Neonatal screening by tandem mass spectrometry: an update

Tandem mass spectrometry (MS/MS) has made it possible to expand neonatal screening programs in different countries. This technology permits multiple and rapid diagnosis of diverse inborn errors of metabolism. However, its use in different programs around the world currently varies widely. There are different criteria for determining whether to include a specific disease in such programs, with some cases employing a more restrictive approach than others, based on the traditional screening principles enunciated by Wilson and Jungner, which will have to be reevaluated in light of this new technology. This article presents an update on the use of MS/MS in different regions of the world in terms of the diseases screened for, and the criteria for including new health problems in neonatal screening programs.