By Gary M. White, MD

Trichothiodystrophy (TTD) is an autosomal-recessive genodermatosis with a wide variety of presentations. The unifying theme, however, is brittle and sulfur-deficient hair. The hair characteristically shows alternating light and dark bands under polarizing light (“tiger tail” banding which is diagnostic). Various ectodermal and neuroectodermal syndromes related to trichothiodystrophy have been described including IBIDS, PIBIDS, and Tay syndrome.


The hair is brittle. Approximately half of TTD patients demonstrate an exaggerated response to ultraviolet radiation, resulting in severe sunburns after minimal exposure. In contrast to xeroderma pigmentosum, patients with TTD do not show the increased freckle-like pigmentation and the high frequency of light-induced skin cancer. Nail abnormalities, such as onychodystrophy, splitting, ridging, or thickening may occur. An ichthyosis may occur.


JAAD August 2010 Volume 63, Issue 2, Pages 323–328


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