ABSTRACT
3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) lyase deficiency is a rare inborn error of metabolism characterized by recurrent metabolic crises caused by fasting, intercurrent illness and excessive physical exercise. Non ketotic hypoglycemia is normally the cause of primary symptoms but without an immediate treatment the illness can evolve into a worsening metabolic state resembling the Reye's syndrome that may cause the patient's death. We report a neonate with some clinical and therapeutic features not previously described mutation in HMGCL gene. The genetic analysis revealed a novel homozygous c.272T>A(p.Val91Asp) mutation in HMGCL gene. HMG-CoA lyase deficiency should be thought in the patients with hypoketotic hypoglycemia, hyperammonemia, elevated liver function tests and metabolic acidosis.