Helical hairs: a new hair anomaly in a patient with Netherton's syndrome.

A new hair shaft defect, helical hair, is presented. This hair abnormality was found to accompany trichorrhexis invaginata and pili torti in an infant with Netherton's syndrome. The patient's main clinical features included erythroderma since birth, failure to thrive, recurrent infections, hepatosplenomegaly, lymphadenopathy, eosinophilia, hypergammaglobulinemia, and high serum IgE levels. A possible mechanism for the formation of helical hair is reviewed.