Worsening of Seizures After Asparagine Supplementation in a Child with Asparagine Synthetase Deficiency.
Asparagine synthetase deficiency is an autosomal recessive neurometabolic disorder characterized clinically by severe congenital microcephaly, global developmental delay, intractable epilepsy, and motor impairment in the form of spastic quadriparesis. Diagnosis is confirmed by findings of low cerebral spinal fluid or plasma asparagine in addition to a mutation of the subsequently in ASNS gene. There is no documented trial of asparagine as a treatment for this disorder.



We present a child with asparagine synthetase deficiency whose mental status improved slightly from a vegetative state to a minimally conscious state after starting asparagine supplementation. He subsequently became irritable, developed sleep disturbance, and experienced worsening seizures, requiring discontinuation of the asparagine supplements.



Asparagine supplementation may be not effective in controlling the seizures in asparagine synthetase deficiency, and it is likely to make them worse.
Division of Neurology, Department of Pediatrics, King Abdulaziz Medical City, Riyadh, Saudi Arabia; King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Riyadh, Saudi Arabia. Electronic address: RifaiM@ngha.med.sa.
Muhammad Talal
MT
Alrifai
King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Riyadh, Saudi Arabia; Division of Genetics, Department of Pediatrics, King Abdulaziz Medical City, Riyadh, Saudi Arabia. Electronic address: dralfadhelm@gmail.com.
Majid
M
Alfadhel
D001216:Asparagine / Q000009:adverse effects* / Q000627:therapeutic use; D001217:Aspartate-Ammonia Ligase / Q000172:deficiency* / Q000235:genetics; D002491:Central Nervous System Agents / Q000009:adverse effects* / Q000627:therapeutic use; D002675:Child, Preschool; D006801:Humans; D008297:Male; D012640:Seizures / Q000235:genetics / Q000503:physiopathology*; D012720:Severity of Illness Index; D017211:Treatment Failure
D002491:Central Nervous System Agents; D001216:Asparagine; D001217:Aspartate-Ammonia Ligase
ASD; asparagine; asparagine synthetase deficiency; inborn errors of metabolism; l-asparagine; neurometabolic