Effects of early enteral nutrition on immune function of severe acute pancreatitis patients

AIM: To investigate the effects of early enteral nutrition (EEN) on the immune function and clinical outcome of patients with severe acute pancreatitis (SAP). METHODS: Patients were randomly allocated to receive EEN or delayed enteral nutrition (DEN). Enteral nutrition was started within 48 h after admission in EEN group, whereas from the 8(th) day in DEN group. All the immunologic parameters and C-reactive protein (CRP) levels were collected on days 1, 3, 7 and 14 after admission. The clinical outcome variables were also recorded. RESULTS: Sixty SAP patients were enrolled to this study. The CD4+ T-lymphocyte percentage, CD4+/CD8+ ratio, and the CRP levels in EEN group became significantly lower than in DEN group from the 7(th) day after admission. In contrast, the immunoglobulin G (IgG) levels and human leukocyte antigen-DR expression in EEN group became significantly higher than in DEN group from the 7(th) day after admission. No difference of CD8+ T-lymphocyte percentage, IgM and IgA levels was found between the two groups. The incidences of multiple organ dysfunction syndrome, systemic inflammatory response syndrome, and pancreatic infection as well as the duration of intensive care unit stay were significantly lower in EEN group than in DEN group. However, there was no difference of hospital mortality between the two groups. CONCLUSION: EEN moderates the excessive immune response during the early stage of SAP without leading to subsequent immunosuppression. EEN can improve the clinical outcome, but not decrease the hospital mortality of SAP patients.