Journal of Perinatology (2010) 30, 688–690 r 2010 Nature America, Inc. All rights reserved. 0743-8346/10 www.nature.com/jp PERINATAL/NEONATAL CASE PRESENTATION Placental intravascular organisms: a case report

A Matoso1,3, S Shapiro2, ME De Paepe2,3 and F Gundogan2,3 1Departments of Pathology and Laboratory Medicine, Rhode Island Hospital, Providence, RI, USA; 2Women and Infants’ Hospital, Providence, RI, USA and 3Brown University Alpert Medical School, Providence, RI, USA

A maternal response to ascending bacterial infection often Ascending amniotic fluid bacterial infection is a cause of perinatal results in neutrophilic infiltration of the placental membranes and morbidity and mortality. A diagnosis of amniotic cavity infection can be chorionic plate (chorioamnionitis). Conversely, acute vasculitis of inferred by documenting maternal (acute chorioamnionitis) and/or fetal umbilical cord and/or chorionic vessels corresponds to the fetal (chorionic plate vasculitis; umbilical vasculitis/funisitis) inflammatory inflammatory response.2 The inflammatory response varies by the response. A definitive diagnosis of intrauterine/neonatal sepsis as a cause of offending agent/microorganism and the host immune response stillbirth requires positive blood cultures obtained at postmortem and does not always correlate with the clinical outcome. Although examination. However, if postmortem examination is not performed, acute amniotic fluid infection has been linked to stillbirth, in the absence chorioamnionitis with/without fetal inflammatory response cannot be of postmortem evidence such as positive blood cultures, it is classified as a cause of demise. We present a case of intrauterine demise difficult to classify it as the precise cause of demise. Herein, we associated with acute chorioamnionitis, villitis, and intervillositis of the present a case of intrauterine fetal demise of diamniotic- placenta. Although postmortem examination was denied, a conclusive monochorionic twins with acute chorioamnionitis, villitis, and diagnosis of intrauterine sepsis could be rendered by demonstration of intervillositis in which gram-positive cocci were found within gram-positive cocci within fetal vessels of umbilical cord, chorionic plate, umbilical cord, chorionic, and stem villous vessels. This case and stem villi. This report highlights the importance of identification of invites consideration of placental intravascular organisms as a placental intravascular organisms as unequivocal evidence of fetal sepsis, marker of intrauterine sepsis and a cause of demise. especially in cases where cultures cannot be obtained. Journal of Perinatology (2010) 30, 688–690; doi:10.1038/jp.2010.63 Patients and methods Keywords: amniotic fluid infection; intravascular bacteria; intrauterine sepsis The patient’s chart, laboratory results, pathology report, and histopathology slides were reviewed from the medical records at Women and Infants Hospital of Rhode Island. The Institutional Review Board for Women and Infants Hospital of Rhode Island does not require Institutional Review Board approval for a physician reporting on a single case.

Introduction Pathological examination of the placenta is indicated in a wide Case range of obstetric and neonatal conditions, many of which may be A 30-year-old G2P0 woman with twin gestation was evaluated for related to an underlying infectious etiology. For instance, maternal preterm labor at 17 weeks gestational age and admitted for fever, spontaneous preterm delivery, and fetal death are frequently expectant management. An ultrasound performed a week before associated with ascending bacterial infections of the genital tract hospitalization had shown live intrauterine diamniotic- and subsequent placental infection. In developed countries, 10 to monochorionic twins and shortening of the cervix. The hospital 25% of all stillbirths appear to be caused by maternal-fetal course was complicated by premature rupture of membranes, infection. Streptococcus agalactiae (group B streptococcus; GBS), followed by the development of fever, chills, and slight abdominal Escherichia coli, and Ureaplasma urealyticum are the most tenderness. Laboratory tests were significant for leukocytosis common organisms associated with stillbirth.1 (22 000 per ml) and positive urine cultures for GBS (25 000 cfu mlÀ1). The patient was diagnosed with Correspondence: Dr F Gundogan, Department of Pathology, Women and Infants’ Hospital, chorioamnionitis and put on a triple regimen of ampicillin, 101 Dudley Street, 593 Eddy Street, Providence, RI 02905, USA. E-mail: [email protected] gentamicin, and clindamycin. After induction of labor, the patient Received 5 November 2009; revised 17 March 2010; accepted 21 March 2010 delivered two non-viable fetuses through vaginal route. Placental intravascular organisms A Matoso et al 689

Figure 1 Acute villitis and intervillitis. (a) Neutrophilic infiltrates in the villi (acute villitis, arrows). (b) Intervillositis with microabscesses (arrows). Bar, 50 m.

Figure 2 Placental intravascular organisms. (a) H&E stain of the umbilical cord vein showing the bacteria filling the lumen of the vessel (arrow). (b) Gram stain of the umbilical cord vessel showing gram-positive bacteria inside the lumen. (c) Gram stain of the chorionic plate with gram-positive bacteria inside the vessels (arrow). (d) Gram-positive bacteria were found inside the capillaries of the villi (arrow). Bar, 50 m on (a, b and d) and 100 m on (c).

The delivery was complicated by profuse bleeding. The placenta seen. Further examination revealed widespread acute villitis and was removed manually and placental culture was not performed intervillositis with numerous microabscesses (Figure 1). Large due to peripartum antibiotic treatment. No permission was given colonies of cocciform bacteria were detected within the fetal for postmortem examination. membranes. Similarly, abundant bacterial organisms were The diamniotic-monochorionic twin placenta was markedly identified within the lumen of fetal vessels in umbilical cord, fragmented and showed opaque membranes and fetal surface. The chorionic plate, and stem villi. Gram stain further characterized placental disc weighed 120 g. Velamentous insertion of one cord the organisms as gram-positive cocci, morphologically consistent was noted. Because of marked placental disruption, vascular with group B Streptococci (Figure 2). The degree of injection studies could not be performed. However, vascular chorioamnionitis was comparable on both sides of the placenta. communications between the twin circulations were readily Similarly, both sides revealed abundant gram-positive cocci in the visualized. Microscopic examination revealed mild acute fetal vessels. The chorionicity was confirmed by microscopic chorioamnionitis. There was no histopathologic evidence of examination of the (detached) dividing membrane. On the basis of associated fetal inflammatory response. Specifically, no vasculitis of the GBS-positive maternal urine cultures and the presence of the umbilical cord vessels or fetal vessels of the chorionic plate was gram-positive cocci in fetal placental vessels, the preterm labor

Journal of Perinatology Placental intravascular organisms A Matoso et al 690 and subsequent demise of the twins were attributed to intrauterine Several aspects of this case deserve further attention. First, this GBS sepsis. was a diamniotic-monochorionic twin pregnancy. As in virtually all twin gestations of this type, extensive intertwin vascular communications were present. We speculate that the GBS infection, Discussion while originally acquired by ascending infection to one twin (likely We report a case of second trimester stillbirth due to intrauterine the lower lying twin), may have spread to the co-twin through the sepsis. A conclusive diagnosis of intrauterine sepsis would normally shared circulation. Although we cannot definitively exclude the require documentation by positive postmortem blood cultures. In possibility, hematogenous spread is unlikely especially in the this case, where autopsy was declined, sepsis could nevertheless be absence of maternal sepsis. However, as prematurity is a state of demonstrated by the identification of bacterial organisms in fetal immunosuppression, bacteria escaping the maternal immune vessels in the placenta. The presence of bacteria beneath the system could still seed the placental vasculature and cause fetal epithelial layer of the amnion has been previously described in GBS sepsis. This concept requires further consideration. infections.3 In addition, in cases of GBS-induced acute villitis, Second, the placenta showed dramatic villitis and intervillositis microorganisms have been found in the capillaries of the villi.4 associated with microabscesses, which are recognized but However, organisms within large placental vessels in relation to uncommon findings in GBS infection.4 Indeed, the more common intrauterine fetal demise have not been previously reported. This features of placental involvement by GBS consist of varying degrees case stresses the importance of diligent placental examination. In of acute chorioamnionitis with fetal inflammatory response, not addition to examining the placental membranes, umbilical cord, accompanied by villitis. Villitis and intervillositis are traditionally and chorionic plate vessels to indentify and grade chorioamnionitis associated with hematogenous rather than ascending infection. In with or without inflammatory response, special attention should be this case, there was no evidence of maternal sepsis, making it paid to the contents of the fetal vasculature. Indeed, as shown in this highly unlikely that GBS was acquired hematogenously. Whether case, the presence of microbial organisms in the fetal vasculature of villitis/intervillositis in the setting of GBS infection indicate altered the placenta, even in the absence of pathologic evidence of a fetal virulence and/or altered bacteria/host interactions remains unclear. inflammatory response, may allow a definitive diagnosis of In summary, we report a case of intrauterine GBS sepsis, intrauterine sepsis. Besides, the identification of placental resulting in twin stillbirth. Despite the lack of postmortem cultures, intravascular organisms could be of critical value in cases without a definitive diagnosis of intrauterine sepsis could be made by placental cultures or with negative cultures. In cases of subclinical demonstration of bacterial organisms in the placental fetal chorioamnionitis, placental culture would not be performed. vasculature. This case emphasizes the importance of detailed Furthermore, peripartum antibiotic treatment might preclude culture placental examination with special attention to the fetal yield. In fact, Bhola et al. analyzed the role of placental cultures in vasculature, especially in cases of suspected intrauterine infection. 412 placentas submitted for histopathology in high-risk pregnancies. Of these, 63% were also submitted for microbiology culture and only Conflict of interest 4.6% had a positive culture result. Furthermore, positive placental The authors declare no conflict of interest. cultures were found in only a small number of placentas with 5 histological evidence of chorioamnionitis and funisitis. References This case of fatal intrauterine GBS infection illustrates the virulence of this organism. GBS colonization of the genital tract 1 Hood IC, Desa DJ, Whyte RK. The inflammatory response in candidal chorioamnionitis. Hum Pathol 1983; 14: 984–990. during pregnancy has been associated with premature rupture of 2 Regan JA, Klebanoff MA, Nugent RP. The epidemiology of group B streptococcal membranes and preterm labor, intra-amniotic infections, and colonization in pregnancy. Vaginal Infections and Prematurity Study Group. Obstet 6 endometritis. In a retrospective study of 129 fetuses and placentas, Gynecol 1991; 77: 604–610. GBS was the most significant pathogen associated with mid- 3 Vigorita VJ, Parmley TH. Intramembranous localization of bacteria in beta-hemolytic gestation abortion. It needs to be emphasized that GBS infection group B streptococcal chorioamnionitis. Obstet Gynecol 1979; 53: 13S–15S. does not always elicit clinical signs of chorioamnionitis,7 and it is 4 Kraus FT, Redline RW, Gersell DJ, Nelson DM, Dicke JM. Inflammation and infection. Placental pathology. In: Donald WK (ed). Atlas of Nontumoral Pathology. American not always associated with histopathologic evidence of infection. De Registry of Pathology Armed Forces Institute of Pathology: Washington, DC, 2004. Paepe et al. previously demonstrated that histopathologic pp 90–91. fetoplacental inflammation is a poor indicator of perinatal GBS 5 Bhola K, Al-Kindi H, Fadia M, Kent AL, Collignon P, Dahlstrom JE. Placental cultures in infection. In their study, only 67% of preterm and 33% of term the era of peripartum antibiotic use. Aust N Z J Obstet Gynaecol 2008; 48: 179–184. fetuses or newborns with culture-proven fatal GBS infection showed 6 Newton ER, Clark M. Group B streptococcus and preterm rupture of membranes. Obstet 7 Gynecol 1988; 71: 198–202. histologic inflammation. In cases of negative chorioamnionitis, 7 De Paepe ME, Friedman RM, Gundogan F, Pinar H, Oyer CE. The histologic routine cultures of the lungs and blood performed during fetoplacental inflammatory response in fatal perinatal group B-streptococcus infection. postmortem examination would reveal infection. J Perinatol 2004; 24: 441–445.

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