Microbial invasion and cytokine response in amniotic fluid in a Swedish population of women with preterm prelabor rupture of membranes.
BACKGROUND
Previous studies have shown an association between intra-amniotic microbial invasion and/or inflammation and spontaneous preterm birth. The aim of this study was to investigate the occurrence of intra-amniotic microorganisms and cytokines [interleukin (IL)-6 and IL-8] in a Swedish population, with low incidence of preterm birth, of women with preterm prelabor rupture of membranes and their correlation to preterm birth.


METHODS
Amniotic fluid was retrieved transabdominally from 58 patients with preterm prelabor rupture of membranes before 34 weeks of gestation. Polymerase chain reaction (PCR) analyses for Ureaplasma urealyticum and Mycoplasma hominis and culture for aerobic and anaerobic bacteria were performed. IL-6 and IL-8 were analyzed with enzyme-linked immunosorbent assay (ELISA).


RESULTS
Microorganisms in amniotic fluid were detected in 13 patients (25%). Patients with bacteria detected in the amniotic fluid had significantly higher levels of IL-6 and IL-8. An amniotic fluid concentration of IL-6 >/= 0.80 ng/ml [relative risk 1.93, 95% confidence interval (CI) 1.13-3.29, sensitivity 63%, specificity 75%] was associated with an increased risk of delivery within 7 days. There was also an association between IL-8 and preterm birth (< 34 weeks).


CONCLUSIONS
Intra-amniotic microbial invasion and inflammation in this population of Swedish women with preterm prelabor rupture of membranes were similar to data reported from populations with a higher incidence of preterm delivery. Amniotic IL-6 correlated to the presence of microorganisms and delivery within 7 days and IL-8 to delivery before 34 weeks.
Jacobsson
Bo
B
Perinatal Center, Department of Obstetrics and Gynecology, Institute for the Health of Women and Children, Sahlgrenska University Hospital, Göteborg, Sweden. bo.jacobsson@obgyn.gu.se
Mattsby-Baltzer
Inger
I
Andersch
Björn
B
Bokström
Hans
H
Holst
Rose-Marie
RM
Nikolaitchouk
Natalia
N
Wennerholm
Ulla-Britt
UB
Hagberg
Henrik
H
D000328:Adult; D000649:Amniocentesis; D000653:Amniotic Fluid / Q000276:immunology* / Q000382:microbiology*; D001420:Bacteria, Aerobic / Q000302:isolation & purification; D001421:Bacteria, Anaerobic / Q000302:isolation & purification; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000276:immunology / Q000382:microbiology*; D006801:Humans; D015850:Interleukin-6 / Q000032:analysis*; D016209:Interleukin-8 / Q000032:analysis*; D016015:Logistic Models; D019535:Mycoplasma hominis / Q000302:isolation & purification; D007752:Obstetric Labor, Premature / Q000276:immunology / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology / Q000382:microbiology*; D011256:Pregnancy Outcome; D011446:Prospective Studies; D012307:Risk Factors; D013548:Sweden; D016990:Ureaplasma urealyticum / Q000302:isolation & purification
D015850:Interleukin-6; D016209:Interleukin-8