Diagnosis and outcome of congenital hyperammonemias.

A total of 21 patients were admitted to Aga Khan University Hospital with suspected congenital hyperammonemias during the period 1989 to 1992, 11 with acidosis and 10 without acidosis. Prominent clinical manifestations included positive family history (76%), onset in the first week of life (67%) and neurological manifestations (76%). Of patients with hyperammonemia and acidosis, 4 had severe metabolic acidosis with anion gap of 30mEq/L and above. Of patients with hyperammonemia without acidosis, 4 had ammonia level ranging from 1600-2000 micrograms/dl. Diagnosis was confirmed in only 1 patient and that was also done abroad. Overall mortality was 71%. These disorders are not uncommon in our country and should be suspected in all infants with above clinical or biochemical abnormalities.