Application and Limitations of Transient Liver Elastography in Children

Objectives:Transient elastography (TE) using the FibroScan has gained popularity recently for the noninvasive diagnosis of hepatic fibrosis. Data on its use in children younger than 6 years are still scarce, and the influence of technical aspects such as probe choice and site of measurement on FibroScan results is not clear. Our study aims to clarify some technical issues concerning the use of the FibroScan in children and to deliver normal FibroScan values for reference.Methods:TE was performed in 527 children (229 girls, ages 0.1-17.8 [median 6.0] years, including 400 healthy controls). Feasibility of different sites of measurements, paired comparison of probe settings, and pre- and postprandial measurements were systematically performed. Sedated versus unsedated measurements were compared in age- and sex-matched cohorts.Results:Success rate of TE in our population was 90%, but decreased to 83% in children younger than 24 months even in ideal conditions. General anesthesia significantly increased liver stiffness in healthy children (5.4 [3-9.5] vs 4.2 [2.8-8.15] kPa; P<0.01). Probe choice equally influenced results in paired comparisons (S1 5.5 [3.5-17.9] vs S2 4.8 [2.1-15.4] kPa; P<0.01), as did food intake (5.9 [3.6-75] vs 5.4 [3.6-63.9] kPa; P=0.015). Inter- and intraobserver agreements were good. Normal liver stiffness was 4.5 (2.5-8.9) kPa and did not vary significantly with age or sex.Conclusions:TE is feasible even in extremely young children, but confounding influences on test results such as probe choice, sedation, or food intake need to be taken into account when interpreting results.