http://www.ncbi.nlm.nih.gov/pubmed/27540711

Raizner A, Shillingford N, Mitchell PD, Harney S, Raza R, Serino J, Jonas MM, Lee CK. J Pediatr Gastroenterol Nutr. 2016 Aug 18.

Abstract

OBJECTIVES:
Transient elastography (TE) measures liver stiffness to assess fibrosis. Studies in adults have shown that inflammation increases stiffness, leading to an overestimation of fibrosis. We investigated the contribution of inflammation to liver stiffness measurements (LSM) in children/ young adults.

METHODS:
This was a cohort analysis of children/ young adults who underwent TE within 1 year of liver biopsy. ALT was obtained within 30d of the biopsy and LSM. Fibrosis was assessed by METAVIR stage and inflammation by ALT and Ishak score. Data were stratified into METAVIR F0-F2 vs. F3-F4. Change between ALT and LSM over time was also assessed.

RESULTS:
154 patients (50% male) age 3wk to 24y (18% <3 years) were studied. Diagnoses included autoimmune (N = 38, 25%), viral (N = 25, 16%), cholestasis (N = 17, 11%), fatty liver (N = 9, 6%), biliary atresia (N = 8, 5%), metabolic (N = 5, 3%), allograft rejection (N = 4, 3%), and other (N = 48, 31%). 34% of patients had F3-F4. In patients with F0-F2, the proportion of those with LSM >8.6kPa increased with increasing ALT (P = 0.002). In patients with F3-F4, there was no association between ALT and LSM (P = 0.17). A correlation between change in ALT and LSM was observed in patients with no/minimal fibrosis and inflammatory liver diseases (r = 0.33).

CONCLUSIONS:
In children with no/minimal hepatic fibrosis and inflammatory liver disease, high ALT values are associated with LSM in the range typical of advanced fibrosis. However, with more advanced fibrosis, inflammation does not appear to contribute to LSM. Caution must be taken when interpreting LSM for assessing fibrosis severity in the setting of inflammation.