[Lesch-Nyhan syndrome without self-mutilation: biochemical and morphological studies on blood cells (author's transl)].

Absent enzyme activity of hypoxanthine-guanine-phosphoribosyl transferase in erythrocytes was demonstrated in the blood from a 21-year-old man with spastic tetraplegia, choreoathetosis, oligophrenia, and hyperruricaemia which developed after birth. But there was no tendency towards self-mutilation, considered to be characteristic of the full-blown picture of the disease. This case thus runs counter to the view that the enzyme defect is the cause of the inevitable, stereotyped change in behaviour. Unusual morphological changes of all blood-cell systems confirm the dependence of nucleic acid synthesis on the "salvage pathway" of the purine nucleotides, which is abnormal in this inherited disease.