Family with intermittent maple syrup urine disease

Maple syrup urine disease: treatment of the acutely ill newborn

Three patients with maple syrup urine disease were treated during the acute neonatal stage. Multiple exchange transfusions proved to be a satisfactory means of achieving rapid clinical and biochemical improvement during this phase. On the other hand, evidence is provided suggesting that in addition to exchange transfusions, a high calorie intake above 150 Cal/kg body weight/day is necessary to lower the plasma concentration of the branched chain amino acids to near-normal levels. As long as this calorie intake was not provided, further exchange transfusions failed to lower the plasma leucine concentration to below 17 mg/100 ml in one patient. It is assumed that this high calorie intake is necessary to prevent the breakdown of endogenous protein. Treatment of acute episodes in maple syrup urine disease should therefore not only eliminate the elevated alpha-keto acids and branched chain amino acids quickly (i.e. by multiple exchange transfusions or peritoneal dialysis), but in addition should provide a high calorie intake.

Mild variant of maple syrup urine disease

Amino acids analysis were made on serum and cerebrospinal fluid samples of a Japanese 5-month-old infant suffering from irritability and mental retardation noticed at 2 months of age. Excessive amounts of branched-chain amino acids and of keto acids were detected in those samples and the large quantity of keto acids was found in urine with a qualitative 2,4-dinitro-phenyl-hydrazin test and with quantitative estimation. When thiamine hydrochloride (100 mg/day) was administered orally for 7 days to the patient fed with the cow's milk formula containing 2.1 gm/dl milk protein, there was no improvement of the branched-chain amino acidemia. Urinary keto acids, however, showed a marked decrease 7 days after the administration of thiamine hydrochloride. An overnight fast for 13 h resulted in normoglycemia. There was found no difference of blood L-lencine level between both parents and normal infants to whom L-leucine was loaded. The relation between decarboxylase activity for keto acids of branched-chain amino acids and thiamine hydrochloride was studied clinically, in the present communication.