Urea cycle disorders (UCDs) are among the most common inborn errors of liver metabolism. With early diagnosis and improved treatments, the survival of individuals with UCDs has improved, and this improved survival has led to unmasking of some long-term complications such as hepatic dysfunction and progressive fibrosis in a subset of patients. Hepatic complications in UCDs are quite variable and dependent upon the specific metabolic defect.~Currently, there are no guidelines for monitoring hepatic complications or extent of liver disease in UCDs. The gold standard for staging of fibrosis or confirming cirrhosis has traditionally been liver biopsy, an invasive procedure with inherent risks, particularly in the setting of a UCD and compromised coagulation. Recently, non-invasive serum and imaging-based biomarkers have been introduced to assess hepatic fibrosis in adults and children who are at increased risk. Utilization of these technique in individuals with UCDs could be invaluable in both the research and clinical arenas.~The purpose of this study is:~1) To assess risk for increased fibrosis using serum biomarkers and/or VCTE in distal disorders (ASS1D, ASLD and ARG1D) as compared to OTCD 2 ) To assess risk for hepatic fibrosis (liver stiffness as measured by MRE) in individuals with UCDs who have abnormal serum biomarkers and/or VCTE as those who have normal values
This is a multi-center, cross-sectional study to assess risk for liver fibrosis and hepatic injury in individuals with urea cycle disorders (UCDs) using serum biomarkers, Fibroscan, and MRE. This study will be conducted at 5 sites of the Urea Cycle Disorders Consortium: Baylor College of Medicine in Houston, TX, Seattle Children's Hospital in Seattle, WA, Children's Hospital Colorado in Aurora, CO, Children's Hospital of Philadelphia in Philadelphia, PA, and Children's National Medical Center in Washington D.C.