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. 2018 Jul 5;18(1):215.
doi: 10.1186/s12887-018-1202-z.

Normal serum alanine aminotransferase and non-alcoholic fatty liver disease among Korean adolescents: a cross-sectional study using data from KNHANES 2010-2015

Yunkoo Kang  1 , Sowon Park  1 , Seung Kim  1 , Hong Koh  2
Affiliations

Normal serum alanine aminotransferase and non-alcoholic fatty liver disease among Korean adolescents: a cross-sectional study using data from KNHANES 2010-2015

Yunkoo Kang et al. BMC Pediatr. .

Abstract

Background: Non-alcoholic fatty liver disease (NAFLD) is complicated disease and increasing worldwide. Previously, many studies of NALFD prevalences have used alanine aminotransferase (ALT) of > 40 U/L to define NAFLD, although that is too high to be reliable among adolescents. This study aimed to define the upper normal limit of ALT among Korean adolescents, and use it to estimate the prevalence of NAFLD, based on data from the Korea National Health and Nutrition Examination Survey (KNHANES).

Methods: Data were obtained from 1785 healthy adolescents (916 boys and 869 girls, 10-18 years old) who participated in the KNHANES during 2010-2015. The International Diabetes Federation metabolic syndrome criteria for adolescents were used to exclude participants with metabolic syndrome components. Furthermore, participants who previously had diseases related to low HDL levels, high TG levels, diabetes, or very low/high body mass index and hepatitis B were excluded. The 95th percentiles level of ALT from healthy participants were evaluated. The definition of NAFLD was overweight status (≥85th percentile of body mass index) plus elevated ALT levels (95th percentile).

Results: The upper normal ALT were 24.1 U/L for boys and 17.7 U/L for girls. Based on these values, the estimated prevalences of NAFLD in 2015 were 8.9% among adolescents.

Conclusion: Defining the upper normal limit of ALT can be adjusted for each sex and ethnics in the general population. ALT laboratory thresholds used for children should be re-examined. The physicians should be aware not to underdiagnose NAFLD patient even ALT level is < 40 U/L.

Keywords: Alanine aminotransferase; Korea; Non-alcoholic fatty liver disease; Upper normal limit.

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Conflict of interest statement

Ethics approval and consent to participate

The KNHANES surveys (http://knhanes.cdc.go.kr/) are approved by the Korean Center for Disease Control (2010-02CON-21-C, 2011-02CON-06-C, 2012-01EXP-01-2C, 2013-07CON-03-4C, 2013-122EXP-03-5C, and 2015–01-02-6C), and all participants provide written informed consent.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
Flow chart for participant selection (916 boys, 869 girls)
Fig. 2
Fig. 2
Trends in the 95th percentiles for alanine aminotransferase (a) and the prevalence of participants with elevated alanine aminotransferase (>95th percentile) (b)
Fig. 3
Fig. 3
The estimated prevalence of non-alcoholic fatty liver disease among Korean adolescents
See this image and copyright information in PMC

References

    1. Suchy FJ, Sokol RJ, Balistreri WF. Liver disease in children, 4th edn. Cambridge. New York: Cambridge University Press; 2014.
    1. Oh H, Jun DW, Saeed WK, Nguyen MH. Non-alcoholic fatty liver diseases: update on the challenge of diagnosis and treatment. Clin Mol Hepatol. 2016;22(3):327–335. doi: 10.3350/cmh.2016.0049. - DOI - PMC - PubMed
    1. Janczyk W, Socha P. Non-alcoholic fatty liver disease in children. Clin Res Hepatol Gastroenterol. 2012;36(3):297–300. doi: 10.1016/j.clinre.2012.03.026. - DOI - PubMed
    1. Kim WR, Flamm SL, Di Bisceglie AM, Bodenheimer HC. Public policy Committee of the American Association for the study of liver D: serum activity of alanine aminotransferase (ALT) as an indicator of health and disease. Hepatology. 2008;47(4):1363–1370. doi: 10.1002/hep.22109. - DOI - PubMed
    1. Prati D, Taioli E, Zanella A, Della Torre E, Butelli S, Del Vecchio E, Vianello L, Zanuso F, Mozzi F, Milani S, et al. Updated definitions of healthy ranges for serum alanine aminotransferase levels. Ann Intern Med. 2002;137(1):1–10. doi: 10.7326/0003-4819-137-1-200207020-00006. - DOI - PubMed

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