Treatment of complete ornithine transcarbamylase deficiency with nitrogen-free analogues of essential amino acids.

A male infant with complete hereditary deficiency of hepatic ornithine transcarbamylase was fed a low-protein diet (1 gm/kg/day) supplemented with nitrogen-free analogues of essential amino acids from the age of 2 days until his death at 5 months. Blood ammonia and plasma acid concentrations were maintained in the near normal range during most of his lifetime. Growth and development were entirely normal. Abrupt, unprecipitated hyperammonemia, which could not be reversed by intensive treatment, led to his death. To our knowledge, this child lived longer than any previously reported infant with OTC deficiency of this severity.