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Eradication of intra-amniotic Streptococcus mutans in a woman with a short cervix
Anne-Maude Morency1, Fabien Rallu1, Céline Laferrière1
1Department of Microbiology, Centre Hospitalier Universitaire-Hôpital Sainte-Justine, Université de Montréal, Montreal QC.
Background:
Microbial invasion of the amniotic cavity (MIAC) remains an important pathogenetic factor in preterm births. Although most MIACs seem to originate in vaginal microflora, other reservoirs such as the oral microflora have been suggested.
Case:
We report a case of successful eradication of Streptococcus mutans (a bacterium generally found in dental plaque) from the amniotic cavity, using ampicillin, gentamycin, and azythromycin in a woman who presented with threatened preterm labour and a short cervix at 25 weeks' gestation. She delivered at 34 weeks' gestation and was treated for tooth decay 12 weeks after delivery.
Conclusion:
Intra-amniotic infection should be suspected in the presence of a short cervix during the second trimester. Appropriate parenteral antibiotics can eradicate intra-amniotic infection and potentially prolong pregnancy.
Insights
Microbial invasion of the amniotic cavity (MIAC) can cause preterm birth. This case shows antibiotics can clear intra-amniotic Streptococcus mutans infection, potentially prolonging pregnancy.
Area of Science:
- Obstetrics and Gynecology
- Infectious Diseases
- Microbiology
Background:
- Microbial invasion of the amniotic cavity (MIAC) is a significant cause of preterm birth.
- While vaginal microflora is a common source, oral microflora is an emerging suspected reservoir for MIAC.
- Early identification and management of MIAC are crucial for improving pregnancy outcomes.
Observation:
- A case report details a pregnant woman at 25 weeks' gestation presenting with threatened preterm labor and a short cervix.
- The patient was diagnosed with intra-amniotic infection caused by Streptococcus mutans, a bacterium typically found in dental plaque.
- Treatment involved a course of parenteral antibiotics: ampicillin, gentamycin, and azithromycin.
Findings:
- Successful eradication of Streptococcus mutans from the amniotic cavity was achieved with the prescribed antibiotic regimen.
- The patient delivered a healthy infant at 34 weeks' gestation, indicating a prolonged pregnancy.
- The mother received dental treatment for tooth decay 12 weeks postpartum.
Implications:
- Intra-amniotic infection should be considered in cases of a short cervix during the second trimester.
- Parenteral antibiotic therapy can effectively treat intra-amniotic infections.
- Prompt treatment of MIAC may help prolong pregnancy and improve neonatal outcomes.
