title: Predictive value of intra-amniotic and serum markers for inflammatory lesions of preterm placenta.
abstract: OBJECTIVE
  To compare the relative predictive values of amniotic fluid (AF) matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), and serum C-reactive protein (CRP) for histologic chorioamnionitis and intra-amniotic infection in women with preterm labor or preterm premature rupture of membranes (PROM).
  
  
  METHODS
  This retrospective cohort study included 99 consecutive women with preterm labor or preterm PROM (21-35 weeks' gestation) who delivered within 72 h of transabdominal amniocentesis. The AF was cultured for aerobic and anaerobic bacteria and for genital mycoplasmas and was assayed for MMP-9 and IL-6 levels. Maternal serum CRP was measured immediately after amniocentesis. The placentas were examined histologically.
  
  
  METHODS
  histologic chorioamnionitis and intra-amniotic infection.
  
  
  RESULTS
  The prevalence of histologic chorioamnionitis and a positive AF culture was 44% (44/99) and 28% (28/99), respectively. In predicting intra-amniotic infection, AF MMP-9 had a significantly higher area under the curve (AUC: 0.94 [95% CI, 0.87-0.98]) than AF IL-6 (0.87 [95% CI, 0.78-0.84]; P < 0.05) and serum CRP (0.76 [95% CI, 0.66-0.84]; P < 0.001) and a higher sensitivity and specificity than serum CRP (P < 0.01, respectively). However, in predicting histologic chorioamnionitis, there were no significant differences in AUCs among the three tests (AF MMP-9: 0.78 [95% CI, 0.68-0.85]; AF IL-6: 0.76 [95% CI, 0.66-0.84]; serum CRP: 0.76 [95% CI, 0.66-0.84]). In a sub-analysis of 71 women without intra-amniotic infection, histologic chorioamnionitis was associated with an elevated serum CRP level (P < 0.05), but not with the level of AF IL-6 or MMP-9 (P = 0.232 and P = 0.402, respectively).
  
  
  CONCLUSIONS
  The AF MMP-9 has a better overall diagnostic performance than the AF IL-6 and maternal serum CRP in predicting intra-amniotic infection. However, the serum CRP level obtained up to 72 h before delivery appears to be an important marker for early identification of histologic chorioamnionitis in women without intra-amniotic infection.
authors.affiliation: Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do, Republic of Korea.
authors.forename: K J
authors.initials: KJ
authors.lastname: Oh
authors.forename: K H
authors.initials: KH
authors.lastname: Park
authors.forename: S-N
authors.initials: SN
authors.lastname: Kim
authors.forename: E H
authors.initials: EH
authors.lastname: Jeong
authors.forename: S Y
authors.initials: SY
authors.lastname: Lee
authors.forename: H Y
authors.initials: HY
authors.lastname: Yoon
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000378:metabolism*; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D002097:C-Reactive Protein / Q000378:metabolism; D002821:Chorioamnionitis / Q000097:blood / Q000175:diagnosis / Q000378:metabolism*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood / Q000378:metabolism*; D015850:Interleukin-6 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D007752:Obstetric Labor, Premature / Q000097:blood / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism*; D011237:Predictive Value of Tests; D011247:Pregnancy; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D015850:Interleukin-6; D002097:C-Reactive Protein; D020780:Matrix Metalloproteinase 9