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). 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). 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. 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.

Kang Y, et al. J Korean Med Sci. 2018 Mar;33(14):e109. https://doi.org/10.3346/jkms.2018.33.e109

Objectives: With the introduction of smaller probes (S1, S2), the use of transient elastography has been expanded to children. Accordingly, we aimed to address points of consideration in probe choice and interpretation of measured liver stiffness by applying and comparing FibroScan S and M probes in biliary atresia.Methods: Using S1, S2, and M probes, 3 liver stiffness measurements, success rates, and interquartile ranges were obtained from 100 patients. Patients were assigned to 2 groups according to thoracic perimeter (≤45 cm vs >45 cm). In both groups, obtained values were compared and the relation between liver stiffness measurement and aspartate aminotransferase‐to‐platelet ratio index was analyzed.Results: In the small‐thorax group, the success rate was highest with the S1 probe and the intraclass correlation coefficient (ICC) was highest for S1 versus S2 (0.98), compared with that for S1 versus M (0.69) and S2 versus M (0.77). In the large‐thorax group, ICC was the highest for S2 versus M (0.88), compared with that for S1 versus S2 (0.69) and S1 versus M (0.51). In the small‐thorax group, correlations between aspartate aminotransferase‐to‐platelet ratio index and liver stiffness measurement were stronger for S1 (0.65) and S2 (0.64) than for M (0.49). In the large‐thorax group, all probes showed good correlation, S1 (0.68), S2 (0.62), and M (0.62).Conclusions: We recommend that the S1 probe is more appropriate for use in small children, especially those with a thorax perimeter of 45 cm.

To analyze the effect of short-term supportive temporary partial enteral nutrition therapy for treating severe pediatric Crohn's disease (CD). We conducted a prospective, open-label study in pediatric patients with CD (n=78) from January 2007 to December 2011. The CD patients were divided into three groups according to disease severity (mild, moderate, and severe). Seventeen patients with severe CD received short-term partial enteral nutrition (SPEN) in addition to their general diet for 4 weeks after the induction of remission with medical treatment. This SPEN group was further divided into two groups by age (<13 years, ≥13 years). Nutritional parameters and Pediatric Crohn's Disease Activity Index scores were analyzed at the initial enrollment and following 1 year of treatment for all groups. Nutritional status improved substantially after 1 year of treatment in the severe CD group. Nutritional status in the SPEN group improved considerably more than that in the non-SPEN group. Additionally, the <13-year-old group demonstrated better nutritional status improvement than the ≥13-year-old group. SPEN may be effective in pediatric patients with severe CD for improving nutritional status and moderating disease severity.

It has been known that vitamin D level (serum 25[OH]D) has correlation with inflammatory bowel disease (IBD). The purpose of this study is to investigate changes of serum 25[OH]D in pediatric IBD patients according to the disease activity. A total of 96 children and adolescent with IBD were enrolled in this retrospective study. Serologic inflammatory markers and clinical disease activity scores of the patients were collected, and their correlations with serum 25[OH]D were analyzed. Seasonal variations of serum 25[OH]D were also investigated both in active disease state and remission state. Of the 96 patients, 41 (43%) were women and patients with a vitamin D deficiency (< 20 ng/mL) at diagnosis were 77 (80.2%). There was no significant difference between Crohn's disease and ulcerative colitis for serum 25[OH]D. Serum 25[OH]D was higher in remission group than in active disease group (12.4 [8.8-29] ng/mL vs. 17.9 [12.3-34.4] ng/mL; P < 0.001) and the difference was more significant than other micronutrients. There was no significant difference in serum 25[OH]D concentration between patients with ileal involvement and patients without ileal involvement. There were seasonal variations in the active phase, but there was no significant difference by season in the remission phase. Serum 25[OH]D is inversely correlated with disease activity in IBD. Monitoring and supplementation is required especially for active disease status and in winter and spring season.