Body composition assessment after pediatric liver transplant.

BACKGROUND: Pediatric liver transplantation generally restores metabolic function; yet after transplantation, some children remain malnourished, have increased adiposity, and develop obesity. Measurement of body composition in the assessment of nutrition status could reduce adverse consequences in children. METHODS: Anthropometric measurements, multiple-frequency bioelectrical impedance analysis, air displacement plethysmography, and ultrasound measurements were conducted on children recruited from the liver transplant program at the University of Minnesota Masonic Children's Hospital. A cross-sectional study was conducted to describe the quality of weight gain in post-liver transplant children between the ages of 2 and 17 years using multiple assessment tools (air displacement plethysmography, multiple-frequency bioelectrical impedance analysis, and ultrasound) and to determine whether multiple-frequency bioelectrical impedance analysis and ultrasound accurately describe body composition and quality of weight gain. RESULTS: Mean percent body fat by air displacement plethysmography and multiple-frequency bioelectrical impedance analysis was 18.4% (±3.3) and 19.0% (±3.9), respectively (P > .99). There were insufficient data to examine the relationship between summed muscle and adipose thickness measures by ultrasound and percent body fat determined by air displacement plethysmography or multiple-frequency bioelectrical impedance analysis. CONCLUSION: Percent body fat, fat mass, and fat-free mass measures determined by air displacement plethysmography and multiple-frequency bioelectrical impedance analysis were not statistically different, which suggests the stand-on device used in this study could be a useful body composition assessment tool for the pediatric population.

Body Composition Post Pediatric Liver Transplant: Implications and Assessment.

Liver disease has a negative influence on growth and development of children. Measurement of body composition as a component of nutrition status assessment in children before and after transplant would facilitate tailoring of nutrition therapy. A comprehensive literature search on pediatric liver transplant and body composition assessment was performed using a modified systematic approach. This review includes evidence specific to body composition of children undergoing liver transplant and a discussion of relevant body composition assessment methods for this population. Malnutrition is commonly seen in children with liver disease prior to transplant because of the disrupted metabolic pathways from liver dysfunction; however, malnutrition is not consistently diagnosed. Within 1 year of transplant, children tend to quickly recover with weight gain and linear growth. In some children, obesity and sarcopenia have been observed as long-term posttransplant outcomes. Body composition assessment tools have been utilized in diagnosing nutrition status in adults; yet there are limited studies that use these tools in the pediatric liver-transplant population. Technologies available to assess body composition include air displacement plethysmography, dual-energy x-ray absorptiometry, bioimpedance, and ultrasound. Total body potassium has been used for body composition assessment in adults and children post liver transplant; however, this method is not applicable in a clinical setting. We conclude that understanding posttransplant body composition could help clinicians diagnose and treat malnutrition.