Seven years of experience with selective screening for organic acidurias.

Between 1975 and 1981 nearly 9000 patients with suspected inherited metabolic diseases were investigated by a selective screening procedure including, apart from simple tests for ketone bodies, sugars and SH-containing compounds, high voltage electrophoresis of amino acids as well as gas liquid chromatography and gas liquid chromatography-mass spectrometry of the organic acids. Fifty-two cases with 18 different inborn errors of metabolism were detected. The effectivity index was calculated to be 0.6% or 1 case in about 170 requests. From the presented and from already existing data in the literature the overall incidences for all organic acidurias together and for propionic acidemia separately were appraised to be 1:10000 and 1:50000, respectively. About half of the patients diagnosed by this screening may benefit from the diagnosis.