Peritoneal fluid concentrations of interleukin-8 in women with endometriosis: relationship to stage of disease

There is increasing evidence that immunological mechanisms play a role inthe pathogenesis and pathophysiology of endometriosis. It was therefore ofinterest to study interleukin-8 (IL-8), a chemokine, in the peritonealfluid and peripheral blood of women undergoing laparoscopic procedures. Thepresence and concentrations of IL-8 in relation to endometriosis,infertility and abdominal pain were evaluated. Samples of peritoneal fluid(n = 49) and peripheral blood (n = 50) were obtained from 50 consecutivepatients undergoing laparoscopic surgery for various gynaecologicalindications (abdominal pain, infertility, sterilization). IL-8 was presentin the peritoneal fluid of most women (87%). The concentration of IL-8 inthe peritoneal fluid was higher in women with endometriosis compared towomen without (P = 0.02). This difference was more pronounced in early(stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritonealfluid were also higher in women with early endometriosis compared to womenwith later stages of the disease (P = 0.003). Peripheral bloodconcentrations did not correlate with peritoneal fluid concentrations ofIL-8 and/or the presence of endometriosis. We conclude that IL-8 is animportant factor that may contribute to the pathogenesis of endometriosispossibly by promoting neovascularization. This information can be a guidein the development of new therapeutic approaches for the treatment ofendometriosis.