Lack of clinical change in longitudinal vibration controlled transient elastography among children with cystic fibrosis and poor association with non-invasive biomarkers of liver disease.

BACKGROUND

Liver stiffness measurement (LSM) has gained interest as a modality to screen for cystic fibrosis hepato-biliary involvement (CFHBI) and monitor for disease progression. Studies of its effectiveness in longitudinal prospective cohorts are lacking.

METHODS

The ELASTIC study evaluated LSM by FibroScan® in children with or without CFHBI. Liver ultrasound (US) and clinical data were collected annually. Changes in LSM were assessed for association with US grade and changes in noninvasive biomarkers of liver disease. Additionally, we evaluated intra-individual variation in LSM measurements utilizing the reliable change index.

RESULTS

There were 96 participants completed longitudinal assessment by FibroScan® with US and laboratory data available within one-year. Nodular (NOD) and normal (NL) US patterns were significantly associated with decrease in LSM (-5.4% and -4.7% respectively), but within expected variability. No association with LSM was observed among heterogenous (HTG) or homogenous (HMG) US patterns. Reliable change index showed large intra-individual variation between FibroScan® examinations with a decrement of 48% through an increment of 93% being within the normal range of expected variation. Changes in LSM were associated (p < 0.001) with clinical variables including GGT (r= 0.64), spleen size z-score (r=0.42), platelets (r=-0.38), and APRI (r=0.34).

CONCLUSION

There is considerable intra-individual variation of LSM by FibroScan® among children with or without CFHBI. We were unable to detect incremental changes in LSM in CFHBI. Significant association between changes in LSM and biomarkers of liver disease were observed. Further exploration is required to determine the clinical utility of LSM in the assessment of CFHBI.