Acute-On-Chronic Liver Failure: Applying the PIRO Concept

Abstract

Acute-on-chronic liver failure (ACLF), a clinical syndrome associated with a dismal prognosis, occurs acutely in previously stable cirrhotic patients. An important feature of this syndrome is the potential for reversibility if it is recognised early and supportive measures are instituted before multi-organ failure ensues. In response, there have been recent efforts to better define and understand the pathophysiological basis of the condition so as to aid early diagnosis and management. The PIRO concept is conceptually useful as it indicates a distinction between the insult and the response. Interventions that target inflammation may adversely impact on the ability to control the infection, and interventions that target infection may not be useful if pathophysiological process is being driven through inflammation. A classification based on the PIRO concept may allow the categorisation of patients into distinct pathophysiologic and prognostic groups and allow a multidimensional definition of ACLF.