Trichothiodystrophy and Associated Anomalies: A Variant of SIBIDS or New Symptom Complex?

Abstract: Trichothiodystrophy is characterized by sparse, short, sulfur‐deflclent hair. Numerous symptom complexes have been described in which the hair abnormaiity represents a constant feature. We report a boy with trichothiodystrophy, ichthyotic skin changes, onychodystrophy, chronic neutropenia, osteoscierosis, hypothyroidism, nystagmus, growth and mentai retardation, and microcephaiy, who developed a progressive encephalopathy with ataxia and optic atrophy at 2.5 years of age. in addition to a deficient cystine ievei identified on a hair sampie, a disturbance in the composition of other amino acids was present. Ai‐though features were reminiscent of osteoscierosis, ichthyosis, brittie hair due to trichothiodystrophy, impaired inteliigence, decreased fertiiity, and short stature (SIBIDS) and couid represent a variant of this disorder, findings in our patient may refiect a new trichothiodystrophy symptom compiex that carries a poor prognosis for survivai beyond chiidhood.