Two cases of glycine encephalopathy accompanied by pes equinovarus.

Glycine encephalopathy is a rare autosomal recessive metabolic disease characterized by glycine accumulation in body fluids owing to a defect in the glycine cleavage system. There are several forms of glycine encephalopathy. In the classic or neonatal form, symptoms usually develop as neurologic symptoms in the first few days of life. It characteristically presents with hypotonia, lethargy, apnea, and seizures and usually results in death by 1 year of age. In this report, we present two cases of neonatal glycine encephalopathy accompanied by isolated pes equinovarus deformity.