COMA AND LIVER INSUFFICIENCY

Key words: Coma, Hyperammonemia, Urea-cycle disorders, Ornithine transcarbamylase deficiency, Phenylacetate, Benzoate

The work describes the case of a two-and-half-year-old girl who showed a clinical picture of neurologic impairment together with laboratory signs of liver insufficiency coupled with hyperammonemia. Some comments on this clinical case and how the diagnosis of ornithine transcarbamylase deficiency was reached are reported. The aim was to deepen the aetiology and the methodological approach to the pediatric non-traumatic coma and to summarize the urea cycle disorders (UCD) that are the most common inborn errors of metabolism causing hyperammonemia, also in the light of the novelties regarding the improvement of survival after its medical treatment. An enzymatic defect of this metabolic pathway results in the accumulation of serum ammonia and glutamate that are responsible of the symptoms, which range from mild cognitive deficit to deep coma and may vary in severity from fatal neonatal hyperammonemia to asymptomatic adults. The conservative treatment consists of protein-restricted diet and alternative pathway medications, such sodium benzoate and sodium phenylacetate. In case of failure, dialysis and liver transplantation are the other possible choices. Indications on and problems arising from the latter invasive option are discussed, too.