Peritoneal cytokines and adhesion formation in endometriosis: an inverse association with vascular endothelial growth factor concentration

Objective To evaluate inflammatory/angiogenic cytokines—interleukin-1β (IL-1β), IL-6, IL-8, IL-12, interferon-γ (IFN-γ), tumor necrosis factor (TNF), and vascular endothelial growth factor A (VEGF-A)—in the peritoneal fluid of patients with endometriosis in relation to the occurrence and severity of pelvic adhesions and in control women without pelvic pathology. Design Case-control study. Setting University research institution and hospital. Patient(s) Sixty-five women with laparoscopically and histopathologically confirmed endometriosis, including 40 women with pelvic adhesions, and 37 control women without pelvic pathology. Intervention(s) Peritoneal fluid aspirated during routine diagnostic laparoscopic examination. Main Outcome Measure(s) Cytokines evaluated in the peritoneal fluid via specific enzyme-linked immunosorbent assays. Result(s) Endometriosis and the revised American Fertility Society score of this disease were associated with statistically significantly increased levels of peritoneal IL-6 and IL-8 whereas the incidence and score of endometriosis-related pelvic adhesions were negatively associated with increased levels of VEGF-A. Notably, the concentration of VEGF-A predicted adhesion development and severity after adjustment for endometriosis severity. The adhesion score also correlated with increased levels of IL-6; however, after adjustment for endometriosis severity, the effect of this cytokine was no longer statistically significant. Conclusion(s) Increased levels of VEGF-A may be associated with a decreased rate of pelvic adhesion formation in the course of endometriosis.