Effects of infliximab and parenteral nutrition on albumin and fibrinogen synthesis rates in pediatric Crohn disease.

OBJECTIVES: 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. PATIENTS AND METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.