The word inflammation derives from the Latin “inflammo” meaning “to set alight”. Occurrences such as burns, infections, radiation exposure, or frostbite trigger this reaction. It is likely that you have had this happen to you. In the case of questions as to the internal maneuvers that cause inflammation, I hope to shed some light on the topic.

First, the blood vessels dilate and blood flow increases to the area of damage. The blood vessels themselves become more permeable, allowing the plasma to escape from the blood into the extracellular fluid, which culminates in the swelling of the region that is affected. Leukocytes, or white blood cells, also escape from blood vessels in the area, and release chemicals that may cause pain. Together, these changes produce classic inflammation symptoms- redness, swelling, heat, pain, and tenderness.

As the progression of the inflammation occurs, leukocytes migrate in expanded numbers from the bloodstream and into the area that is injured. This response continues until the invading organisms and dead tissues have been removed. Next, the inflammation is resolved-the excess fluid is drained from the region by the lymphatics, the blood vessels constrict and thus become less permeable, and the redness, swelling, and heat subside.

Additionally, if tissue damage has occurred, the healing process will also involve regeneration of tissue-the repeated division of surviving tissue cells to replace the damaged ones. Not all tissues can regenerate, however, such as nerve and brain cells. In addition, extensive damage may not procure regenerative results.

Occasionally, surgical intervention may be required to aid the healing process. In some cases, dead cells, tissue, and bacteria may congregate to for pus, which in turn may collect and form an abscess, which may need to be drained. If there are large areas of dead tissue, the dead tissue requires removal.

A diagram of the inflammatory processes.