Dermatitis can lead to bacterial infections primarily due to the disruption of the skin's protective barrier and the inflammatory response associated with the condition. Here are the key factors explaining this process:
Barrier Disruption: The skin normally acts as a physical barrier against pathogens, but when this barrier is broken, bacteria can enter more easily. Any initial barrier disruption can allow pathogens and bacteria to irritate the skin and cause an immune response. Once dermatitis is triggered it will cause inflammation and damage to the skin, which compromises the barrier's integrity further. This makes it easier for bacteria to colonize the skin.
Moisture and Exudate: Inflammatory conditions like dermatitis often produce exudate (fluid that oozes out of blood vessels due to inflammation) and lead to increased moisture on the skin's surface. Moist, damaged skin provides an ideal environment for bacterial growth.
Scratching and Trauma: Dermatitis is often accompanied by intense itching, which leads to scratching. Scratching can cause microtears or even larger wounds in the skin, further breaking down the barrier and creating entry points for bacteria.
Colonization of Pathogenic Bacteria: Certain types of dermatitis, such as atopic dermatitis (or eczema), are associated with colonization by bacteria like staphylococcus aureus (probably because eczema is associated with alkaline skin).
Reduced Effectiveness of Antimicrobial Peptides: The skin produces antimicrobial peptides as part of its defense against pathogens. Inflammatory conditions, like dermatitis, may perhaps reduce the production or effectiveness of these peptides, making the skin more susceptible to bacterial infections.
In summary, the combination of skin barrier disruption, increased moisture, scratching-induced trauma, altered immune response, and the presence of pathogenic bacteria makes individuals with dermatitis more prone to bacterial infections. Managing dermatitis effectively, including reducing inflammation and maintaining skin integrity, can help minimize the risk of these secondary infections.