Clinically relevant umbilical cord inflammation identified based on CD15-associated vasculitis patterning

The Molecular and Histopathological Assessment of Inflammatory Status in Very and Extremely Premature Infants: A Prospective Study

Prematurity comes with a varying range of complications, implying a high prevalence of complications and mortality and depending on the severity of prematurity and the sustained inflammation among these infants, which recently sparked an important scientific interest. The primary objective of this prospective study was to establish the degree of inflammation in very (VPIs) and extremely preterm infants (EPIs) in association with the histology findings of the umbilical cord (UC), while the secondary objective was to study the inflammatory markers in the neonates' blood as predictors of fetal inflammatory response (FIR). A total of thirty neonates were analyzed, ten of them being born extremely premature (<28 weeks of gestation) and twenty very premature (28-32 weeks of gestation). The EPIs had considerably higher levels of IL-6 at birth than VPIs (638.2 pg/mL vs. 151.1 pg/mL). The CRP levels at delivery did not vary substantially across groups; however, after days, the EPIs had significantly higher CRP levels (11.0 mg/dL vs. 7.2 mg/dL). In contrast, the LDH was considerably higher in the extremely preterm infants at birth and four days after birth. Surprisingly, the proportions of infants with pathologically increased inflammatory markers did not differ between the EPIs and VPIs. The LDH increased considerably in both groups, although the CRP levels increased exclusively among the VPIs. The stage of inflammation in the UC did not vary substantially between the EPIs and VPIs. The majority of infants were identified with Stage 0 UC inflammation (40% in EPI vs. 55% in VPIs). There was a substantial correlation link between gestational age and newborn weight and a significant inverse correlation among gestational age and IL-6 and LDH levels. There was a strong negative association between weight and IL-6 (rho = -0.349) and LDH (rho = -0.261). The stage of the UC inflammation demonstrated a statistically significant direct connection with IL-6 (rho = 0.461) and LDH (rho = 0.293), but none with the CRP. Further studies involving a bigger population size of preterm newborns are required to validate the findings and analyze more inflammatory markers, while prediction models on inflammatory markers that are measured expectantly, before the onset of preterm labor, need to be created.

COVID-19 in pregnancy: placental pathological patterns and effect on perinatal outcome in five cases

INTRODUCTION

COVID-19, the disease caused by the novel coronavirus SARS-CoV-2, is a severe systemic thrombotic syndrome that emerged in 2019, with an ensuing pandemic. To evaluate the impact of this disease on placental tissue and perinatal outcome, histological, immunohistochemical and ultrastructural analyses of placental tissue were performed for five cases of pregnant women with COVID-19.

CASE REPORTS

All five pregnant women in this series developed COVID-19 in late pregnancy. Two patients experienced respiratory distress, and computed tomography revealed signs of pneumonia, with bilateral involvement, multiple lobular and subsegmental areas of consolidation and ground-glass opacities. Histological studies of placental tissue revealed the presence of slight signs of maternal vascular underperfusion (MVUs) or foetal vascular underperfusion (FVUs) lesions and mild inflammatory lesions. CD15 immunoreactivity in the placental tissue was low in all cases, demonstrating that in these cases there was not severe foetal hypoxia/asphyxia risk for newborns or distal vascular immaturity. In all cases examined, ultrastructural analyses showed spherical-like coronavirus particles with an electron intermediate-density core as well as projections from the surface as spike-like structures in the syncytiotrophoblasts. At term, all of the women delivered newborns who were negative for SARS-CoV-2 by nasopharyngeal testing in their first day of life. All newborns were exclusively breastfed and were discharged on the 3rd day of life.

CONCLUSIONS

In conclusion, placental patterns in pregnancy due to COVID-19 in the late stage of gestation indicate no evidence of vertical trans-placental SARS-CoV-2 transmission or a significant impact on the perinatal outcome of newborns, in both mild and more severe cases.

Characterization of vitelline vessel remnant circulation in the umbilical cord

The vitelline circulation normally regresses by about 10 weeks gestation. Vitelline vessel remnants (VVRs) are found in approximately 4-11% of umbilical cords. While these remnants retain an active fetal circulation, this has never been studied. Using an operating microscope, VVRs were catheterized, injected with ink, and then examined grossly and histologically. Over 90% of VVRs are paired thin-walled vessels with afferent and efferent circulation completed within the cord via capillary plexuses and bridging vessels; <10% are single thin-walled arterial vessels running the length of the cord to the placental disc, with their venous return circulation via allantoic umbilical vessels.