Abstract
Fusobacterium nucleatum is an oral pathogen associated with preterm birth. Presented is a case of acute chorioamnionitis that progressed to maternal sepsis in a term patient with intact membranes. In addition to its role in periodontal disease and preterm birth, our case demonstrates that intrauterine infection with Fusobacterium nucleatum can result in severe disease at term.
Keywords: Fusobacterium nucleatum, Chorioamnionitis, Periodontal disease, Sepsis
Introduction
Chorioamnionitis at term is a relatively rare occurrence in the presence of intact fetal membranes. Periodontal disease is a relatively common condition in women of reproductive age and has been associated with adverse pregnancy outcomes including preterm birth, fetal demise, and premature rupture of membranes. Fusobacterium nucleatum is a common oral pathogen linked to periodontal disease and has been implicated as a causal factor in preterm birth.1,2 We present a case of severe, acute chorioamnionitis caused by Fusobacterium nucleatum in a term gestation with intact fetal membranes.
Case Presentation
A 21-year-old primigravida woman at 38 weeks gestation presented to labor and delivery triage unit with complaints of fever, abdominal cramping, and low back pain. Her prenatal course had been unremarkable. Physical examination was significant for maternal tachycardia and an axillary temperature of 38 degrees Celsius. Her physical examination was unremarkable and there was no fundal tenderness. Cardiotocogram revealed fetal tachycardia of 170 beats per minute and occasional uterine contractions. A complete blood count revealed a leukocytosis of 19,500 with a left shift. Premature rupture of membranes was ruled out with a speculum examination, and an amniotic fluid index was 19.1 centimeters. An amniocentesis revealed a white blood cell count of 1090, glucose less than 3 mg/dL, gram stain 3+ white blood cells, and no organisms were visualized on gram stain. Induction of labor with Pitocin and intravenous antibiotics were ordered. The maternal condition then abruptly deteriorated to septic shock. An emergent cesarean delivery was performed under general anesthesia for fetal bradycardia after attempts at maternal and intrauterine fetal resuscitation failed. At delivery, the amniotic fluid was malodorous and hemabate was required for uterine atony. APGAR scores were 2, 4, 5, and 7 at 1, 5, 10, and 15 minutes, respectively. The umbilical artery pH was 7.08 with a base deficit of 12.0. Postoperatively, the maternal condition improved with broad spectrum antibiotics, and extubation was successful on the first postoperative day. Maternal blood cultures were negative. Amniotic fluid cultures grew 3+ Fusobacterium nucleatum after 5 days. The diagnosis of severe acute chorioamnionitis with 3 vessel funisitis was confirmed histologically. The placenta was at the ninetieth percentile for gestational age (645g). Her postpartum course was largely unremarkable except for a right-sided mastitis 12 days postpartum that was treated with dicloxacillin. The infant was discharged after a ten-day course of intravenous antibiotics, and a two-week follow-up visit revealed a healthy and neurologically intact infant.
Discussion
Fusobacterium nucleatum is a gram negative, filamentous, and anaerobic bacterium that is part of the oral flora of many adults and is implicated in the pathogenesis of periodontal disease.1 Culture-independent techniques with 16S rRNA sequencing have been utilized to detect this difficult to cultivate organism in the amniotic fluid of women with pregnancies complicated by preterm birth.2 In fact, it is one of the most commonly isolated organisms in the amniotic fluid of women who present with preterm labor with intact membranes. In addition to its role in preterm birth, Fusobacterium nucleatum is also implicated in spontaneous premature rupture of membranes at term, and Han et al. reported a case of term stillbirth associated with Fusobacterium nucleatum chorioamnionitis in a patient with pregnancy-associated gingivitis.3,4 We present a unique case of acute chorioamnionitis at term with intact membranes.
The mode of transmission of Fusobacterium nucleatum to the intrauterine cavity in our patient is unknown. Potential routes of transmission include hematogenous spread from the oral cavity and ascending infection from the vagina. In a murine model, Han et al, demonstrated that Fusobacterium nucleatum is capable of invading the placenta via a hematogenous route and result in premature and term stillbirth.5 Ascending infection from the vagina is less likely based on previous studies showing that vaginal subspecies of Fusobacterium nucleatum are rarely isolated from amniotic fluid.6 Orogenital transmission has been implicated in a case report of a patient with clinical chorioamnionitis resulting in a preterm birth following receptive oral intercourse with a partner with significant periodontal disease.7
Our case demonstrates that the significance of intrauterine infection with Fusobacterium nucleatum is not limited to preterm birth resulting from subclinical infection, but extends beyond to include acute chorioamnionitis at term with potential adverse maternal and neonatal outcome. While most studies to date have investigated the role of periodontal disease in preterm birth, additional studies may be warranted to evaluate the relationship between chorioamnionitis at term and periodontal disease. As Fusobacterium has a known role in both periodontal disease and several adverse pregnancy outcomes, it seems prudent to recommend good oral hygiene for both the gravida and her partner.
Conflict of Interest
None of the authors identify any conflict of interest.
References
- 1.Signat B, Roques C, Poulet P, Duffaut D. Fusobacterium nucleatum in Periodontal Health and Disease. Curr Issues Mol Biol. 2011;13:25–36. [PubMed] [Google Scholar]
- 2.Han YW, Shen T, Chung P, Buhimschi IA, Buhimschi CS. Uncultivated bacteria as etiologic agents of intra-amniotic inflammation leading to preterm birth. J Clin Microbiol. 2009;47:38–47. doi: 10.1128/JCM.01206-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Han YW, Fardini Y, Chen C, Lacampo KG, et al. Term Stillbirth caused by oral Fusobacterium nucleatum. Obstet Gynecol. 2010;115:442–445. doi: 10.1097/AOG.0b013e3181cb9955. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Romero R, Gonzalez R, Sepulveda, et al. Infection and labor. VIII. Microbial invasion of the amniotic cavity in patients with suspected cervical impotence: prevalence and clinical significance. Am J Obstet Gynecol. 1992;167:1086–1091. doi: 10.1016/s0002-9378(12)80043-3. [DOI] [PubMed] [Google Scholar]
- 5.Han YW, Redline RW, Li M, Yin L, Hill GB, McCormick TS. Fusobacterium nucleatum induces premature and term stillbirths in pregnant mice: implication of oral bacteria in preterm birth. Infect Immun. 2004;72:2272–2279. doi: 10.1128/IAI.72.4.2272-2279.2004. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Hill GB. Investigating the source of amniotic fluid isolates of fusobacteria. Clin Infect Dis. 1993;16(Suppl 4):S423–S424. doi: 10.1093/clinids/16.supplement_4.s423. [DOI] [PubMed] [Google Scholar]
- 7.Dixon NG, Ebright D, Defrancesco MA, Hawkins RE. Orogenital contact: a cause of chorioamnionitis? Obstet Gynecol. 1994;84:654–655. [PubMed] [Google Scholar]