Metabolic Disorders

There are many different types of metabolic disorders, but most are very rare. The most common metabolic condition is phenylketonuria (PKU). Other examples include galactosemia, medium chain acyl-coA dehydrogenase deficiency (MCAD), Prader-Willi syndrome and other disorders of fatty acid utilization.

Metabolic disorders can affect the utilization of protein, fat or carbohydrates or a combination of these. Most are inherited genetic conditions. Metabolic disorders are lifelong conditions, but in general, early treatment can alter their natural progression.

If your child has a metabolic disorder, symptoms may appear only a few days after birth, or they could take years to develop (this is rare). Symptoms may not be evident until the body is stressed by illness or fasting.

The symptoms of metabolic disorders may include:

• Abnormal odor of breath, sweat and urine
• Somnolence (excessive sleepiness)
• Developmental delay
• Failure to thrive (in infants)
• Jaundice
• Lethargy
• Poor appetite
• Seizures
• Vomiting

Diagnosis of Metabolic Disorders

Some metabolic conditions are identified within a few days of a child’s birth through newborn screening tests. These tests use a blood sample to check for treatable disorders, including some metabolic, endocrine, hematologic and respiratory disorders that may not be immediately apparent. If your child’s test shows any abnormal results for the metabolic screening, he or she will need to be evaluated by a doctor within five to seven days.