title: Clinical significance of intra-amniotic inflammation in patients with preterm premature rupture of membranes.
abstract: OBJECTIVE
  This study was conducted to determine the frequency and clinical significance of intra-amniotic inflammation in patients with preterm premature rupture of the membranes.
  
  
  METHODS
  Amniotic fluid was retrieved from 219 patients with preterm premature rupture of the membranes; the fluid was cultured for aerobic and anaerobic bacteria and mycoplasmas and assayed for neutrophil collagenase, which is also known as matrix metalloproteinase-8. Matrix metalloproteinase-8 was used because previous studies indicated that this was a sensitive and specific index of inflammation and that is correlated with the amniotic fluid white blood cell count. Intra-amniotic inflammation was defined as an elevated amniotic fluid matrix metalloproteinase-8 concentration (>23 ng/mL). Nonparametric and survival techniques were used for statistical analysis.
  
  
  RESULTS
  The overall rate of intra-amniotic inflammation was 42% (93/219 samples); proven intra-amniotic infection was detected only in 23% (50/219 samples). Intra-amniotic inflammation with a negative amniotic fluid culture for micro-organisms was found in 23% (51/219 samples) and was as common as proven intra-amniotic infection. Pregnancy outcome was worse in patients with intra-amniotic inflammation and a negative culture than in those patients with a negative culture and without inflammation. There were no differences in the interval-to-delivery or rate of complications between patients with intra-amniotic inflammation and a negative culture and patients with proven amniotic fluid infection.
  
  
  CONCLUSIONS
  We conclude that intra-amniotic inflammation, regardless of culture result, is present in 42% of patients with preterm premature rupture of the membranes and that it is a risk factor for impending preterm delivery and adverse outcome. We propose that intra-amniotic inflammation, rather than infection, be used to classify and treat patients with preterm premature rupture of the membranes.
authors.affiliation: Department of Obstetrics and Gynecology, Laboratory of Fetal Medicine Research, College of Medicine, Seoul National University Seoul 110-744, Korea.
authors.forename: Soon-Sup
authors.initials: SS
authors.lastname: Shim
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Joon-Seok
authors.initials: JS
authors.lastname: Hong
authors.forename: Chan-Wook
authors.initials: CW
authors.lastname: Park
authors.forename: Jong Kwan
authors.initials: JK
authors.lastname: Jun
authors.forename: Beyong Il
authors.initials: BI
authors.lastname: Kim
authors.forename: Bo Hyun
authors.initials: BH
authors.lastname: Yoon
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000382:microbiology; D002821:Chorioamnionitis / Q000453:epidemiology; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000453:epidemiology*; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology; D020784:Matrix Metalloproteinase 8 / Q000032:analysis; D007752:Obstetric Labor, Premature / Q000453:epidemiology; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D012307:Risk Factors
chemical_list: D020784:Matrix Metalloproteinase 8