NEONATAL SCREENING FOR INHERITED METABOLIC DISEASES

Routine screening of newborn infants for metabolic disorders was introduced in 1961 after Bickel established an effective dietary therapy for phenyketonuria (PKU) and Guthrie developed a bacterial inhibition assay to detect elevated concentrations of phenylalanine in dried blood tests. Over time, neonatal screening has been expanded to several other treatable metabolic and endocrine disorders, including galactosemia, biotinidase defi ciency, congenital hypothiroidism, congenital adrenal hyperplasia. A major step in recent years has been the development of routine acylcarnitine and aminoacid analysis in guthrie cards by tandem mass spectroscopy. Researchers at Duke University developed tandem mass spectroscopy of acylcarnitines and aminoacids for expanded newborn screening in the early 1990’s. It allows for screening aminoacidopathies, including PKU, organic acidurias and disorders of fatty acids oxidation. A positive result often constitutes a metabolic emergency as infants with many of the disorders diagnosed bz the technique can become critically ill in the fi rst days after birth