A Newborn Infant With Poor Feeding: Non-ketotic Hyperglycinemia

Non-ketotic hyperglycinemia (NKH) is a rare autosomal recessive disorder affecting glycine metabolism that is a rare metabolic disorder in infants. The clinical manifestations of poor sucking, hypotonicity, lethargy, hiccups, and seizures develop within six hours to eight days of the birth of an otherwise healthy newborn. The present study introduced a newborn girl with poor feeding and hypotonia in the first day after birth with NKH. In addition, the patient was evaluated regarding hypotonia and poor feeding. The neonatal-onset NKH was diagnosed based on a markedly elevated cerebrospinal fluid/plasma glycine ratio of 0.32 and confirmed by the genetic test. It is extremely rare that NKH is manifested with poor feeding and hypotonia thus considering this diagnosis in infants with poor feeding and hypotonia is highly important.