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Prenatal benzoate treatment in urea cycle defects
A M Das1, S Illsinger, H Hartmann
1Department of Paediatrics II, Hannover Medical School, Carl-Neuberg Str. 1, D-30625 Hannover, Germany. das.anibh@mh-hannover.de
Archives of Disease in Childhood. Fetal and Neonatal Edition
|November 13, 2008
Summary
Prenatal benzoate administration to mothers with urea cycle defects (UCD) safely transfers therapeutic benzoate levels to fetuses. This approach may improve metabolic stability in newborns with UCD by reducing hyperammonaemia.
Area of Science:
- Medical Genetics
- Biochemistry
- Neonatology
Background:
- Severe urea cycle defects (UCD) cause life-threatening hyperammonaemia in newborns, often leading to neurological damage or death.
- Benzoate is a nitrogen-scavenging agent used to manage hyperammonaemia in UCD patients.
- Current treatment typically starts benzoate after birth, but prenatal administration is hypothesized to enhance metabolic stability.
Observation:
- Two fetuses diagnosed with UCD (citrullinaemia and ornithine transcarbamylase deficiency) received prenatal benzoate via maternal infusion.
- Benzoate levels were measured in maternal, umbilical cord, and neonatal blood samples.
- Demonstrated successful transplacental transfer of benzoate.
Findings:
- Therapeutic benzoate concentrations were achieved in umbilical cord blood and neonates.
- Postnatal plasma ammonia and glutamine levels remained within normal ranges.
- Maternal benzoate infusion shortly before birth was shown to be safe.
Implications:
- Prenatal benzoate administration is a safe and effective strategy for managing UCD in utero.
- This approach can establish therapeutic benzoate levels at birth, potentially mitigating severe neonatal hyperammonaemia and neurological complications.
- Further research can explore optimizing prenatal benzoate dosing and its long-term impact on UCD outcomes.
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