Pro-inflammatory effect of C-reactive protein and interleukin-6 in pre dialysis patients and its relation to atherothrombotic profile

ABSTRACT

The present study was undertaken to determine the level of circulating C-reactive protein and interleukin-6 in the sera of predialysis chronic renal failure patients and to correlate the levels of CRP and IL-6 with renal function. This study was carried out in Internal Medicine Departments and Tanta university hospitals during the period from September 2003 to April 2005. fifty five subjects were included in this study. They were divided into two main groups. Group I [n = 15] healthy individuals [9 males and 6 females] with mean age 51.1 +/- 9.8 years as a control group ,Group II [n - 40] predialysis chronic renal failure patients [24 males and 16females] with mean age 52.3 +/- 77.5 years. 16patients [40%] were chronic glomerulonephritis, 4 patients [10%] were chronic interstitial nephritis, 3 patients [7.5%] were poly cystic kidney disease, 1 patient [2.5%] was hydronephrosis and 16 patient] 40%] were of unknown causes. They had no other predisposing factors that may elevate the serum levels C-reactive protein or Interleukin-6 e.g infection, diabetes mellitus, other systemic inflammatory diseases or auto immune diseases. This group was subdivided into two subgroups subgroup [a] included patients with creatinine clearance 25 ml/min or more [n = 18], and subgroup [b] included patients with creatinine clearance less than 25 ml/min [n = 22]. All subjects were subjected to full history taking, complete physical examination, abdominal ultrasound and the following investigations serum creatinine, creatinine clearance, urea, albumin, total serum cholesterol, triglycerides, HDL, LDL, C-reactive protein and interleukin-6. Mean CRP in control group was 2.87 +/- 1.13 mg/L, while in patients group was 10.44 +/- 7.64 mg/L with a highly significant increase in patients group than control group [P < 0.000 1]. Mean CRP in subgroup [a] was 5.08 +/- 2.25 mg/l, while in subgroup [b] was 14.83 +/- 7. 71mg/l with a highly significant increase in subgroup [b] than subgroup [a] [P < 0.0001] Mean IL-6 in control group was 2.37 +/- 1.02 pg/ml, while in patients group was7.39 +/- 4.47 pg/ml ,with a highly significant increase in the group II than the control group [P < 0.0001] Mean IL-6 in subgroup [a] was 4.60 +/- 1.92 pg/ml, while in subgroup [b] was 9.67 +/- 4.70 pg/ml with a highly significant increase in subgroup [b] than subgroup [a] [p < 0.0001]. Significant inverse correlation between creatinine clearance and CRP was found [CRP versus Cr.clr = 0.704, P < 0.0001]. Also, a negative correlation was found between Cr.clr and IL-6 [IL-6 versus Cr.clr = -0.593, P < 0.0001]. There was mild significant correlation between creatinine clearance and HDL [P = 0.001]. A significant correlation between CRP and IL-6 [r = 0.637, P < 0.0001]. Negative significant correlation was found between CRP and albumin [CRP versus albumin r = -0.57, P < 0.0001]. There was increase in CRP and IL-6 and so inflammation and tissue damage, atherosclerosis, coronary and vascular disease with slight hyperlipidemia, which confirm that inflammation have a cardinal role in vascular disease, atherosclerosis and tissue damage in predialysis chronic renal failure patients