TUMOR-NECROSIS-FACTOR-ALPHA IS ELEVATED IN PLASMA AND AMNIOTIC-FLUID OF PATIENTS WITH SEVERE PREECLAMPSIA

OBJECTIVE: Our purpose was to investigate whether markers for activati on of the immune system are present in patients with preeclampsia by a ssessing maternal plasma and amniotic fluid for tumor necrosis factor- alpha and interleukin-1 beta. STUDY DESIGN: Twenty-one patients with s evere preeclampsia composed the study group (group A). An antepartum c omparison group was composed of healthy nulliparous patients not in la bor and matched for gestational age (group B). Another control group c onsisted of term nulliparous patients in labor with uneventful pregnan cies (group C). Maternal plasma samples were collected from all patien ts at recruitment and from patients in groups A and C immediately afte r delivery and again 20 to 24 hours post partum. Amniotic fluid was al so collected from patients in groups A and C during labor. All samples were collectively assayed for tumor necrosis factor-alpha and interle ukin-1 beta by specific enzyme-linked immunoassays. RESULTS: Before la bor tumor necrosis factor-alpha was detected more frequently in the pl asma of preeclamptic patients than in the plasma of patients in group B (12/16 vs 5/16, p < 0.05) and in higher concentrations (median 35 pg /ml vs median 0 pg/ml, p < 0.05). Although tumor necrosis factor-alpha was frequently detected in the plasma of patients in group C in early labor (16/20), concentrations were higher in the four preeclamptic pa tients first sampled in early labor (210 pg/ml vs 65 pg/ml, p < 0.05). Similarly, amniotic fluid levels of tumor necrosis factor-alpha were increased in preeclamptic patients compared with control patients. At delivery tumor necrosis factor-alpha was more likely to be identified in the plasma of preeclamptic patients and was found in higher concent rations, but by 20 to 24 hours post partum measurements in the preecla mptic and control patients were similar. There were no differences in the frequency with which interleukin-1 beta was detected or the concen tration of interleukin-1 beta in any of the samples. CONCLUSIONS: Tumo r necrosis factor-alpha is increased in the plasma and amniotic fluid of patients with severe preeclampsia. These data are suggestive of a r ole for abnormal immune activation in the pathophysiologic mechanisms of preeclampsia.