Detection of a microbial biofilm in intraamniotic infection.
OBJECTIVE
Microbial biofilms are communities of sessile microorganisms formed by cells that are attached irreversibly to a substratum or interface or to each other and embedded in a hydrated matrix of extracellular polymeric substances. Microbial biofilms have been implicated in >80% of human infections such as periodontitis, urethritis, endocarditis, and device-associated infections. Thus far, intraamniotic infection has been attributed to planktonic (free-floating) bacteria. A case is presented in which "amniotic fluid sludge" was found to contain microbial biofilms. This represents the first report of a microbial biofilm in the amniotic cavity.


METHODS
"Amniotic fluid sludge" was detected by transvaginal sonography and retrieved by transvaginal amniotomy. Bacteria were identified with scanning electron microscopy and fluorescence in situ hybridization for conserved regions of the microbial genome; the exopolymeric matrix was identified by histochemistry by the wheat germ agglutinin lectin method. The structure of the biofilm was imaged with confocal laser scanning microscopy.


RESULTS
"Amniotic fluid sludge" was imaged with scanning electron microscopy, which allowed the identification of bacteria embedded in an amorphous material and inflammatory cells. Bacteria were demonstrated with fluorescent in situ hybridization using a eubacteria probe. Extracellular matrix was identified with the wheat germ agglutinin lectin stain. Confocal microscopy allowed 3-dimensional visualization of the microbial biofilm.


CONCLUSIONS
Microbial biofilms have been identified in a case of intraamniotic infection with "amniotic fluid sludge."
Romero
Roberto
R
Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, MD, USA. nichdprbchiefstaff@mail.nih.gov
Schaudinn
Christoph
C
Kusanovic
Juan Pedro
JP
Gorur
Amita
A
Gotsch
Francesca
F
Webster
Paul
P
Nhan-Chang
Chia-Ling
CL
Erez
Offer
O
Kim
Chong Jai
CJ
Espinoza
Jimmy
J
Gonçalves
Luis F
LF
Vaisbuch
Edi
E
Mazaki-Tovi
Shali
S
Hassan
Sonia S
SS
Costerton
J William
JW
D000649:Amniocentesis; D000653:Amniotic Fluid / Q000382:microbiology; D001231:Aspergillus flavus / Q000502:physiology*; D018441:Biofilms; D002821:Chorioamnionitis / Q000175:diagnosis / Q000382:microbiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008855:Microscopy, Electron, Scanning; D019535:Mycoplasma hominis / Q000502:physiology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000000981:diagnostic imaging* / Q000382:microbiology; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013295:Streptococcus mutans / Q000502:physiology*; D016216:Ultrasonography, Prenatal