Review and clinical update on parenteral nutrition-associated liver disease.

Parenteral nutrition-associated liver disease (PNALD) is a complex disease that is diagnosed by clinical presentation, biochemical markers of liver injury, concurrent use of parenteral nutrition (PN), and negative workup for other causes of liver disease. Since the first case of PNALD was reported more than 30 years ago, clinicians have had few effective treatments for PNALD, and when disease progressed to liver cirrhosis, it was historically associated with poor outcomes. Within the past 5 years, there has been much excitement about new treatments for PNALD, including use of both parenteral and enteral ω-3 polyunsaturated long-chain fatty acids (ω-3 PUFA) as well as restricting dosing of ω-6 PUFA. Scientists are also interested in uncovering the mechanisms associated with liver injury seen in PNALD. This article reviews the recent literature relating to the pathophysiology and treatment of PNALD.