Blood Interleukin-18 (IL-18) and IL-18 Binding Protein (IL-18BP) Levels Following Midline Laparotomy: A Prospective Randomized Study of Patients With Benign Disease and Patients With Cancer.

BACKGROUND/AIM: The acute phase immune response (APR) in midline laparotomy (MLa) patients following surgery has been rarely studied, with no studies assessing the association of blood IL-18 (interleukin-18) and IL-18BP (IL-18 binding protein) values with the numeric rating scale (NRS) pain score following MLa.

PATIENTS AND METHODS: Blood levels of seven cytokines (CYT) (IL-18, IL-18BP, IL-1ra, IL-6, IL-8, IL-10, IL-1β) and high-sensitivity C-reactive protein (hs-CRP) were measured at three time points; before operation (PRE), immediately after operation (POP1), and 24 h after operation (POP2) in 56 patients with MLa. The satisfaction of the patients at 24 h following MLa (SFS24 ; 0=fully unsatisfied; 10=fully satisfied) was recorded on a 11-point numeric rating scale.

RESULTS: In all patients, the IL-18 and IL-18BP blood levels decreased at POP1 and the drop between the preoperative and POP1 levels in the IL-18 and IL-18BP was highly significant (p<0.001). However, the median IL-18 and IL-18BP blood levels increased significantly at POP2 (p<0.001) with the linear mixed-effect model (LME) showing a statistically significant time effect (p<0.001). The hs-CRP blood levels increased significantly at POP2 with the LME model showing a statistically significant time effect. The preoperative and POP2 IL-18 values were clearly higher in patients with cancer versus benign disease (177/182 vs. 135/126, p=0.039/p=0.013, respectively). Interestingly, in all patients of the study, the median IL-18 versus IL-18BP blood levels correlated at POP1 (r=0.315, p=0.036).

CONCLUSION: A noteworthy discovery of this study is the correlation of IL-18BP with SFS24 (r=0.361, p=0.05), proposing that APR and quality of life are associated in MLa patients.