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What is the difference between acute inflammation and chronic inflammation?

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Pathways of complement activation — inflammation The main function of complement proteins is to aid in the destruction of pathogens by piercing their outer membranes (cell lysis) or by making them more attractive to phagocytic cells such as macrophages (a process known as opsonization). Some complement components also promote inflammation by stimulating cells to release histamine and by attracting phagocytic cells to the site of infection.

Inflammation is a vital defense mechanism triggered by tissue damage or infection. The primary difference between acute and chronic inflammation lies in their duration and cellular composition.1

Acute Inflammation

Acute inflammation is a short-term response, typically lasting only a few days. It is characterized by rapid changes in blood flow and the migration of white blood cells, specifically neutrophils, to the injury site to eliminate harmful agents and initiate healing. While often beneficial, it can cause temporary discomfort like pain or itching.12

Chronic Inflammation

Chronic inflammation is a prolonged response that occurs when the body fails to eliminate the injurious agent or when healing is interfered with. It can arise from persistent infections, foreign materials, or autoimmune reactions. Unlike the neutrophil-heavy acute phase, the hallmark of chronic inflammation is the infiltration of macrophages, lymphocytes, and plasma cells. Because it is often persistent, chronic inflammation can lead to significant tissue damage and functional impairment.132