Heerema-McKenney Amy
Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH, USA.
APMIS. 2018 Jul;126(7):570-588. doi: 10.1111/apm.12847.
The placenta functions as a shield against infection of the fetus. The innate and adaptive immune defenses of the developing fetus are poorly equipped to fight infections. Infection by bacteria, viruses, and protozoa may cause infertility, spontaneous abortion, stillbirth, growth retardation, anomalies of development, premature delivery, neonatal morbidity, and mortality. However, appreciation of the human microbiome and host cell-microbe interactions must be taken into consideration as we try to determine what interactions are pathologic. Infection is typically recognized histologically by the presence of inflammation. Yet, several factors make comparison of the placenta to other human organs difficult. The placenta comprises tissues from two persons, complicating the role of the immune system. The placenta is a temporary organ. It must be eventually expelled; the processes leading to partuition involve maternal inflammation. What is normal or pathologic may be a function of timing or extent of the process. We now must consider whether bacteria, and even some viruses, are useful commensals or pathogens. Still, recognizing infection of the placenta is one of the most important contributions placental pathologic examination can give to care of the mother and neonate. This review provides a brief overview of placental defense against infection, consideration of the placental microbiome, routes of infection, and the histopathology of amniotic fluid infection and TORCH infections.
胎盘起到保护胎儿免受感染的屏障作用。发育中的胎儿的先天和适应性免疫防御能力较弱，难以抵抗感染。细菌、病毒和原生动物感染可能导致不孕、自然流产、死产、生长发育迟缓、发育异常、早产、新生儿发病和死亡。然而，在我们试图确定哪些相互作用是病理性的时候，必须考虑到人类微生物组和宿主细胞与微生物的相互作用。感染通常在组织学上通过炎症的存在来识别。然而，有几个因素使得将胎盘与其他人体器官进行比较变得困难。胎盘由来自两个人的组织组成，这使得免疫系统的作用变得复杂。胎盘是一个临时器官。它最终必须被排出；导致分娩的过程涉及母体炎症。正常或病理性可能是该过程的时间或程度的函数。我们现在必须考虑细菌，甚至一些病毒，是有益的共生菌还是病原体。尽管如此，识别胎盘感染是胎盘病理检查对母亲和新生儿护理最重要的贡献之一。本综述简要概述了胎盘对感染的防御、胎盘微生物组的考量、感染途径以及羊水感染和TORCH感染的组织病理学。
