Laboratory analysis of blood spots dried on filter paper for the purpose of screening newborns plays a pivotal role in preventive medicine. Only a few disorders were screened for during its first 30 years of existence. This situation has dramatically changed over the course of the past 10 years since tandem mass spectrometry (MS/MS) was introduced into several newborn screening laboratories worldwide. More than 30 additional disorders can be detected with MS/MS by simultaneous acylcarnitine and amino acid analyses in a single blood spot. These disorders are inborn errors of amino acid, organic acid, and fatty acid metabolism. Most of these present acutely with severe metabolic crises, resulting in severe morbidity and, often, death. The ability to identify affected newborns before the onset of symptoms can dramatically improve the prognosis of most patients. However, MS/MS has not yet found wide acceptance in screening laboratories, because operation and, particularly, data interpretation are complex and require significant user experience. Furthermore, a consensus is lacking as to whether some detectable disorders should be excluded because of limited follow-up capacities within the health care system and limited treatment options. In this review, the history of newborn screening as it pertains to laboratory testing, tandem mass spectrometry, and the current issues regarding the implementation of expanded newborn screening by MS/MS are discussed.
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism