The contribution of filaggrin null mutations to predicting atopic dermatitis (AD) treatment response is not clear, nor have such mutations been studied in the Finnish population. This study tested the association of the 4 most prevalent European FLG null mutations, the 2 Finnish enriched FLG null mutations, the FLG 12-repeat allele, and 50 additional epidermal barrier gene variants, with risk of AD, disease severity, clinical features, risk of other atopic diseases, age of onset, and treatment response in 501 patients with AD and 1,710 controls. AD, early-onset AD, palmar hyperlinearity, and asthma showed significant associations with the combined FLG null genotype. Disease severity and treatment response were independent of patient FLG status. Carrier frequencies of R501X, 2282del4, and S3247X were notably lower in Finns compared with reported frequencies in other populations. This data confirms FLG mutations as risk factors for AD in Finns, but also questions their feasibility as biomarkers in predicting treatment response.

Aim We collected evidence and safety data for topical tacrolimus in small children with atopic dermatitis (AD) and compared the usage with topical corticosteroid. Methods This was an interim analysis of 75 patients (55% female) at 1 year of an ongoing 3‐year randomised open‐label comparative follow‐up study of topical tacrolimus vs corticosteroid treatment. One‐ to three‐year‐old children with moderate‐to‐severe eczema referred to the Skin and Allergy Hospital in Helsinki, Finland, were enrolled. Results Efficacy parameters, the Eczema Area and Severity Index (EASI), Investigator's Global Assessment (IGA), transepidermal water loss (TEWL), eczema area, serum total immunoglobulin E (IgE) and the blood eosinophil count, showed improvement in both groups during the study. However, patients with signs of early sensitisation at baseline (elevated serum total IgE, elevated eosinophil count, positive prick tests or specific IgEs to aero or food allergens) had statistically significantly lower TEWL at the eczema site and a smaller eczema area at 12 months in the tacrolimus group. No severe adverse effects were seen during the treatment. Conclusion Children with AD and signs of early sensitisation appeared to benefit more from early tacrolimus than corticosteroid treatment. Small children may need stronger but nevertheless safe ointment options when treating moderate‐to‐severe AD.