Effects of Infliximab and Parenteral Nutrition on Albumin and Fibrinogen Synthesis Rates in Pediatric Crohn Disease

Abstract

Tumor necrosis factor-alpha (TNF-alpha) may play a significant role in growth disturbance in pediatric Crohn disease. The aim of this study was to determine the effects of anti-TNF-alpha therapy on albumin and fibrinogen synthesis during both fasting and parenteral nutrition infusion in pediatric patients with active Crohn disease. Children with active Crohn disease scheduled for their initial dose of infliximab underwent assessment immediately before and 2 weeks following infliximab infusion. Using the stable isotope [d5] phenylalanine, rates of fractional and absolute albumin and fibrinogen synthesis were calculated. Measurements were made in both the fasting and parenterally fed states. Fifteen children (mean age 14.9 +/- 0.3) completed the study. The mean serum albumin changed from 3.59 +/- 0.08 to 3.66 +/- 0.04 g/dL, and the mean fibrinogen level decreased from 230 +/- 17 to 187 +/- 8 mg/dL (P < 0.05) following infliximab therapy. During fasting, there were no changes in albumin and fibrinogen synthesis rates following infliximab. During parenteral nutrition infusion, the fractional albumin synthesis rate changed from 11.8% to 15.1%/day (P = 0.06), and the absolute albumin synthesis rate increased from 192 to 248 mg x kg(-1) x day(-1) (P < 0.05), whereas no changes in fibrinogen synthesis rates were observed. Synthesis rates of albumin and fibrinogen were increased during parenteral nutrition infusion compared with the fasting state. Following infliximab therapy, during parenteral nutrition infusion, albumin synthesis increased significantly. Conversely, serum fibrinogen levels decreased following infliximab therapy in the absence of significant change in synthesis rates.