Quantification of Age-related Reference Values for Urinary Organic Acids in the Healthy Korean Population

Choi, Yong Jae; Kim, In Cheol; Choi, You Kyoung; Lee, Hong Jin; Kim, Bong Sung; Park, Won Il; Lee, Kyoung Ja; Giudic, T.; Blaskovics, M.

Original Article

Journal of the Korean Pediatric Society 2001;44(12):1413-1423.
Published online December 15, 2001.

Quantification of Age-related Reference Values for Urinary Organic Acids in the Healthy Korean Population

Yong Jae Choi¹, In Cheol Kim¹, You Kyoung Choi¹, Hong Jin Lee¹, Bong Sung Kim¹, Won Il Park¹, Kyoung Ja Lee¹, T. Giudic², M. Blaskovics²

¹Department of Pediatrics, College of Medicine, Hallym University, Chunchon
²Metabolic Laboratory, Kayser Permanante, CA., USA

한국인의 연령에 따른 소변 유기산의 정상값

최용재^¹^, 김인철^¹^, 최유경^¹^, 이홍진^¹^, 김봉성^¹^, 박원일^¹^, 이경자^¹^, T. Giudici^²^, M. Blaskovics^²

^¹한림대학교 의과대학 소아과학교실
^²Metabolic Laboratory, Kayser Permanante, CA., USA

Abstract

Purpose
: For the accurate diagnosis of organic acidopathies, quantification of urinary organic acid should be done and we should know the normal ranges of each organic acid excreted in the urine. The amount of organic acids excreted in the urine shows wide variability according to ethnic group, diet and age. We have quantified 82 organic acids to make a Korean reference value.
Methods
: Organic acid concentrations were quantified with gas chromatography and the individual acids identified with mass spectrometry in urine specimens from members of the healthy Korean population of ages of one day to more than 12 years, subdivided into four age groups : neonatal period(-2 mon), infantile period(-2 year), childhood period(-12 year) and adolescent and adulthood( over 12 years). For isolation of organic acids from urine, we used solvent extraction method with ethylacetate. Derivatization was done with MSTFA(N-methyl-N-trimethylsilylfluoroacetamide). The library and four points quantification curve for the quantification of each organic acid that we used have been developed by Dr. Giudici of Kayser Permanante Metabolic Laboratory, CA., USA.
Results
: Quantitative ranges and frequency distribution patterns of urinary organic acid excretion are reported, as a basis on which to compare results obtained for patients whose clinical condition suggests that their excretion values may be abnormal.
Conclusion
: The quantitative values we observed, enable the relative significance of different urinary metabolites to be assessed.

Key Words: Korean reference values, Urinary organic acids, Quantification