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Diversity of microbes in amniotic fluid
1Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305-5107, USA. digiulio@stanford.edu
Seminars in Fetal & Neonatal Medicine
|December 6, 2011
Summary
Polymerase chain reaction (PCR) reveals higher microbial invasion of the amniotic cavity (MIAC) rates than traditional methods. This advanced detection identifies diverse, often uncultivated, microbes linked to preterm birth, necessitating further research for improved diagnostics and treatments.
Area of Science:
- Microbiology
- Obstetrics
- Molecular Biology
Background:
- Microbial invasion of the amniotic cavity (MIAC) is a significant factor in preterm birth.
- Cultivation-based methods underestimate MIAC prevalence compared to PCR-based techniques.
- Specific microbial species have been historically associated with MIAC.
Purpose of the Study:
- To highlight the increased detection of MIAC using PCR-based 16S ribosomal DNA studies.
- To identify commonly invading and previously uncultivated microbes in the amniotic cavity.
- To explore the association between detected microbes and preterm birth, and the potential for polymicrobial synergy.
Main Methods:
- Utilizing PCR-based 16S ribosomal DNA analysis of amniotic fluid samples.
- Comparing PCR findings with traditional cultivation-based methods.
- Analyzing associations between specific microbial taxa and host factors or preterm birth outcomes.
Main Results:
- PCR detects 30-50% more MIAC cases than cultivation.
- Common invaders include Ureaplasma, Mycoplasma, Fusobacterium, Streptococcus, Bacteroides, and Prevotella spp.
- Cultivation-resistant anaerobes (e.g., Sneathia sanguinegens, Leptotrichia spp.) and uncultivated species are frequently identified.
- MIAC is polymicrobial in 24-67% of cases, with potential pathogen synergy.
- Associations support a causal link between diverse microbes and preterm birth.
Conclusions:
- PCR significantly enhances the detection of MIAC, revealing a broader microbial landscape.
- The amniotic cavity harbors a diverse and incompletely characterized microbiome.
- Further research is crucial for understanding MIAC's role in preterm birth and developing better clinical strategies.
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