**3.1 Transplant listing criteria**

Candidacy for liver transplantation must be determined quickly in the setting of ALF, given the rapid progression of the syndrome. In the US, ALF is one of the few conditions for which a patient can be listed as a United Network for Organ Sharing (UNOS) status 1A (urgent) patient (available at http://www.unos.org) (Table 1). ALF patients may be listed in the "super urgent" category in the United Kingdom. Approximately half of ALF patients undergo liver transplantation; however, ALF accounts for less than 10% of US transplant and 11% in Europe (Freeman et al., 2008; Organ Procurement & Transplantation Network [OPTN], 2009).
