Is Weight Normalization After Childhood Liver Transplant Fat?

Abstract

Introduction: Growth normalization after liver transplant is a desirable long term outcome in children with chronic liver disease. Weight recovery is usually rapid and often normalizes within a year although height recovery can be prolonged. It is unknown whether this recovery occurs as a result of increased body cell mass. Aims: To assess whether there was improvement in the body cell mass of long term survivors after liver transplant in childhood. Methods: Total body potassium (TBK) measurements to estimate metabolically active body cell mass were performed with a shadow shield whole body counter over a scanning bed. Body cell mass (BCM) was calculated from TBK measurements [BCM (kg) = (TBK*9.18)/39.1], andadjusted for height and gender (males=BCM/Ht3; females=BCM/Ht2.5). Measurements were performed before and after liver transplant. Paired t-tests were used to analyse the data.Results: Pre and post transplant measurements were available in 20 patients. There was no difference in the age of transplant or timing of TBK measurement after transplant between the genders. Body cell mass for height was significantly reduced after transplant in long term survivors (t= 3.83, p=0.00). When analysed according to gender, this was significant for boys (t=6.04, p=0.00)but not girls. Summary/Conclusions: Body cell mass was significantly reduced in long term survivors after liver transplant, especially boys. This implies that fat accumulation is the main reason for weight recovery, which may subsequently predisposethese children to obesity.