Acute Liver Failure Study Group 13C-Methacetin Breath Test for the Prediction of Outcome in Acute Liver Failure

All sites are expected to participate in the ancillary clinical trials associated with the ALFSG network: 1) the 13C-Methacetin breath test (MBT) trial, evaluating a promising method of determining prognosis for patients with ALI and ALF; For any patient enrolled in the overall ALFSG Registry, the site-PI will also be expected to consider enrollment in each in the MBT trial depending upon specific inclusion and exclusion criteria. The MBT will require separate consent and additional coordinator time for patient management and overall management of the testing process, as well as data collection and transmission to the DCU.