Microinflammation is involved in the dysfunction of arteriovenous fistula in patients with maintenance hemodialysis

Background Vascular access(VA) dysfunction is a major clinical complication in the hemodialysis population and has a direct effect on dialysis outcome.This study was conducted to explore the role of microinflammation in the VA dysfunction in maintenance hemodialysis patients. Methods Forty-seven patients(male 35 and female 12) receiving maintenance hemodialysis were included for this study.They were divided into three groups:group 1(n=15),patients with initial hemodialysis and new arteriovenous fistula(AVF);group 2(n=18),patients treated with hemodialysis for long term with well-functional VA;group 3(n=14), maintenance hemodialysis patients with VA dysfunction.Biochemical parameters and serum tumor necrosis factor-α(TNF-α),interleukin 6(IL-6) and monocyte chemoattractant protein-1(MCP-1) were determined.High-sensitivity C-reactive protein(hs-CRP) was determined by latex-enhanced immuno-nephelometric method.Tissues of radial artery were taken from group 1 and group 3 for the histological study.Expression of CD68 and MCP-1 in the radial artery was determined by immunohistochemistry. Results Serum hs-CRP in group 3 was significantly higher than those in group 1 and group 2((7.40±2.42) mg/L vs (4.21±1.62) mg/L and(5.04±3.65) mg/L,P <0.01 and P <0.05,respectively).Serum TNF-αin group 3 was significantly higher than those in group 1 and group 2((64.03±9.29) pg/ml vs(54.69±12.39) pg/ml and(54.05±-7.68) pg/ml,P <0.05 and P <0.01,respectively).Serum IL-6 in group 3 was also significantly higher than those in group 1 and group 2 ((70.09±14.53) pg/ml vs(56.43±10.11) pg/ml and(60.77±9.70) pg/ml,P <0.01 and P <0.05,respectively).Patients in group 3 had a thicker internal layer of vessels than in group 1((0.356±0.056) mm vs(0.111±0.021) mm,P <0.01). Expression of CD68 and MCP-1 in the fistula vessel walls in group 3 were much higher than those in group 1(P <0.01). Moreover,serum hs-CRP level was positively correlated with the neointimal hyperplasia,the expression of CD68 and MCP-1 in fistula vessel(P <0.01,respectively). Conclusion Microinflammaton might be involved in the dysfunction of AVF in patients with maintenance hemodialysis.