ARG1 and urea cycle disorder: Agrininemia, or ARG1 deficiency, belongs to a rare autosomal recessive inherited urea cycle disorder, caused by a mutation in ARG1 gene located on chromosome 6 (6q23), which was first reported by Terheggen et al.[3] In our case, the gene test revealed that he carried a compound heterozygous mutation, c.(263-266delAGAA) (p.[K88Rfs∗45]) and c.(647T > C) (p.[L261P]) respectively from his parents.