Interleukin-18 in the plasma of women with preeclampsia

Objective: Interleukin-18 (IL-18) is a proinflammatory cytokine capable of stimulating interferon gamma and tumor necrosis factor-α production. Our purpose was to determine whether abnormal levels of IL-18 in maternal plasma correlate with the diagnosis of preeclampsia. Study Design: A case control study design was used to enroll 61 patients: controls (n = 31) and preeclamptic women (n = 30). A standard enzyme-linked immunosorbent assay measured plasma IL-18. Statistical methods included Student t tests and χ2 tests. Results: Mean IL-18 levels were lower in preeclampsia than in controls (185 ± 74 pg/mL vs 224 ± 75 pg/mL, P = .053). Administration of betamethasone (BMZ) and/or hydralazine (HYD) was significantly associated with a lower IL-18 compared with controls (159 ± 50 pg/mL vs 224 ± 75 pg/mL, P = .002). After women who received BMZ or HYD were excluded, levels of IL-18 in preeclampsia were similar to those of controls (213 ± 87 pg/mL, P = .69). There was no association between gestational age and IL-18. Conclusion: Lower IL-18 was associated with administration of either BMZ or HYD. After patients receiving these medications were excluded, IL-18 levels were similar in controls and preeclamptic women. IL-18 was not associated with gestational age. (Am J Obstet Gynecol 2003;188:1234-7.)