• atopic diathesis;
  • perioral dermatitis;
  • rosacea;
  • skin barrier function;
  • transepidermal water loss


Background  Rosacea and perioral dermatitis (PD) are common dermatoses, the aetiology and pathogenesis of which remain speculative.

Objectives  To investigate skin barrier function and features of atopy in both diseases.

Methods  We studied 75 patients with rosacea and 75 with PD. Transepidermal water loss (TEWL) was measured in three regions of the face (lateral chin, perinasal cheek, side of the nose) and the patients were assessed for atopy by clinical criteria, prick tests and specific IgE against a mixture of aeroallergens (CAP SX1). The control group consisted of 125 individuals with no history of rosacea, PD or active atopic disease.

Results  In patients with PD, TEWL was significantly increased (P < 0·001) at all measurement points in comparison with the rosacea and control groups. Significantly (P < 0·001) higher values were also found regarding history and clinical signs of an atopic diathesis, prick test reactivity and specific IgE against aeroallergens.

Conclusions  PD is characterized by a skin barrier disorder of facial skin. It differs from rosacea in that it involves a significantly increased TEWL and features of an atopic diathesis. However, it remains disputed as to whether PD is an individual skin disease or a subtype of rosacea in atopic patients.