Antenatal diagnosis of chorioamnionitis: A review of the potential role of fetal and placental imaging

Abstract

Chorioamnionitis is present in up to 70% of spontaneous preterm births. It is defined as an acute inflammation of the chorion, with or without involvement of the amnion, and is evidence of a maternal immunological response to infection. A fetal inflammatory response can coexist and is diagnosed on placental histopathology postnatally. Fetal inflammatory response syndrome (FIRS) is associated with poorer fetal and neonatal outcomes. The only antenatal diagnostic test is amniocentesis which carries risks of miscarriage or preterm birth. Imaging of the fetal immune system, in particular the thymus and the spleen, and the placenta may give valuable information antenatally regarding the diagnosis of fetal inflammatory response.While ultrasound is largely limited to structural information, MRI can complement this with functional information that may provide insight into the metabolic activities of the fetal immune system and placenta. This review discusses fetal and placental imaging in pregnancies complicated by chorioamnionitis and their potential future use in achieving non-invasive antenatal diagnosis. Key points What's already known about the topic?� Chorioamnionitis is present in up to 70% of spontaneous preterm births and is associated with more complications than unaffected spontaneous preterm births � Diagnosis is postnatal. Antenatal diagnosis by amniocentesis carries a risk of preterm birth, and is not integrated into clinical care What does this review add?� Ultrasound assessment of the fetal immune system gives structural information and limited functional information, while MRI can complement this with greater functional tissue information � Imaging may play a role in the non-invasive antenatal diagnosis of chorioamnionitisThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Blood products transfusion and retinopathy of prematurity: A cohort study

“…Chorioamnionitis is acute inf lammation of the chorion with or without involvement of the amnion and is evidence of a maternal immunological response to infection, with a history of foul-smelling amniotic f luid, fever, increased acute-phase reactants and/or spontaneous onset preterm labour (Hall et al, 2022).…”

Risk of adverse perinatal outcomes among women with clinical and subclinical histopathological chorioamnionitis

“…These findings suggest that NLR could serve as a useful biomarker for identifying women at risk of chorioamnionitis and potentially aid in clinical decision-making ( 48 ). Imaging of the fetal immune system, in particular the thymus and the spleen, and the placenta may give valuable information antenatally regarding the diagnosis of fetal inflammatory response ( 49 ).…”

Síndrome de respuesta inflamatoria fetal: aproximación ultrasonográfica

“…Sin embargo, en la práctica clínica pareciera que la sensibilidad de marcadores ultrasonográficos específicos de las diversas etapas de funisitis y su relación con corioamnionitis histológica es baja para la detección de fetos en riesgo de FIRS, ya que se limitan a reportes de casos aislados (28)(29)(30). Por ello, la utilización de marcadores indirectos de FIRS en relación a cambios histopatológicos en placenta y órganos blanco es más plausible que mejore la detección de fetos en riesgo de FIRS (2,3,6,24,31,32).…”

“…Por ende, además de considerar el estudio histopatológico placentario y el uso de marcadores inflamatorios como la IL-6, la PCR y la procalcitonina postnatales, es necesaria la investigación clínica e implementación basada en la evidencia de marcadores ultrasonográficos prenatales para el diagnóstico de FIRS. Entre los órganos en los que se han descrito marcadores ultrasonográficos de FIRS tenemos, corazón, timo, bazo, glándulas suprarrenales y riñones (2,3,6,24,31).…”