Skin scratching and intestinal changes: What’s the link?

Patients with atopic dermatitis (AD) who scratch their skin may have more severe food allergies, according to a recent study published online in Immunity. The study authors connected skin scratching to intestinal changes that make it easier for allergens to enter tissues. To investigate this link, the researchers applied and removed tape to the skin of mice — replicating the scraping away of skin cells from scratching. In the mice models, this led to increased food-related anaphylaxis.

The researchers found that scratching signals interleukin 33 (IL-33), which then enters the patient's bloodstream and makes its way to the intestines, where it interacts with IL-25. IL-33 and IL-25 interact and activate type 2 innate lymphoid cells, which in turn produce the proteins IL-13 and IL-4. Lastly, IL-13 and IL-4 cause mast cells to expand in the gut, leading to increased food allergen sensitivity.

The investigators conducted intestinal biopsies in eight children — four with atopic dermatitis and four without — to see whether there was a similar effect in humans. As expected, the intestines of the four children with AD contained more mast cells than the intestines of children without AD.

Can the elimination diet hurt pediatric atopic dermatitis patients? Find out in DW Weekly.

Sent from my iPhone

Benjamin Hidalgo-Matlock
Skin Care Physicians of Costa Rica

Clinica Victoria en San Pedro: 4000-1054
Momentum Escazu: 2101-9574

Please excuse the shortness of this message, as it has been sent from
a mobile device.