Which role remains for selective screening for inborn errors of metabolism in times of newborn screening with tandem mass spectrometry?

For several decades general neonatal screening for inborn metabolic and endocrine disorders through the examination of dried blood spots has been available in Germany and Austria. More recently, this newborn screening has been extended in these two countries to include tandem mass spectrometry analyses. The extended neonatal screening and its potential have rightly attracted major attention, but the heavy emphasis placed on its potential has also made some pediatricians uncertain about the further need for organic acid/amino acid analyses and other assays performed as selective screening tests for inborn errors of metabolism. We therefore give an introduction to routine and selective newborn screening and present signs, symptoms and laboratory data that can prompt selective metabolic screening.