Serum Pro-Inflammatory Cytokines; IL-6 and TNF-α Profiles and their Correlation with Severity of Pre-Eclampsia in Benin City, Nigeria

Abstract

Background: A generalised inflammatory response intricately involving placenta formation and immune maladaptation is considered the main pathology in pre-eclampsia. Pro-inflammatory cytokines: Interleukin-6 and Tumour necrosis factor-alpha, amongst several other factors, have been implicated in the aetio-pathophysiology with their levels correlating to the severity of pre-eclampsia.
This study was undertaken to describe the pattern of expression of IL-6 and TNF-α, and their significance in determining the severity of pre-eclampsia in Nigerian pregnant women. Method: This was a prospective case-control study among 96 pregnant women; 48 with pre-eclampsia and matched 48 without pre-eclampsia at the University of Benin Teaching Hospital, Benin City, Nigeria. Venous blood serum levels of IL-6 and TNF-α were determined using enzyme-linked immunosorbent assay procedures. Relevant socio-demographic, clinical variables and serum levels of IL-6 and TNF-α levels were obtained and analysed using SPSS 17. The P value was set at <0.05. Results: Proteinuria was statistically different (p = < 0.001) between cases and controls. The mean serum concentrations of IL-6 and TNF-α for cases were 36.21 ± 60.18 pg/ml and 3.26 ± 2.14 pg/ml as against 8.24 ± 15.26 pg/ml and 3.45 ± 3.14 pg/ml for controls respectively. The P values were <0.001 and 0.167 respectively. The mean serum concentrations of IL-6 and TNF-α for mild pre-eclampsia were 13.89 ± 23.27 pg/ml and 3.29 ± 2.82 pg/ml as against 56.74 ± 75.36 pg/ml and 3.23 ± 1.31 pg/ml for severe pre-eclampsia respectively. The P-values were <0.001 and 0.160 respectively. The serum concentrations of IL-6 positively correlated with the severity of pre-eclampsia. Conclusion: Serum concentration of IL-6 depicts and positively correlates with the severity of pre-eclampsia in our environment. TNF-α, though also associated with pre-eclampsia, its serum concentration is not positively correlated with the severity of the disease in this study