Objective: The aim of this study was to investigate the effect of high-volume hemofiltration (HVHF) on ameliorating immune dysfunction in patients with severe acute pancreatitis (SAP).
Methods: Twelve patients diagnosed with SAP admitted to the intensive care unit of general surgery, Jinling Hospital, from January 2004 to December 2006 were included in this study. They were assigned to the standard medical therapy group (SMT group, n=4) or HVHF group (n=8) immediately after enrollment, in a 1:2 ratio. The SMT group were given standard treatment for SAP, while the HVHF group were given standard as well as 72-hour HVHF treatment initiated within 2 hours after enrollment. Patients in the 2 groups were comparable for the baseline clinical parameters. All patients were monitored over a 72-hour observation period for continuous clinical status, blood cell counts including monocytes, CD4+ and CD8+ T cells, and HLA-DR expression on monocytes. Blood samples were collected from those patients at 0, 6, 12, 24, 48, and 72 hour after enrollment for measurement of plasma Th1-type cytokines (interleukin-1 [IL-1], IL-2, interferon-gamma [IFN-gamma], and tumor necrosis factor-alpha [TNF-alpha]) and Th2-type cytokines (IL-4, IL-5, IL-6, IL-IO, and IL-13) using ELISA.
Results: Within 72 hours, all measured cytokines except IL-4 were maintained at high levels, accompanied with a low level of peripheral monocytes, CD4+ and CD8+ T cell counts, and HLA-DR expression. Seventy-two hours later, plasma cytokines IFN-gamma, IL-1, IL-2, IL-5, IL-10, and IL-13 (p<0.05), but not TNF-alpha and IL-6, in patients in the HVHF group were significantly reduced, while there was no change for these parameters in the SMT group. Plasma levels of IFN-gamma, TNF-alpha, IL-1, IL-2, IL-5, and IL-13 in the HVHF group were significantly lower than those in the SMT group. Peripheral CD4+ and CD8+ T cells, monocyte count, and HLA-DR expression were increased significantly (p<0.05) only in the HVHF group, not in the SMT group. HLA-DR expression in the HVHF group was significant higher than that in the SMT group (p<0.05).
Conclusions: HVHF significantly reduced plasma inflammatory cytokine concentrations including those of IFN-gamma, TNF-alpha, IL-1, IL-2, IL-5, and IL-13, while it increased monocyte HLA-DR expression in patients with SAP. The association of plasma cytokine reduction and cellular immune function recovery and clinical outcome needs further investigation.