Forum for Nordic Dermato-Venereology Nr 1, 2018 | Page 26

Dissertation Atopic Dermatitis and Skin Barrier Function in Infancy and Early Childhood T eresa L øvold B erents Department of Dermatology, Oslo University Hospital, Oslo, Norway. E-mail: [email protected] Teresa Løvold Berents, a dermatologist at Oslo University Hospital, on September 7, 2017 defended her doctoral thesis titled “Atopic dermatitis and skin barrier function in infancy and early childhood” with Petter Gjersvik as main supervisor. Opponents were Åke Svensson, Malmö, Sweden, and Marit Saunes, Trondheim, Norway. Atopic dermatitis is a common, chronic and relapsing eczem- atous disease, typically manifesting in early life. The patho- genesis of atopic dermatitis is complex, with interactions of multiple genetic, biological and environmental factors leading to skin barrier dysfunction, altered immunological response and increased susceptibility to Staphylococcus aureus (S. aureus) colonization. The overall aim of the studies was to investigate some es- tablished and potential risk factors for the development of atopic dermatitis in early life, especially the role of skin barrier dysfunction, filaggrin mutation status, upper airway coloniza- tion of S. aureus, excessive weight-for-length and vitamin D levels. Infants living in south-east Norway and participating in a clinical trial on acute bronchiolitis treatment, either as patients (n = 404) or as controls recruited from the general population (n = 240), were assessed in infancy (mean age 5.1 months) and at a follow-up visit 18 months later (mean age 24.6 months), all within the period 2010–2014. Atopic der- matitis was diagnosed using the Hanifin & Rajka criteria and/ or based on caretakers’ history of physician-diagnosed atopic dermatitis. Disease severity was assessed using the SCORing Atopic Dermatitis (SCORAD) index. Data on weight and length at birth were obtained. Weight and length in infancy and at two years of age were measured at the clinical investigations. Transepidermal water loss (TEWL) was measured using an open chamber device on volar forearm and lateral upper arm to assess skin barrier function, with high levels indicating reduced barrier function. Samples for bacterial cultures were taken from the vestibulum nasi and fauces. Blood samples were analysed for vitamin D levels and for filaggrin mutations common in the European population. Measurements of TEWL on the lateral upper arm and volar forearm appeared equally appropriate to assess skin barrier function in infants (1). S. aureus colonization in vestibulum nasi and/or fauces was not associated with high TEWL (1). In children without atopic dermatitis in infancy, high TEWL in infancy was significantly associated with atopic dermatitis at follow-up 18 months later, indicating that skin barrier dys- function may precede the development of atopic dermatitis, although the sensitivity, specificity and positive predictive values were low (2). Atopic dermatitis at both time visits was associated with excessive weight-for-length in infancy, but not with excessive weight-for-length at birth or with early weight gain velocity (3). Vitamin D levels were not associated with From left to right: Siri Rostoft (acting dean), Marit Saunes (2 nd opponent), Åke Svensson (1 st opponent), Teresa Løvold Berents, Petter Gjersvik (main supervisor), Karin Lødrup Carlsen (co-supervisor), and Tom Stiris (evaluation committee chair). 24 Forum for Nord Derm Ven 2018, Vol. 23, No. 1