Acute Inflammation
Acute Inflammation
The survival of all organisms requires that they eliminate foreign invaders, such as infectious pathogens, and damaged tissues. These functions are mediated by a complex host response called inflammation.
Definition of inflammation Inflammation is fundamentally a protective response, the ultimate goal of which is to rid the organism of both the initial cause of cell injury (e.g., microbes, toxins) and the consequences of such injury (e.g., necrotic cells and tissues)
The process of inflammation is usually described by the suffix “itis”
[The components of the inflammatory reaction that destroy and eliminate microbes and dead tissues are capable of also injuring normal tissues. Therefore, injury may accompany entirely normal, beneficial inflammatory reactions, and the pathology may even become the dominant feature if the reaction is very strong (e.g., when the infection is severe), prolonged (e.g., when the eliciting agent resists eradication), or inappropriate (e.g., when it is directed against self-antigens in autoimmune diseases. or against usually harmless environmental antigens in allergic disorders).
Some of the most vexing diseases of humans are disorders in which the pathophysiologic basis is inappropriate, often chronic, inflammation. This is why the process of inflammation is fundamental to virtually all of clinical medicine.]
ACUTE INFLAMMATION
Acute inflammatory reactions are triggered by a variety of stimuli: • Infections (bacterial, viral, parasitic) and microbial toxins • Trauma (blunt and penetrating) • Physical and chemical agents (thermal injury, e.g., burns or frostbite; irradiation; some environmental chemicals) • Tissue necrosis (from any cause) • Foreign bodies (splinters, dirt, sutures) • Immune reactions (also called hypersensitivity reactions
Cardinal signs of inflammation
[pic]
Celsus, a Roman writer of the first century AD, first listed the four cardinal signs of
The survival of all organisms requires that they eliminate foreign invaders, such as infectious pathogens, and damaged tissues. These functions are mediated by a complex host response called inflammation.
Definition of inflammation Inflammation is fundamentally a protective response, the ultimate goal of which is to rid the organism of both the initial cause of cell injury (e.g., microbes, toxins) and the consequences of such injury (e.g., necrotic cells and tissues)
The process of inflammation is usually described by the suffix “itis”
[The components of the inflammatory reaction that destroy and eliminate microbes and dead tissues are capable of also injuring normal tissues. Therefore, injury may accompany entirely normal, beneficial inflammatory reactions, and the pathology may even become the dominant feature if the reaction is very strong (e.g., when the infection is severe), prolonged (e.g., when the eliciting agent resists eradication), or inappropriate (e.g., when it is directed against self-antigens in autoimmune diseases. or against usually harmless environmental antigens in allergic disorders).
Some of the most vexing diseases of humans are disorders in which the pathophysiologic basis is inappropriate, often chronic, inflammation. This is why the process of inflammation is fundamental to virtually all of clinical medicine.]
ACUTE INFLAMMATION
Acute inflammatory reactions are triggered by a variety of stimuli: • Infections (bacterial, viral, parasitic) and microbial toxins • Trauma (blunt and penetrating) • Physical and chemical agents (thermal injury, e.g., burns or frostbite; irradiation; some environmental chemicals) • Tissue necrosis (from any cause) • Foreign bodies (splinters, dirt, sutures) • Immune reactions (also called hypersensitivity reactions
Cardinal signs of inflammation
[pic]
Celsus, a Roman writer of the first century AD, first listed the four cardinal signs of