In this article, we will discuss Chronic Inflammation (Definition). So, let’s get started.
Inflammation of prolonged duration (lasting weeks or months) is labelled chronic inflammation. It is characterized by three simultaneously ongoing components:
1. Active inflammation
2. Tissue destruction
3. Attempts at repair
Chronic inflammation is differentiated from acute inflammation based on the absence of the cardinal signs of acute inflammation (redness, swelling, pain and increased temperature), as well as active vascular and cellular changes (hyperemia, exudation and neutrophil emigration). As the former is insidious in onset and of a longer duration, it is invariably accompanied by tissue manifestations of the immune response, repair, necrosis and fibrosis. The amount of fibrosis in the tissues is a function of the duration of chronic inflammation. Typically, chronic inflammation is low grade and associated with an asymptomatic clinical response. It has the following characteristics:
• Follows a solitary acute inflammatory reaction that fails to subside.
• Occurs without a clinically apparent acute phase.
• Results from repeated episodes of acute inflammation.
• Coexists with acute inflammation (acute on chronic inflammation).