What are inherited metabolic disorders?

Inherited metabolic disorders — also known as inborn errors of metabolism — are heritable, or genetic, disorders. There are hundreds of known inborn errors of metabolism, including albinism, cystinuria and phenylketonuria (PKU).

Symptoms

In young infants, symptoms include apnea, lethargy, poor feeding, tachypnea and vomiting.

Diagnosis

Advances in the diagnosis and treatment of inborn errors of metabolism have improved the outlook for many of these conditions. Laboratory testing for metabolic disorders includes tests for:

• Hypoglycemia, or low blood sugar, which is the predominant finding in a number of inborn errors of metabolism
• Jaundice or other evidence of liver disease, a sign of another important group of inborn errors of metabolism

Treatment

In the last two decades, enzyme replacement, gene transfer and organ transplantation have shown benefit for many previously untreatable inborn errors of metabolism.