Pathogenesis and treatment of parenteral nutrition-associated liver disease

Zi-Wei Xu and You-Sheng Li
Nanjing, China

BACKGROUND: Parenteral nutrition-associated liver disease
(PNALD) has been common in patients who require long-term
parenteral nutrition. PNALD develops in 40%-60% of infants
on long-term parenteral nutrition compared with 15%-40% of
adults on home parenteral nutrition for intestinal failure. The
pathogenesis of PNALD is multifactorial and remains unclear.
There is no specific treatment. Management strategies for its
prevention and treatment depend on an understanding of
many risk factors. This review aims to provide an update on the
pathogenesis and treatment of this disease.
DATA SOURCES: A literature search was performed on the
MEDLINE and Web of Science databases for articles published
up to October 2011, using the keywords: parenteral nutrition
associated liver disease, intestinal failure associated liver disease,
lipid emulsions and fish oil. The available data reported in the
relevant literatures were analyzed.
RESULTS: The literature search provided a huge amount of
evidence about the pathogenesis and management strategies
on PNALD. Currently, lack of enteral feeding, extended
duration of parenteral nutrition, recurrent sepsis, and
nutrient deficiency or excess may play important roles in the
pathogenesis of PNALD. Recent studies found that phytosterols,
present as contaminants in soy-based lipid emulsions, are
also an important factor in the pathogenesis. Moreover, the
treatment of PNALD is discussed.
CONCLUSIONS: The use of lipid emulsions, phytosterols
in particular, is associated with PNALD. Management
strategies for the prevention and treatment of PNALD include
consideration of early enteral feeding, the use of specialized
lipid emulsions such as fish oil emulsions, and isolated small
bowel or combined liver and small bowel transplantation. A
greater understanding of the pathogenesis of PNALD has led to promising interventions to prevent and treat this condition.
Future work should aim to better understand the mechanisms
of PNALD and the long-term outcomes of its treatment.
(Hepatobiliary Pancreat Dis Int 2012;11:586-593)