Interleukin-18 levels reflect the severity of acute pancreatitis

Background and goal of study

IL-18 is mainly produced by macrophages, especially by the Kupffer cells of the liver. When anti-IL-18 antibodies were administered before challenge with LPS 1 week after the injection of P. acnes, the development of liver tissue necrosis and the associated increase in serum GOT and GPT levels were prevented. We therefore studied the correlation between the serum IL-18 levels, severity of the disease, and the development of liver dysfunction in cases of acute pancreatitis.

Materials and methods

Seventeen patients with acute pancreatitis treated at our center from the early stage of the disease, were enrolled in this study. The disease state was mild in four patients, moderate in five, and severe in eight patients. The IL-18 and TNF-α levels in the serum were determined by ELISA. The correlations between the maximum serum IL-18 level and the corresponding serum TNF-α, IL-6, and IL-8 levels were studied.

Results

The levels of IL-18 were 4.3 ± 5.3 pg/ml in the mild group, 18.7 ± 67.1 pg/ml in the moderate group, and 269.6 ± 2482.1 pg/ml in the severe group. The IL-18 levels increased significantly corresponding to the severity of the disease. The group in which the complication of MODS developed showed significantly higher IL-18 levels than that in which this complication did not develop. The IL-18 levels in the survivor group were 132.0 ± 130.7 pg/ml, and those in the nonsurvivor group were 3028.6 ± 2480.8 pg/ml, the levels being significantly higher in the nonsurvivor group. Significant correlations were observed between the total bilirubin and IL-18 levels (r = 0.617, P = 0.0003).

Conclusion

In this study, the severity of acute pancreatitis was significantly correlated with the serum IL-18 levels; conversely, increased serum IL-18 levels reflected the severity of the disease. Since significant correlations between the serum IL-18 levels and APACHE II scores were also observed in cases of sepsis, such a correlation may not be specific to only acute pancreatitis.