Fontan-associated liver disease (FALD) is a serious complication related to the chronically elevated venous pressure and low cardiac output of this abnormal circulation. However, diagnostic markers for this condition are limited. We hypothesized that specific tests for fibrosis developed for other chronic liver diseases would identify a higher prevalence of FALD than ultrasound and standard laboratory tests and that identified abnormalities would correlate with time post-Fontan. In this cross-sectional study, we assessed 19 children (average age 8.4 ± 4.3 and 5.4 ± 4.1 years post-Fontan) and 8 adults (average age 31.5 ± 8.9 and 21.1 ± 4 years post-Fontan) using standard serum laboratory investigations assessing hepatic integrity and function, the FibroTest, liver ultrasound, and transient elastography (FibroScan). In adult Fontan patients, hemoglobin, C-reactive protein, and gamma-glutamyl transpeptidase were significantly increased, and white blood cell and platelet counts were significantly decreased in comparison to the pediatric cohort. International normalized ratio was mildly elevated in both children and adults. FibroTest results were suggestive of fibrosis regardless of time post-Fontan. FibroScan measurements were significantly correlated with time post-Fontan, but the incidence of ultrasound-detected liver abnormalities was variable. No cases of hepatocellular carcinoma were identified. Abnormalities suggestive of FALD occur in both children and adults post-Fontan. Select laboratory tests, and possibly ultrasound and FibroScan in some patients, appear to have the most promise for the non-invasive detection of FALD.

BACKGROUND: Fontan-associated liver disease (FALD) is increasingly recognized as a serious complication post-Fontan resulting from the chronically elevated venous pressure created by this abnormal circulation. This study was designed to: define the prevalence and severity of FALD in our local population of pediatric (age <18 years) and adult Fontan patients, identify useful non-invasive screening tests for FALD and develop a longitudinal surveillance strategy. We hypothesized that severity of injury and fibrosis would correlate with time post-Fontan and that specific tests for fibrosis (including transient elastography, performed using FibroScan, and FibroTest, a score shown to correlate with the degree of liver fibrosis in viral hepatitis, calculated using ALT, GGT,