Netherton syndrome presenting as congenital psoriasis.

A white boy had erythroderma and dense scale at birth. By 3 months the scale had localized to scalp, diaper area, and acral surfaces. Two biopsy specimens were read as psoriasiform dermatitis at 1 and 3 months. It was not until he was 10 months of age, when terminal hairs grew with nodose irregularities (trichorrhexis invaginatum), that the correct diagnosis of Netherton syndrome was made.