The diagnostic and prognostic value of amniotic fluid white blood cell count, glucose, interleukin-6, and gram stain in patients with preterm labor and intact membranes.
OBJECTIVE
Our goal was to compare the value of amniotic fluid tests in the detection of microbial invasion of the amniotic cavity and in the relationship with the amniocentesis-to-delivery interval and neonatal complications in patients with preterm labor and intact membranes.


METHODS
Amniotic fluid was retrieved by transabdominal amniocentesis from 120 patients with preterm labor and intact membranes. Fluid was cultured for aerobic and anaerobic bacteria and for mycoplasmas. Amniotic fluid analysis included a Gram stain, white blood cell count, glucose and interleukin-6 determinations. Logistic regression and Cox's proportional hazards model were used for analysis.


RESULTS
(1) The prevalence of positive amniotic fluid cultures was 9.2% (11/120); (2) patients with microbial invasion had a shorter amniocentesis-to-delivery interval and a higher neonatal complications rate than patients with a negative culture; (3) the most sensitive test for the detection of microbial invasion of the amniotic cavity was amniotic fluid interleukin-6 determinations (cutoff 11.3 ng/ml) (sensitivity; for interleukin-6 100%, for glucose 81.8%, for white blood cell count 63.6%, and for Gram stain 63.6%; p < 0.05 for all comparisons); (4) the most specific test was the Gram stain of amniotic fluid (specificity: for Gram stain 99.1%, for white blood cell count 94.5%, for interleukin-6 82.6%, and for glucose 81.6%; p < 0.01 for all); (5) of all amniotic fluid tests, interleukin-6 determinations were the only ones that had significant relationship with the amniocentesis-to-delivery interval and neonatal complications.


CONCLUSIONS
Interleukin-6 concentrations in amniotic fluid are better indicators of microbial invasion of the amniotic cavity, amniocentesis-to-delivery interval, and neonatal complications than the amniotic fluid Gram stain, glucose concentration, or white blood cell count.
Romero
R
R
Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI 48201.
Yoon
B H
BH
Mazor
M
M
Gomez
R
R
Diamond
M P
MP
Kenney
J S
JS
Ramirez
M
M
Fidel
P L
PL
Sorokin
Y
Y
Cotton
D
D
D000328:Adult; D000649:Amniocentesis; D000653:Amniotic Fluid / Q000737:chemistry* / Q000166:cytology / Q000382:microbiology; D002821:Chorioamnionitis / Q000150:complications / Q000453:epidemiology / Q000382:microbiology; D005321:Extraembryonic Membranes / Q000166:cytology; D005260:Female; D005840:Gentian Violet; D005947:Glucose / Q000032:analysis*; D016908:Gram-Positive Bacterial Infections / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D015850:Interleukin-6 / Q000032:analysis*; D007958:Leukocyte Count; D009017:Morbidity; D007752:Obstetric Labor, Premature / Q000175:diagnosis* / Q000209:etiology; D010619:Phenazines; D011237:Predictive Value of Tests; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis* / Q000453:epidemiology; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D015995:Prevalence; D011379:Prognosis; D013194:Staining and Labeling
C035863:Gram's stain; D015850:Interleukin-6; D010619:Phenazines; D005947:Glucose; D005840:Gentian Violet