Neonatal screening and rare diseases. From the Guthrie test to mass spectrometry

Abstract

Background: Neonatal screening begins with Phenylketonuria, the first metabolic disease detected by the Guthrie test, a bacterial inhibition test. More diseases are currently screened with tandem mass spectrometry. Neonatal screened diseases vary from country to country, but there is an international consensus on which ones meet world health organization criteria. Colombia adheres to this consensus under the 1980 law of 2019. The pathologies subject to neonatal screening are defined in basic screening and expanded screening, which includes innate errors of amino acids and organic acids metabolism. Most of them are disorders in the beta-oxidation of fatty acids. Theme: Although much goes from Guthrie's test to Tandem Mass Spectrometry, and there are advances in the screening of congenital hypothyroidism, the current challenge is to have laboratories capable of responding to the diagnosis of Rare Diseases and particularly neonatal screening. Most rare diseases have genetic etiology, which is reflected in the molecular diagnostic and follow-up tests, the standard Gold test. Only some of the Rare Diseases are subject to neonatal screening, requiring tests distributed between molecular genetic tests and complex biochemical tests, both instrumental and enzymatic. Conclusions: The Clinical Laboratory may do the initial tests of Neonatal Screening, but the confirmatory and follow-up tests are complex and require confluence in networks from different specialized laboratories.