Liver Stiffness Norms by SWE in Children: Age-Related Reference Values
Key Principle: Adult Thresholds Are Not Applicable
According to the WFUMB Guideline/Guidance (Ferraioli et al., 2024), the proposed 'rule of four' for adults cannot be applied to the pediatric population. Based on current literature, a value of <5 kPa allows exclusion of fibrosis, whereas a value of >15 kPa indicates progressive liver disease — except in children with biliary atresia (BA), cystic fibrosis liver disease (CFLD), or post-Fontan operation patients.
Age-Related Reference Values (Transient Elastography)
According to the EFSUMB Course Book (Sporea et al., 2018), the average liver stiffness by TE in healthy children was 4.7 kPa. Median values were significantly age-dependent (p = 0.001):
| Age | Median Stiffness (TE), kPa |
|---|---|
| 0–5 years | 4.40 |
| 6–11 years | 4.73 |
| 12–18 years | 5.1 |
These values were obtained using Transient Elastography; specific age references for 2D-SWE / point SWE are not provided in fragments [to be clarified].
Fibrosis Staging
SWE is useful for diagnosing and monitoring chronic liver diseases in children, as well as for assessing clinical outcomes (Recommendation 13, WFUMB 2024; LoE 2a, GoR B, strong consensus 12/0/0, 100%). However, specific thresholds for staging fibrosis in children cannot be recommended due to the heterogeneity of published studies.
Indications for Liver Elastography in Children
According to the EFSUMB Course Book (2018), main indications include assessment of fibrosis in viral hepatitis, NAFLD, cystic fibrosis, biliary atresia, and graft fibrosis post-liver transplantation. A special probe (S-Probe) is used for TE in children. Liver stiffness significantly correlates with the Ishak histological index (r = 0.879, p < 0.0001).
Frequently asked questions
Can the adult 'rule of four' be applied to children?
No. According to WFUMB (2024), the rule of four for adults is not applicable in the pediatric population.
What value excludes fibrosis in a child?
A value <5 kPa allows exclusion of fibrosis (WFUMB, 2024).
What value indicates progressive liver disease?
>15 kPa — except in children with biliary atresia, CFLD, or post-Fontan operation patients (WFUMB, 2024).
Is liver stiffness age-dependent?
Yes. By TE, median values are significantly age-dependent: 4.40 (0–5 years), 4.73 (6–11 years), 5.1 kPa (12–18 years), p=0.001.
Are there recommended thresholds for staging fibrosis in children?
No. Specific thresholds for staging fibrosis in children cannot be recommended due to study heterogeneity (WFUMB 2024, LoE 2a, GoR B).