Hot, red, painful: What exactly is inflammation?
First of all, inflammation is actually a good thing. It is a defensive reaction of the immune system to a harmful stimulus. This can be pathogens, high pressure, heat, cold or injuries caused by foreign bodies or excessive strain. The aim of inflammation is to eliminate the stimulus as quickly as possible. This is noticeable externally through five main symptoms that occur in the affected area. These are redness, heat, swelling, pain and limited functionality. The redness and heat in particular are the reason why the whole thing is called inflammation.
The cardinal symptoms of inflammation – and what lies behind them
- Redness (rubor): The damaging stimulus attacks the cell walls of the blood vessels. This leads to the release of certain messenger substances (histamine, cytokines, prostaglandins), which in turn cause the blood vessels to expand. As a result, the blood flows more slowly in the affected area, allowing more messenger substances and defense cells to penetrate the affected tissue more easily. Since there is now more blood in the area, it appears red.
- Warming (Calor): More blood also means more heat that is transported from the inside of the body to the affected area. This is also useful because most physiological processes work better in warmth.
- Swelling (tumor): Due to the dilated blood vessels, the affected tissue fills with blood plasma, leukocytes and phagocytes and swells. While the hordes of defense cells do their work, the swelling has the side effect of creating a pressure stimulus that instinctively leads to a protective posture of the affected area.
- Pain (dolor): If nerve cells are affected by tissue damage, they signal this through pain. But some of the neurotransmitters also trigger a pain stimulus. In addition, the affected tissue is generously removed by the workers of the immune system before it is rebuilt as part of the healing process. Like pressure, pain also leads to instinctively protecting the affected area and thus supports healing.
- Limited functionality (Functio laesa): Depending on the location and severity of the damage, this leads to a more or less limited functionality of the affected area.
acute phase reaction
The first phase of an inflammatory reaction is called the acute phase reaction. In this phase, inflammatory mediators such as interleukins and interferons are released. These enter the liver via the bloodstream and lead to the production of more than 30 acute phase proteins, which in turn have specific tasks in wound healing. The concentration of one of these proteins, namely C-reactive protein (CRP), in the blood can rise up to a thousand times the normal value and is therefore a useful laboratory value for determining inflammation.
classification of inflammations
Time course :
- Peracute – sudden, severe inflammation, lasting up to two days, can be fatal
- Acute – sudden inflammation, lasting three to 14 days
- Subacute – moderately rapid onset, duration 14 to 30 days
- Chronic – slow to non-healing
- Recurrent – recurring
Appearance:
- Serous – discharge of protein-rich fluid, occurs predominantly in mucous membranes, a typical example is a runny nose
- Fibrinous – leakage of blood plasma, the fibrinogens contained in it cause coagulation, a grey to yellowish coating forms on mucous membranes
- Purulent – discharge of certain leukocytes, i.e. white blood cells, usually caused by bacterial infections
- Hemorrhagic – the vessels are so damaged that blood leaks out
Spread:
- Local – limited to one location
- Generalized – affects the whole body
A mosquito bite is also an inflammatory reaction
Further course of the inflammation
Severe inflammation can affect the entire body. The first symptoms are fatigue and fever, but it can also be accompanied by loss of appetite, increased pulse and blood pressure, tiredness, or chills. A blood test shows an increased number of white blood cells (leukocytes). However, the healing process usually begins after 12 to 36 hours. Just as the inflammatory reaction is initiated by various messenger substances, healing is also initiated by certain messenger substances, which are also known as inflammatory mediators. Destroyed cells and tissue residues that may have accumulated as pus are removed by phagocytes (macrophages). New tissue gradually forms from the edge of the inflammation inwards, starting with connective tissue and the finest blood vessels.
risk factors for increased inflammatory activity
The course of inflammatory reactions is also influenced by your own lifestyle. In particular, the consumption of animal fats can lead to increased inflammatory activity. Animal fats contain the omega-6 fatty acid arachidonic acid, which is used to produce inflammatory messengers. Inflammation also occurs more frequently in overweight people, because additional inflammatory tissue hormones are produced in abdominal fat. On the other hand, exercise that is gentle on the body and joints has an anti-inflammatory effect. Omega-3 fatty acids, found in nuts, seeds and fish, are involved in the formation of anti-inflammatory messengers, unlike omega-6 fatty acids, and should be consumed in sufficient quantities. The secondary plant substances and minerals found in fresh fruit and vegetables can also help to curb inflammatory reactions.
