[Combined exchange transfusion and peritoneal dialysis treatment in a neonatal case of methylmalonic acidemia with severe hyperammonemia].

A case of methyl-malonic acidemia with severe neonatal hyperammoniemia is presented. Treatment during the first days of live with exchange-transfusion, with protein-free blood and peritoneal dialysis induced a decrease of blood ammonia values from 1360 to 270 micrograms/dl and the correction of systemic metabolic acidosis. Continuation of treatment by dietary means was followed by normalization of clinical status and almost total correction of the urinary excretion of methyl-malonic and propionic acids, but the patient died at 33 days of life due to an intercurrent infection. This case, together with a case previously reported of propionic acidemia with neonatal hyperammoniemia and prolonged survival, demonstrates that complementary treatment by means of exchange transfusion and peritoneal dialysis is mandatory in all cases of neonatal hyperammoniemia of metabolic origin, since survival without irreversible neurological damage is possible.