title: Characterization of chorioamnionitis in 2nd-trimester C-section placentas and correlation with microorganism recovery from subamniotic tissues.
abstract: Prolonged exposure to infection appears to influence fetal/neonatal development. We characterize the relationship between histologic patterns of inflammation and microorganism recovery from the placentas of live born infants delivered before the 28th postmenstrual week. The subamniotic parenchyma of 835 placentas delivered by cesarean section were cultured and evaluated for specific histologic patterns of inflammation in a blinded fashion. Cases with prolonged membrane rupture were excluded. Microorganisms were recovered from 41% of placentas. Microorganisms found more frequently in placentas with high-grade chorionic plate inflammation include Actinomyces, Prevotella bivia, Corynebacterium sp., Escherichia coli, Peptostreptococcus magnus, multiple species of Streptococci, and Mycoplasma sp., including Ureaplasma urealyticum. These microorganisms were also associated with fetal vasculitis (neutrophilic infiltration of chorionic plate stem vessels or umbilical cord). Recovery of microorganisms from placental parenchyma is associated with histologic inflammation. The same microorganisms responsible for inciting high-grade chorionic plate inflammation are also most likely to promote fetal inflammation.
authors.affiliation: Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA. JLHecht@bidmc.harvard.edu
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Hecht
authors.forename: Andrew
authors.initials: A
authors.lastname: Onderdonk
authors.forename: Mary
authors.initials: M
authors.lastname: Delaney
authors.forename: Elizabeth N
authors.initials: EN
authors.lastname: Allred
authors.forename: Harvey J
authors.initials: HJ
authors.lastname: Kliman
authors.forename: Eduardo
authors.initials: E
authors.lastname: Zambrano
authors.forename: Solveig M
authors.initials: SM
authors.lastname: Pflueger
authors.forename: Chad A
authors.initials: CA
authors.lastname: Livasy
authors.forename: Ina
authors.initials: I
authors.lastname: Bhan
authors.forename: Alan
authors.initials: A
authors.lastname: Leviton
mesh_terms: D001419:Bacteria / Q000145:classification / Q000302:isolation & purification*; D002585:Cesarean Section; D002821:Chorioamnionitis / Q000382:microbiology* / Q000473:pathology*; D002823:Chorion / Q000098:blood supply / Q000382:microbiology; D005260:Female; D005865:Gestational Age; D006801:Humans; D007249:Inflammation / Q000473:pathology; D007752:Obstetric Labor, Premature; D010920:Placenta / Q000382:microbiology* / Q000473:pathology*; D010922:Placenta Diseases / Q000382:microbiology* / Q000473:pathology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000382:microbiology* / Q000473:pathology*; D011262:Pregnancy Trimester, Second; D047928:Premature Birth; D014470:Umbilical Cord / Q000382:microbiology; D014481:United States; D014657:Vasculitis / Q000382:microbiology