Inflammation – what is it?

Atopic dermatitis is an inflammatory skin condition. But what does inflammation actually mean? There is hardly anyone who has never heard the word ‘inflammation.’ Nevertheless, many do not know exactly what is behind the term.

Inflammation is, first and foremost, a response of the immune system to a stimulus. This can include infections, internal diseases, or allergic reactions. It also applies to skin conditions such as psoriasis, atopic dermatitis, or other forms of eczema. Learn more about what exactly happens during an inflammatory reaction in the body in this article.

Causes of inflammation

Inflammation arises as a response of the immune system to a stimulus or trigger. Possible causes include the following:

  • Bacteria, fungi, viruses
  • Wounds, scratches, or foreign bodies (e.g., a thorn in the finger)
  • Chemical or physical influences (e.g., burns, corrosions)
  • Allergens, e.g., pollen or animal fur
  • Dysregulation of the immune system, e.g., in the case of atopic dermatitis
  • Internal causes, e.g., fat deposits in blood vessels

Inflammatory signs

In inflammation, the classic signs of inflammation occur. In total, there are five:

  • Warmth
  • Redness
  • Swelling
  • Pain
  • Disturbed function, e.g., impaired mobility of a joint

The inflammatory response is intended to limit dangers, defend against them, and repair any damage that has occurred. Depending on the strength and type of inflammation, these signs can be expressed differently and vary.

What happens during inflammation?

When inflammation occurs, a series of reactions take place in the body. Depending on the cause and the affected body part, there are different forms of inflammation. However, the processes of the inflammatory response are fundamentally similar:

  • Release of messenger substances from the immune system
  • Dilation of blood vessels and increased blood flow
  • Increased permeability of blood vessels
  • Infiltration of white blood cells

Release of inflammatory mediators

At the affected site, the immune system releases specific messenger substances that regulate the inflammatory response. These messenger substances include tissue hormones, histamine, and cytokines, which act on various immune cells and organs. They dilate blood vessels, allowing more blood to reach the site. This results in redness and warmth.

Containment of danger and repair

The walls of the blood vessels also become more permeable, allowing immune cells to easily enter the affected tissue. Numerous defense cells and white blood cells migrate to the site of the event, causing the tissue to swell. The white blood cells work together with so-called phagocytes to contain the danger and prevent its spread.

The messenger substances of the immune system now initiate the healing process. The healing process involves a vascularized connective tissue (granulation tissue), which is gradually replaced over time by the original tissue or scar tissue.

Acute and chronic inflammation

When the inflammation is limited to a specific area of the body, it is referred to as a local inflammatory response. However, inflammation can also occur in multiple areas or throughout the entire body.

Inflammation ceases when the cause is eliminated, and the affected tissue is repaired. The speed of resolution can vary depending on the extent of the inflammation. Typically, the healing of inflammation occurs over an extended period. The outcome may be complete healing, or there may be a scar at the site where the inflammation occurred.

If the body fails to eliminate the danger and the inflammation does not heal, it can spread, leading to chronic inflammation. This is the case, for example, with conditions like atopic dermatitis.

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Picture of Neurodermitis App Nia
Neurodermitis App Nia