Trichothiodystrophy leading to generalized trichorrhexis nodosa-like h
air changes with abnormal hair breakage is described in a 4-year-old g
irl. A marked deficiency of sulphur and the sulphur-containing amino a
cid, cystine, was detected in the biochemical analysis of the hair. Fu
rther investigation of the hair showed the morphological criteria of t
richothiodystrophy. Commonly related symptoms, such as mental retardat
ion, ichthyosis and increased sensitivity to sunlight, were not presen
t in our patient.