATION

– inflammation helps clear infections and other noxious stimuli – and initiates repair, – the inflammatory reaction and the subsequent repair process can themselves cause considerable harm.

                                      INJURY  !

Injury may accompany entirely normal, called beneficial inflammatory reactions.

Goal Of The Inflammatory Reaction 

– The cells and molecules of host defense, including leukocytes and plasma proteins, normally circulate in the blood, and the goal of the inflammatory reaction is to bring them to the site of infection or tissue damage.

Cardinal Signs Of Inflammation

–Heat  

– Redness 

– Swelling 

– Pain 

 – Loss Of Function

– The external manifestations of inflammation, often called its cardinal signs, are heat, redness, swelling, pain, and loss of function. The first four of these were described more than 2000 years ago by a Roman encyclopedist named Celsius, who wrote the then famous text De Medicine, and the fifth was added in the late 19th century by Rudolf Virchow, known as the “father of modern pathology.” These manifestations occur as consequences of the vascular changes and leukocyte recruitment and activation. 

Steps Of Inflammation

– RECOGNITION OF MICROBES, NECROTIC CELLS, AND FOREIGN SUBSTANCES

– VASCULAR CHANGES 

– CELLULAR EVENTS: Leukocyte Recruitment and Activation

– CHEMICAL MEDIATORS – REGULATORS OF INFLAMMATION 

– TISSUE REPAIR

Inflammation is induced by chemical mediators that are produced by host cells in response to injurious stimuli

Table 2-1 Feature of Acute and Chronic inflammation 

-Feature                                           -Acute                                                           -Chronic                                    

1-Onset   1-Fast: minutes or hours                           1-Slow :Days

2-Cellular Infiltrate  2 -Mainly neutrophils                       2 -Monocytes/macrophages and                                                                                                                                   lymphocytes

3-Tissue injury, fibrosis   3 -Usually mild and self-limited                    3 -Often severs and Progressive

4-Local and systemic signs   4-Prominent                      4-Less prominent ;May be subtle