Serum zonulin concentrations measured using a commercial ELISA in patients with mechanical bowel obstruction: A prospective case-control study

Background: Zonulin is a physiological regulator of intestinal permeability, but its relationship with ileus has not been directly evaluated. This study evaluated serum zonulin concentrations measured using a commercial ELISA in patients with mechanical bowel obstruction and compared them with concentrations in healthy controls. Methods: The study was designed as a prospective observational study. A total of 117 individuals were included, including 58 patients with ileus and a control group of 59 healthy individuals. Serum zonulin concentrations were measured using a commercial ELISA and compared between the groups. Results: Median serum zonulin concentrations were 10.28 ng/mL (0.63:39.17) in the patient group and 27.34 ng/mL (2.23:68.48) in the control group (p<0.001). After adjustment for age and gender using multivariable median regression, mechanical bowel obstruction remained associated with lower serum zonulin concentrations (adjusted b=-18.81 ng/mL, 95% CI: -23.57 to -14.05; p<0.001). Conclusion: Serum concentrations measured using a commercial zonulin ELISA were lower in patients with mechanical bowel obstruction than in healthy controls. Further studies using appropriately matched symptomatic controls, serial measurements, and validated intestinal injury markers are needed to determine the clinical significance of this finding.