Cytokines in the peritoneal fluid of patients with endometriosis

OBJECTIVE: To determine which of the various cytokines interleukin-5 (IL-5), interleukin-6 (IL-6) and interleukin-1 (IL-1) are important in endometriosis. METHODS: Peritoneal fluid (PF) samples were taken from 55 women at the time of either laparotomy or laparoscopy, and were examined for the levels of IL-5, IL-6 and IL-1 using each cytokine specific sandwich enzyme-linked immunosorbent assay. Thirty-two patients had pelvic endometriosis, eight post-pelvic inflammatory disease, four advanced cancer, three adenomyosis, three benign ovarian tumor, and other diseases. Statistical analysis was performed with the Mann Whitney test, chi-square test or Fisher's test. RESULTS: Both IL-5 and IL-6 levels in PF specimens with endometriosis tended to be higher than normal, while the same specimens were mostly interleukin-1 beta (IL-1 beta) negative. Of great interest was the negative correlation between log (IL-5) and IL-6 (Fisher's test, P < 0.04). CONCLUSION: These findings support the concept that IL-5 and IL-6 but not IL-1 are associated with endometriosis.