Psoriasiform napkin dermatitis-a follow-up study.

One hundred and twenty-three children who had napkin dermatitis, with or without a secondary sensitization eruption, in infancy were reviewed 5-13 years later. Of the seventy-one who had a predominantly psoriasiform secondary eruption, twelve (17%) had psoriasis at review-three (4%) had atopic eczema. None of the forty treated for a predominantly seborrhoeic secondary eruption had psoriasis at review-15 (37%) had atopic eczema. The psoriasiform group had the highest incidence of psoriasis and the lowest incidence of atopy among first degree relatives. The converse incidence was found in the seborrhoeic group. It is suggested that infants who develop psoriasiform napkin dermatitis have a psoriatic diathesis.