RESUMEN
OBJECTIVE: To assess the measurement of plasma tumor necrosis factor alpha (TNF-alpha) as a predictive test for the development of preeclampsia. STUDY DESIGN: One-hundred and twenty pregnant women were included in this prospective longitudinal study. Maternal plasma TNF-alpha levels were measured in the first, second and third trimesters by immunosorbent assay (ELISA). Preeclamptic patients were determined prospectively. Preeclamptic and normotensive patients were compared to assess the predictive value of TNF-alpha in preeclampsia. RESULTS: Ninety patients completed the study. Preeclampsia developed in 10 out of 90 patients (11.1%). Plasma TNF-alpha levels were higher in preeclamptic patients than normotensive women in the third trimester of pregnancy (P<0.05). No difference was found between groups in the first and second trimesters (P>0.05). With the use of the receiver operating characteristics (ROC) 10.13 pg/ml was found to be a cut-off value predictive for the development of preeclampsia in the third trimester, but cut-off values in the first and second trimesters could not be found. The specificity, sensitivity, positive and negative predictive values were 90, 78, 33 and 98%, respectively. CONCLUSION: This study shows that plasma TNF-alpha levels are not useful as a specific marker for prediction of preeclampsia in the first and second trimesters. But determination of TNF-alpha may be useful for the prediction in the early third trimester.