Hepatic Dry Copper Weight in Pediatric Autoimmune Liver Disease

Elevated hepatic dry copper weight is recognized in adults with autoimmune liver disease (AILD) and chronic cholestasis. We aim to review hepatic dry copper weight in pediatric AILD.

Retrospective review of pediatric AILD managed at our institution from 1999 to 2018, and 104 patients with hepatic dry copper weight assessment were included.

Median age at presentation was 13.4 years (interquartile range, IQR, 11.7-14.9), 60% female, 54% autoimmune hepatitis, 42% autoimmune sclerosing cholangitis, and 4% primary sclerosing cholangitis. Histological features of advanced liver fibrosis in 68%. Median hepatic dry copper weight was 51.1 µg/g dry weight (IQR, 28.0-103.8). Elevated hepatic dry copper weight (>50 µg/g dry weight) was present in 51%, and was not associated with AILD subtype ( P = 0.83), age at presentation ( P = 0.68), or advanced fibrosis ( P = 0.53). Liver transplantation (LT) was performed in 10%, who had higher hepatic dry copper weight (148.5 µg/g dry weight [IQR, 39.5-257.3] vs 47.5 [IQR, 27.8-91.5], P = 0.04); however this was not associated with LT on multivariate analysis (hazard ratio 1.002, 95% CI 0.999-1.005, P = 0.23). In 8 (7.7%) patients ATP7B was sequenced and potentially disease causing variants were identified in 2 patients, both who required LT.

Elevations in hepatic dry copper weight are common in pediatric AILD. Unlike in adults, it is not associated with AILD subtypes with cholestasis. Higher dry copper weight was detected in patients who required LT. While further work is needed to identify the significance of copper deposition in pediatric AILD, we recommend close monitoring of patients with elevated levels for progressive liver disease.