DIAGNOSIS OF TRICHOTHIODYSTROPHY IN 2 SIBLINGS

Trichothiodystrophy (TTD) is a rare autosomal recessively inherited di sorder which is characterized by sparse and brittle hair with low cyst ine content. It is often associated with physical and mental retardati on. We report 2 cases of TTD in 2 sibs who were born to related parent s. The children showed clinical features typical of TTD and in additio n other symptoms such as epilepsy, ataxia, spasticity, strabismus, ato pic dermatitis, dysarthria and hyperextensible finger joints. The sulf ur content of hair was reduced to about 50% of normal values and scann ing electron microscopy of hair showed trichorrhexis nodosa, trichosch isis, missing cuticle scales with weathering of hair shafts. Under pol arizing microscopy an alternating dark and bright banding was found. T he present cases show that the correct diagnosis of TTD in practice ca n be impeded for many years because of the heterogeneous clinical appe arance and that the determination of the sulfur content in hair is a s imple but indispensable method.