Serum level of interleukin-6 (IL-6) and N-terminal propeptide of procollagen type I (PINP) in patients with liver diseases

Abstract

Introduction: The aim of this study was to evaluate the concentration of interleukin-6 and N-terminal propeptide of procollagen type I and their relationship in liver diseases of different etiologies.

Material and methods: Serum samples were obtained from 30 healthy volunteers and patients suffering from alcoholic cirrhosis (AC) – 31, non-alcoholic cirrhosis (NAC) – 28 and toxic hepatitis (HT) – 23 patients. Cirrhotic patients were classified according to Child–Pugh score. IL-6 and PINP concentrations were determined according to the electrochemiluminescence immunoassay.

Results: The mean serum IL-6 concentration was significantly higher in AC (mean ± SD:21.52 ± 15.01 pg/mL), NAC (20.07 ± 32.12 pg/mL) and HT (15.14 ± 17.18 pg/mL) when compared to the control group (C) (1.67 ± 0.42 pg/mL) (Mann–Whitney U test: p < .001 for all comparisons). The mean serum PINP concentration was significantly higher only in patients with AC (104.32 ± 54.50 ng/mL) in comparison with the control group (54.70 ± 19.83 ng/mL; p < .001). The mean values of IL-6 and PINP significantly differed between liver diseases (ANOVA rank Kruskal–Wallis test: p = .020 and p < .001, respectively). Accordingly, the serum levels of IL-6 and PINP were significantly higher in patients with AC than that in NAC (p < .001 and p = .022, respectively). IL-6 and PINP concentrations appeared to vary depending on the severity of liver damage (p < .001 for both). The concentrations of IL-6 and PINP were significantly higher in class C (31.88 ± 21.51 pg/mL; 132.73 ± 65.63 ng/mL, respectively) than that in class A (6.12 ± 9.00 pg/mL; 57.32 ± 28.85 ng/mL, respectively) (p < .001 for both). There were also significant differences in IL-6 concentrations between Child–Pugh class B (27.88 ± 24.45 pg/mL) and class A (6.12 ± 9.00 pg/mL; p < .001).

Conclusions: We conclude that serum concentrations of IL-6 and PINP change in liver diseases, and those changes reflect the severity of liver disease.

Keywords:

• Interleukin-6
• N-terminal propeptide of procollagen type I
• liver cirrhosis
• toxic hepatitis
• biomarkers

Disclosure statement

The authors declare that they have no conflict of interest.

Additional information

Funding

This research did not receive any specific grants from funding agencies in the public, commercial, or not-for-profit sectors.