Organic acidemias in Korea

Lee, Hong Jin

Abstract

Since we started organic acid analysis in July 1997, we have collected data about organic acidemias in Korea. The data presented herein constitute our 3 years experience in organic acid analysis. We have collected 712 samples from major university hospitals in all over Korea, which are large enough for relatively accurate estimation of incidence of organic acid disorders. We used solvent extraction method with ethylacetate, MSTFA for derivatization and simultaneously quantitation of 83 organic acids. Out of 712 patients sample, 498 samples (70%) showed no evidence of organic acid abnormalities. Out of the 214 remaining samples, we found very diverse disorders such as methylmalonic aciduria (6), propionic aciduria (10), biotinidase deficiency (6), maple syrup urine disease (3), isovaleric aciduria (4), tyrosinemia type II (4), tyrosinemia type IV (1), glutaric aciduria type I (1), glutaric aciduria type II (22), 3-methylglutaconic aciduria type I (3), 3-methylglutaconic aciduria type III (7), HMG-CoA lyase deficiency (1), hyperglyceroluria (2), cytosolic 3-ketothiolase deficiency (55), mitochondrial 3-ketothiolase deficiency (3), 3-hydroxyisobutyric aciduria (2), L-2-hydroxyglutaric aciduria (2), fumaric aciduria (2), lactic aciduria with combined elevation of pyruvate (most likely PDHC deficiency) (28), lactic aciduria without combined elevation of pyruvate (most likely mitochondrial respiratory chain disorders) (35), SCAD deficiency (3), MCAD deficiency (1), 3-methylcrotonylglycineuria (1), orotic aciduria (most likely urea cycle disorders) (7) and 2-methylbranched chain acyl-CoA dehydrogenase deficiency (1). In conclusion, although the incidence of individual organic acidemia is low, the incidence of overall organic acidemia is relatively high in Korea. Most of the patients showed some signs of neurological dysfunction. Therefore, organic acid analysis should be included in the diagnostic work up of all neurological dysfunctions.