Prenatal Diagnosis of Propionic and Methylmalonic Acidaemia by Stable Isotope Dilution Analysis of Amniotic Fluid

Abstract

Stable isotope dilution gas chromatography—mass spectrometry (GC/MS) analysis of methylcitric acid in amniotic fluid for the rapid and accurate prenatal diagnosis of propionic acidaemia (McKusick 23200) and methylmalonic acidaemia (McKusick 25100) was first described in 1980 (Naylor et al., 1980). This was soon followed by similar methods for the determination of methylmalonic acid in amniotic fluid for prenatal diagnosis of methylmalonic acidaemia (Trefz et al.,1981; Zinn et al., 1982; Sweetman et al.,1982). We describe here our results for the prenatal diagnosis of 102 pregnancies at risk for either propionic acidaemia or methylmalonic acidaemia.