title: Cervical fluid interleukin 6 and intra-amniotic complications of preterm prelabor rupture of membranes.
abstract: OBJECTIVE
  To determine if cervical fluid interleukin (IL)-6 concentrations in women with preterm prelabor rupture of membranes (PPROM) allows identification of microbial invasion of the amniotic cavity (MIAC) and/or intra-amniotic inflammation (IAI).
  
  
  METHODS
  One hundred forty-four women with singleton pregnancies complicated by PPROM were included in this prospective cohort study. Cervical and amniotic fluids were collected at the time of admission and concentrations of IL-6 were measured using an ELISA and point-of-care test, respectively. Cervical fluid was obtained using a Dacron polyester swab and amniotic fluid was obtained by transabdominal amniocentesis. MIAC was diagnosed based on a positive PCR result for Ureaplasma species, M. hominis, and/or C. trachomatis and/or by positivity for the 16 S rRNA gene. IAI was defined as amniotic fluid point-of-care IL-6 concentrations ≥745 pg/mL. The women were assigned to four subgroups based on the presence of MIAC and/or IAI: microbial-associated IAI (both MIAC and IAI), sterile IAI (IAI alone), MIAC alone, and without either MIAC or IAI.
  
  
  RESULTS
  (1) Women with microbial-associated IAI had higher cervical fluid IL-6 concentrations (median 560 pg/mL) than did women with sterile IAI (median 303 pg/mL; p = .001), women with MIAC alone (median 135 pg/mL; p = .0004), and women without MIAC and IAI (median 180 pg/mL; p = .0001). (2) No differences were found in cervical fluid IL-6 concentrations among women with sterile IAI, with MIAC alone, and without MIAC and IAI. (3) A positive correlation was observed between cervical fluid IL-6 concentrations and the amount of Ureaplasma species in amniotic fluid (copies DNA/mL; rho = 0.57, p < .0001). (4) A weak positive correlation was detected between cervical and amniotic fluid IL-6 concentrations (rho = 0.33, p < .0001).
  
  
  CONCLUSIONS
  The presence of microbial-associated IAI is associated with the highest cervical fluid IL-6 concentrations. Cervical IL-6 can be helpful in the identification of microbial-associated IAI.
authors.affiliation: a Department of Obstetrics and Gynecology , Charles University in Prague, Faculty of Medicine Hradec Kralove, University Hospital Hradec Kralove , Hradec Kralove , Czech Republic.
authors.forename: Ivana
authors.initials: I
authors.lastname: Musilova
authors.affiliation: b Department of Clinical Immunology and Allergy , Charles University in Prague, Faculty of Medicine Hradec Kralove, University Hospital Hradec Kralove , Hradec Kralove , Czech Republic.
authors.forename: Ctirad
authors.initials: C
authors.lastname: Andrys
authors.affiliation: b Department of Clinical Immunology and Allergy , Charles University in Prague, Faculty of Medicine Hradec Kralove, University Hospital Hradec Kralove , Hradec Kralove , Czech Republic.
authors.forename: Marcela
authors.initials: M
authors.lastname: Drahosova
authors.affiliation: b Department of Clinical Immunology and Allergy , Charles University in Prague, Faculty of Medicine Hradec Kralove, University Hospital Hradec Kralove , Hradec Kralove , Czech Republic.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Soucek
authors.affiliation: c Institute of Clinical Biochemistry and Diagnostics, University Hospital Hradec Kralove , Hradec Kralove , Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Pliskova
authors.affiliation: d Department of Obstetrics and Gynecology , Sahlgrenska Academy, Gothenburg University , Gothenburg , Sweden.|e Domain of Health Data and Digitalization , Norwegian Institute of Public Health , Oslo , Norway.
authors.forename: Bo
authors.initials: B
authors.lastname: Jacobsson
authors.affiliation: a Department of Obstetrics and Gynecology , Charles University in Prague, Faculty of Medicine Hradec Kralove, University Hospital Hradec Kralove , Hradec Kralove , Czech Republic.|f Biomedical Research Center, University Hospital Hradec Kralove , Hradec Kralove , Czech Republic.
authors.forename: Marian
authors.initials: M
authors.lastname: Kacerovsky
mesh_terms: D000328:Adult; D000649:Amniocentesis; D000650:Amnion / Q000382:microbiology*; D000653:Amniotic Fluid / Q000737:chemistry* / Q000382:microbiology; D015415:Biomarkers / Q000032:analysis; D002821:Chorioamnionitis / Q000175:diagnosis / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000209:etiology / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D015850:Interleukin-6 / Q000032:analysis*; D000067716:Point-of-Care Testing; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011446:Prospective Studies; D014509:Ureaplasma / Q000302:isolation & purification; D016869:Ureaplasma Infections / Q000175:diagnosis / Q000382:microbiology; D055815:Young Adult
chemical_list: D015415:Biomarkers; D015850:Interleukin-6
keywords: Microbial invasion of the amniotic cavity; cytokine; intra-amniotic inflammation; noninvasive sample; preterm delivery