D2.300 - Food allergy and food sensitization in children with Netherton syndrome

Netherton syndrome (NS) is a rare multisystemic autosomal recessive disorder classified among syndromic ichthyoses. It is caused by a loss-of-function mutation in the SPINK5 gene, which encodes the LEKTI protein that inhibits epidermal serine proteases, leading to impaired keratinization and epidermal barrier dysfunction. The syndrome is characterized by a clinical triad of congenital ichthyosiform erythroderma, hair shaft abnormalities (“bamboo hair”), and a predisposition to allergic diseases.

Thirteen patients with NS aged 2 to 17 years were examined. An assessment of the allergic history was carried out, and the levels of total IgE and specific IgE (sIgE) to 10 allergens (chicken egg white and yolk, cow's milk, casein, beef, cod, gluten, wheat, soy, rice, buckwheat, oats, corn, apple, banana) were determined.

All children with NS had IgE-mediated multiple food allergies (FA). Combined skin and gastrointestinal symptoms of FA were found in 84.62% of patients, only skin symptoms in 7.69%, and gastrointestinal symptoms in 7.69%. High levels of total IgE were found in 92.4%, levels exceeding 1000 IU/ml in 46.2% of patients. Sensitization to food allergens was detected in all patients: all patients were sensitized to chicken egg protein, 84.6%, to chicken egg yolk, 69.2% to cow's milk proteins, 76.9% to beef, cod, soy, and buckwheat, 61.5% to gluten, 92.3% to rice, and 84.6% to oats, apples, and bananas. One child with multiple FA had an extremely high level of sensitivity to cod, experiencing angioedema after eating fish. Another child with multiple FA had an extremely high level of sensitivity to gluten and a very high level of sensitivity to corn. Noteworthy are the relatively low levels of sensitization to cow's milk protein and casein compared to the levels of sensitization to other proteins, which might be explained by these patients' long-term adherence to a dairy-free diet.

Given the predisposition to food allergies in children with NS, early identification of the sensitization spectrum and a coordinated, individualized dietary treatment strategy are essential.