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How can repeated episodes of acute inflammation lead to 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.

Repeated episodes of acute inflammation can lead to chronic inflammation when the underlying agent causing the injury is not successfully eliminated or when the body's healing process is interfered with.1

While acute inflammation is a short-term defense mechanism intended to localize and remove injurious agents, its persistence or recurrence prevents the tissue from returning to a healthy state. When the inflammatory response is repeatedly triggered, or if the initial cause—such as an infectious organism or a foreign material—remains present, the body may shift from an acute response to a chronic one.12

In this state, the site of injury becomes infiltrated by macrophages, lymphocytes, and plasma cells. Macrophages, which are the principal cells of chronic inflammation, continue to release factors that contribute to ongoing tissue damage and functional impairment. This transition represents a failure of the body to resolve the initial injury, resulting in a prolonged and potentially damaging inflammatory state.12