Indocyanine green clearance's association with liver function in paediatric liver disease

Aim: Indocyanine green (ICG) clearance, a sensitive biomarker for liver function, has not been validated in children. We assessed the association between ICG clearance and liver function in children with liver disease. Methods: ICG plasma disappearance rate (ICG-PDR, %/min) was measured in children with liver disease. Mixed linear regression was used to assess the relationship between ICG-PDR and liver function tests (international normalised ratio, INR; prothrombin-proconvertin clotting time, PP). Results: We included 124 patients with 183 visits. Of the visits, 60.1% were female, 85% had chronic liver disease and 42.5% were liver transplanted. The most common diseases in those without transplantation were autoimmune disease (18.6%) and biliary atresia (10.9%). Median ICG-PDR was 23.9%/min (interquartile range 15; 30.3). Mixed linear regression showed ICG-PDR was associated with INR (β = −0.006, 95% CI [−0.010, −0.003]) and PP (β = 0.005, 95% CI [0.003, 0.008]). However, only five visits were with patients who had acute liver failure (INR ≥2.0). Conclusion: ICG clearance is associated with standard measures of liver function in children. ICG may aid decision-making in paediatric liver disease together with other biochemical measures, imaging and clinical presentation. However, further studies are needed to assess the usefulness of ICG in paediatric patients with INR >1.4.