CD34 immunostain increases the sensitivity of placental diagnosis of fetal vascular malperfusion in stillbirth

Placental fetal vascular malperfusion in maternal diabetes mellitus

OBJECTIVES

To study the clinical and placental correlations in diabetic pregnancies in which placental histopathology included routine double E cadherin/CD34 immunostaining.

METHODS

Retrospective study of 229 cases of diabetic pregnancies, mostly with gestational diabetes mellitus. The cases were individually matched for gestational age at delivery with non-diabetic pregnancies to yield a comparative group of 229 cases. 23 independent clinical and 50 placental phenotypes (variables) were statistically compared by analysis of variance or Chi-square with application of the Bonferroni correction for multiple comparisons.

RESULTS

The study group showed statistically significantly more common gestational hypertension, chronic hypertension, polyhydramnios, umbilical cord compromise, cesarean sections, macerated stillbirths, neonatal deaths, and fetal malformations. About a third of cases in each group showed lesions of maternal and fetal vascular malperfusion (FVM), the latter more common than reported in literature. The CD34 component of the double immunostaining increased the sensitivity of placental examination by highlighting clustered endothelial fragmentation of recent fetal vascular malperfusion or increasing the grade of fetal vascular malperfusion (on-going distal villous fetal vascular malperfusion with temporal heterogeneity).

CONCLUSIONS

With the double immunostaining, FVM is as common as maternal vascular malperfusion pattern of placental injury in diabetic pregnancies with high prevalence of fetal congenital malformations. This is likely due to umbilical cord compression evoked by mass-forming fetal anomalies. Recognizing placental FVM may sensitize to the increased risk of neonatal systemic thrombotic pathology. However, several hypoxic lesions and patterns as well as those of shallow placental implantation were also seen with increased frequencies in diabetic pregnancies.

SARS-CoV-2 Infection during Delivery Causes Histopathological Changes in the Placenta

BACKGROUND

SARS-CoV-2 can damage human placentas, leading to pregnancy complications, such as preeclampsia and premature birth. This study investigates the histopathological changes found in COVID-19-affected placentas.

MATERIALS AND METHODS

This study included 23 placentas from patients with active COVID-19 during delivery and 22 samples from patients without COVID-19 infection in their medical history. The samples underwent histopathological examination for pathology, such as trophoblast necrosis, signs of vessel damage, or fetal vascular malperfusion.

RESULTS

Newborns from the research group have lower weights and Apgar scores than healthy newborns. In the COVID-19 group, calcifications and collapsed intervillous space were more frequent, and inflammation was more severe than in the healthy group. At the same time, the placenta of SARS-CoV-2-positive patients showed signs of accelerated vascular maturation. Trophoblast necrosis was found only in the placentas of the research group. The expression of CD68+ was elevated in the COVID-19 cohort, suggesting that macrophages constituted a significant part of the inflammatory infiltrate. The increase in lymphocyte B markers was associated with placental infarctions, while high levels of CD3+, specific for cytotoxic T lymphocytes, correlated with vascular injury.

CONCLUSIONS

SARS-CoV-2 is associated with pathological changes in the placenta, including trophoblast necrosis, calcification, and accelerated villous maturation. Those changes appear to be driven by T cells and macrophages, whose increased expression reflects ongoing histiocytic intervillositis in the placenta.

Clinical Significance of the Large Fetal Vessel Lesions in Placental Fetal Vascular Malperfusion

Fetal vascular malperfusion (FVM) is an important pattern of placental injury. Although the significance of distal villous FVM (clusters of sclerotic and/or mineralized chorionic villi) is well documented, the clinical significance of proximal (large vessel) lesions of FVM is less clear, which is the aim of this retrospective analysis. To evaluate the clinical significance and placental associations of single and coexisting categories of lesions of large vessel FVM, 24 clinical and 44 placental phenotypes of 804 consecutive placentas with at least 1 lesion of proximal vessel FVM from the second half of pregnancy, divided according to the type or category of the individual FVM lesion (fetal vascular ectasia, fetal vascular thrombi, intramural fibrin deposition, and stem vessel obliteration): 689, 341, 286, and 267 placentas, respectively (first analysis) and single or coexisting large fetal vessel lesions (1, 2, 3, and 4 coexisting categories of lesions: 276, 321, 162, and 45 placentas, respectively) were statistically compared (analysis of variance, χ2, univariate analysis). Because of multiple comparisons, Bonferroni-corrected P < .001 was used as a threshold of statistical significance. In this population of high-risk pregnancies dominated by fetal congenital anomalies, single individual or 1 to 2 coexisting categories of lesions of the large vessel FVM, including fetal vascular thrombi, did not consistently correlate with clinical or placental variables and were not prognostically useful, but the coexistence of 3 or 4 lesions was associated with the most advanced gestational age, fetal congenital anomalies, distal villous FVM, particularly high-grade, chorangioma or chorangiomatosis, hypercoiled umbilical cord, perivascular stem edema, and marginate or vallate placenta. Therefore, the finding of multiple lesions of the large vessel FVM not only merits a diligent search for the distal villous lesions including the CD34 immunostaining, but also justifies putting the large vessel (global) FVM on the final placental diagnosis line, which in the case of up to only 2 lesions may not be justified.

Placental fetal vascular malperfusion in congenital diaphragmatic hernia

The success of in-utero or intrapartum treatment for congenital diaphragmatic hernia (CDH) can be impacted by poor placental function; however, this relationship has not yet been studied. To analyze placental histomorphology in CDH, the frequencies of 24 independent clinical and 48 placental phenotypes were compared. Slides from 103 CDH placentas (group 1) and 133 clinical umbilical cord (UC) compromise/anatomical UC abnormality placentas without CDH (group 2) were subjected to hematoxylin/eosin staining and CD34 immunostaining and then examined. CD34 immunostaining was performed to identify clustered distal villi with endothelial fragmentation of recent fetal vascular malperfusion (FVM). Cesarean delivery and ex utero intrapartum treatment were more common in group 1, but group 2 showed a higher frequency of statistically significant increases in other clinical phenotypes. The frequencies of large vessels and distal villous FVMs (clustered endothelial fragmentation by CD34 immunostaining, stromal vascular karyorrhexis, avascular, or mineralized villi) did not differ between the groups, but low-grade distal villous FVMs were statistically significantly more common in group 1 than in group 2, while high-grade distal villous FVMs were significantly more common in group 2 than group 1. Large vessel and distal villous FVMs were manyfold more common in both the CDH and UC compromise groups than in the general population. However, CDH placentas were more likely to show low-grade distal villous FVMs and less likely to show high-grade distal villous FVMs in UC compromise placentas. FVM of CDH may therefore be caused by a similar pathomechanism as that of UC compromise, resulting in impaired placental fetal blood outflow.

Single Umbilical Artery Umbilical Cord Is Associated With High-Grade Distal Fetal Vascular Malperfusion

PURPOSE AND CONTEXT

Umbilical cord abnormalities with clinical signs of cord compromise are frequently associated with fetal vascular malperfusion (FVM). Single umbilical artery (SUA) has been reported to be associated with high-grade FVM in fetal growth restriction but not in an unselected population; our study aimed to address this issue.

METHODS

Clinical and placental phenotypes of 55 consecutive placentas with SUA (Group 1) were compared with those of 655 placentas with 3-vessel umbilical cord (Group 2) from patients who were in the second half of their pregnancy. The placentas were histologically examined using hematoxylin and eosin (H&E) staining and CD 34 immunostaining.

KEY RESULTS

Several umbilical cord phenotypes and high-grade distal FVM, based on H&E staining and endothelial fragmentation by CD34 were significantly more common in Group 1, whereas decidual clusters of multinucleate trophoblasts were more common in Group 2. Notably, H&E staining or CD34 immunostaining evaluated separately showed that high-grade distal FVM was more common in Group 1 than in Group 2, but the difference was not statistically significant.

CONCLUSIONS

SUA predisposes to remote, advanced, and recent high-grade distal villous FVM, with a pathogenesis partly different from that of stasis-induced FVM, likely related to fetal anomalies associated with SUA.

Fetal vascular malperfusion score is linked with developing preeclampsia in women with gestational diabetes mellitus: a retrospective cohort study

OBJECTIVE

Fetal vascular malperfusion is associated with poor perinatal outcomes in women with preeclampsia and gestational diabetes mellitus. The aim of this study was to determine the association between fetal vascular malperfusion score and syncytiotrophoblast basement membrane thickness and clinicopathological variables, such as developing preeclampsia in women with gestational diabetes mellitus.

METHODS

This retrospective cohort study included 65 pregnant participants (34 with gestational diabetes mellitus and 31 controls) between January 2019 and January 2022. Gestational diabetes mellitus was diagnosed as ≥2 of 4 elevated values on a 3-h, 100-g oral glucose tolerance test. The fetal vascular malperfusion score was evaluated by endothelial CD34 positivity in the villous stroma of the placenta. The association between fetal vascular malperfusion score and syncytiotrophoblast basement membrane thickness with clinicopathological variables in women with gestational diabetes mellitus was evaluated.

RESULTS

It was revealed that the gestational diabetes mellitus group had greater fetal vascular malperfusion scores than the control group (gestational diabetes mellitus group fetal vascular malperfusion score: 34.2±9.1 and control group fetal vascular malperfusion score: 26.5±8.7, respectively, p=0.0009). Syncytiotrophoblast basement membrane thickness was correlated with the development of preeclampsia, trophoblast proliferation, and fetal vascular malperfusions (0.3952, p=0.0129; 0.3487, p=0.0211; and 0.4331, p=0.0082, respectively). On the contrary, fetal vascular malperfusions were correlated with the development of preeclampsia, villous edema, and trophoblast proliferation (0.3154, p=0.0343; 0.2922, p=0.4123; and 0.3142, p=0.0355, respectively).

CONCLUSION

The gestational diabetes mellitus group displayed significantly higher fetal vascular malperfusion scores and thickening of the syncytiotrophoblast basement membrane than the control group. There is a correlation between developing preeclampsia and the fetal vascular malperfusion scores and the syncytiotrophoblast basement membrane thickness.

CD34 immunostain increases the sensitivity of placental examination for distal fetal vascular malperfusion in liveborn infants

INTRODUCTION

Placental fetal vascular malperfusion (FVM) is associated with increased perinatal morbidity and mortality. This retrospective observational analysis was performed to compare the impact of large proximal vessel (global) FVM, established/remote distal villous FVM, and recent (acute) FVM diagnosed by clustered endothelial fragmentation by CD34 immunostaining, on clinical and other placental phenotypes.

METHODS

Clinical and placental phenotypes of 581 consecutive high-risk pregnancies with a live birth divided in five groups based on presence and type of FVM were analyzed. CD34 immunostaining was performed on all cases to refine the diagnosis of FVM. The statistical analysis was by ANOVA and Chi square.

RESULTS

FVM was present in 88% of placentas from pregnancies dominated by congenital anomalies. 43% of those had global FVM (partial, large proximal vessel) without distal villous changes, either acute (endothelial fragmentation) or established (avascular villi). Acute distal villous FVM without avascular villi did not link with significant perinatal morbidity/mortality, likely because of its short duration. Established distal villous FVM with active endothelial fragmentation, labelled as FVM with temporal heterogeneity, is associated with preterm births, preeclampsia, abnormal Dopplers, fetal growth restriction, highest cesarean section rate, and high grade FVM, particularly the latter.

DISCUSSION

Lesions of global FVM are common, featuring relatively low sensitivity for perinatal complications. Caution is indicated in assigning significance to isolated lesions such as fetal vascular ectasia, intramural fibrin deposition and stem vessel obliteration. Established and on-going FVM diagnosed by using CD34 immunostain, is much more significant and portends the most complicated perinatal outcomes.

Shallow Placentation: A Distinct Category of Placental Lesions

OBJECTIVE

Shallow placental implantation (SPI) features placental maldistribution of extravillous trophoblasts and includes excessive amount of extravillous trophoblasts, chorionic microcysts in the membranes and chorionic disc, and decidual clusters of multinucleate trophoblasts. The histological lesions were previously and individually reported in association with various clinical and placental abnormalities. This retrospective statistical analysis of a large placental database from high-risk pregnancy statistically compares placentas with and without a composite group of features of SPI.

STUDY DESIGN

Twenty-four independent abnormal clinical and 44 other than SPI placental phenotypes were compared between 4,930 placentas without (group 1) and 1,283 placentas with one or more histological features of SPI (composite SPI group; group 2). Placentas were received for pathology examination at a discretion of obstetricians. Placental lesion terminology was consistent with the Amsterdam criteria, with addition of other lesions described more recently.

RESULTS

Cases of group 2 featured statistically and significantly (p < 0.001after Bonferroni's correction) more common than group 1 on the following measures: gestational hypertension, preeclampsia, oligohydramnios, polyhydramnios, abnormal Dopplers, induction of labor, cesarean section, perinatal mortality, fetal growth restriction, stay in neonatal intensive care unit (NICU), congenital malformation, deep meconium penetration, intravillous hemorrhage, villous infarction, membrane laminar necrosis, fetal blood erythroblastosis, decidual arteriopathy (hypertrophic and atherosis), chronic hypoxic injury (uterine and postuterine), intervillous thrombus, segmental and global fetal vascular malperfusion, various umbilical cord abnormalities, and basal plate myometrial fibers.

CONCLUSION

SPI placentas were statistically and significantly associated with 48% abnormal independent clinical and 51% independent abnormal placental phenotypes such as acute and chronic hypoxic lesions, fetal vascular malperfusion, umbilical cord abnormalities, and basal plate myometrial fibers among others. Therefore, SPI should be regarded as a category of placental lesions related to maternal vascular malperfusion and the "Great Obstetrical Syndromes."

KEY POINTS

· SPI reflects abnormal distribution of extravillous trophoblasts.. · SPI features abnormal clinical and placental phenotypes.. · SPI portends increased risk of complicated perinatal outcome..

Anti-TPO-mediated specific features of the placenta immunohistochemical profile and possible mechanisms for fetal loss

Passive transfer of antithyroid antibodies in mice leads to reproductive disorders. The purpose was to assess the placental tissue of experimental animals under the influence of the circulating thyroperoxidase antibodies. We performed an immunohistochemical examination of murine placentae after a passive transfer of thyroperoxidase antibodies. Placentae of mice that passively transferred IgG from healthy donors were used as control samples. For histological examination, 30 placental samples were selected from mice from the anti-TPO group and 40 placental samples were taken from mice from the IgG group. Immunostaining for VEGFR1, THBS 1, Laminin, CD31, CD34, FGF-β, CD56, CD14, TNF-α, kisspeptin, MCL 1, and Annexin V was performed. There is a significant decrease in the relative area of the expression of VEGFR1 (23.42 ± 0.85 vs. 33.44 ± 0.35, P < 0.01), thrombospondin 1 (31.29 ± 0.83 vs. 34.51 ± 0.75, P < 0.01), CD14 (25.80 ± 0.57 vs. 32.07 ± 0.36, P < .01), CD56 (30.08 ± 0.90 vs. 34.92 ± 0.15, P < 0.01), kisspeptin (25.94 ± 0.47 vs. 31.27 ± 0.57, P < 0.01), MCL 1 (29.24 ± 1.06 vs. 38.57 ± 0.79, P < 0.01) in the labyrinth zone of the placentae of mice from the anti-TPO group compared with control group. A significant increase in the relative expression of laminin and FGF-β was noted in the group of mice to which antibodies to thyroperoxidase were transferred, compared with the control group (36.73 ± 1.38 vs. 29.83 ± 0.94, P < 0.01 and 23.26 ± 0.61 vs. 16.38 ± 1.01, P < 0.01respectively). Our study exposed an imbalance of pro- and anti-angiogenic factors, decreased representation of placental macrophages and NK cells, abnormal trophoblast invasion processes, and insufficient expression of antiapoptotic factors in the placentae of mice in which anti-TPO antibodies were passively transferred.

Cesarean section per se is not a risk factor for non-anatomical placenta creta

OBJECTIVE

To investigate whether mild forms of placenta creta (MPC) are more common in placentas delivered by cesarean section for non-anatomical indications than in placentas from vaginal deliveries.

METHODS

This is a retrospective clinical study in which MPC was diagnosed histologically by the presence of myometrial fibers in the decidua basalis or parietalis or in direct contact with the Rohr fibrinoid or chorionic villi. After excluding 111 cases at high risk for anatomical PC, placentas from 830 consecutive cesarean deliveries (group 1) were retrospectively statistically compared with 907 placentas from vaginal deliveries (group 2).

RESULTS

Statistically significant differences were found in six independent clinical and seven placental phenotypes. More frequently, pre-eclampsia, abnormal fetal heart rate tracing and umbilical artery Dopplers, hypercoiled umbilical cord, diffuse postuterine pattern of chronic hypoxic placental injury, and clusters of avascular or mineralized chorionic villi were found in group 1, while preterm delivery, induction of labor, and histological patterns related to stillbirth were observed in group 2.

CONCLUSION

MPC diagnosed in placentas from cesarean sections performed for non-anatomical indications is not statistically significantly more common than in those after vaginal delivery. Therefore, MPC may feature similar diagnostic correlations and portend a similar prognosis for future pregnancies.

Placental pathology is necessary to understand common pregnancy complications and achieve an improved taxonomy of obstetrical disease

The importance of a fully functioning placenta for a good pregnancy outcome is unquestioned. Loss of function can lead to pregnancy complications and is often detected by a thorough placental pathologic examination. Placental pathology has advanced the science and practice of obstetrics and neonatal-perinatal medicine by classifying diseases according to underlying biology and specific patterns of injury. Many past obstacles have limited the incorporation of placental findings into both clinical studies and day-to-day practice. Limitations have included variability in the nomenclature used to describe placental lesions, a shortage of perinatal pathologists fully competent to analyze placental specimens, and a troubling lack of understanding of placental diagnoses by clinicians. However, the potential use of placental pathology for phenotypic classification, improved understanding of the biology of adverse pregnancy outcomes, the development of treatment and prevention, and patient counseling has never been greater. This review, written partly in response to a recent critique published in a major obstetrics-gynecology journal, reexamines the role of placental pathology by reviewing current concepts of biology; explaining the most recent terminology; emphasizing the usefulness of specific diagnoses for obstetrician-gynecologists, neonatologists, and patients; previewing upcoming changes in recommendations for placental submission; and suggesting future improvements. These improvements should include further consideration of overall healthcare costs, cost-effectiveness, the clinical value added of placental assessment, improvements in placental pathology education and practice, and leveraging of placental pathology to identify new biomarkers of disease and evaluate novel therapies tailored to specific clinicopathologic phenotypes of both women and infants.

Patterns of placental injury in various types of fetal congenital heart disease

OBJECTIVES

Fetal blood circulation may be modified in congenital heart disease (CHD). This retrospective analysis was performed to study whether the type of CHD is associated with specific placental pathology.

METHODS

3 types of CHD based on presumed proportion of placental and systemic blood distribution in fetal circulation were analyzed: Group 1: 89 cases with low placental blood content (hypoplastic left heart syndrome, transposition of great arteries, coarctation of aorta), Group 2: 71 placentas with intermediate placental and systemic blood content due to increased intracardiac blood mixing (tetralogy of Fallot, truncus arteriosus, double inlet/outlet ventricle), and Group 3: 24 placentas with high placental blood content (tricuspid or pulmonary atresia, Ebstein anomaly). Frequencies of 27 independent clinical and 47 placental phenotypes of 184 placentas in those three groups were statistically compared.

RESULTS

The most advanced gestational age at delivery, and large vessel (global) fetal vascular malperfusion (FVM) were most common in Group 1, while macerated stillbirths, neonatal mortality, abnormal amniotic fluid volume (oligohydramnios or polyhydramnios), other congenital anomalies, distal villous lesions of FVM, placental edema and amnion nodosum were most common in Groups 2 and 3, although the frequencies of placental lesions were statistically not significant.

CONCLUSIONS

Left heart obstructive lesions potentially associated with brain maldevelopment show increase in lesions of global FVM (in aggregate and individually fetal vascular ectasia, stem vessel obliteration and intramural fibrin deposition) as may be seen in umbilical cord compromise. CHD with increased intracardiac blood mixing or with right heart defects is associated with average preterm gestational age at delivery and placental lesions of distal villous FVM, villous edema and amnion nodosum.

Gestational exposure to PCB-118 impairs placental angiogenesis and fetal growth

Maternal exposure to polychlorinated biphenyls (PCBs) results in adverse effects on fetal development. However, the underlying mechanism has not been sufficiently explored in respect to particular PCBs. Placental angiogenesis plays a crucial role in feto-maternal substances transportation and fetal development. The present study was conducted to investigate the effects of prenatal PCB118 exposure on placental angiogenesis and fetal growth. The pregnant dam received PCB118 at environmentally relevant doses (0, 20, or 100 μg/kg/day) intragastrically from gestational day (GD) 7.5-18.5 to establish an in vivo model. Compared with the control group, the fetal body and placental weights of the PCB118 (100 μg/kg/day) group were significantly decreased and the intrauterine growth retardation (IUGR) rates were increased both in the female and male fetus. Furthermore, we found that placental histology was significantly impaired and the number of blood vessels was decreased in the PCB118 group. Additionally, gestational exposure to PCB118 caused anomalous mRNA expression of the genes in the placenta regarding angiogenesis. These findings indicate that PCB118 may contribute to the occurrence of IUGR by provoking placental angiogenesis dysfunction. This study clarified the adverse effects and potential mechanism of prenatal PCBs exposure on fetal growth, providing a new theoretical and experimental basis for future treatment and prevention.

CD34 immunostain increases sensitivity of the diagnosis of fetal vascular malperfusion in placentas from ex-utero intrapartum treatment

OBJECTIVES

EXIT (ex-utero intrapartum treatment) procedure is a fetal survival-increasing modification of cesarean section. Previously we found an increase incidence of fetal vascular malperfusion (FVM) in placentas from EXIT procedures which indicates the underlying stasis of fetal blood flow in such cases. This retrospective analysis analyzes the impact of the recently introduced CD34 immunostain for the FVM diagnosis in placentas from EXIT procedures.

METHODS

A total of 105 placentas from EXIT procedures (48 to airway, 43 to ECMO and 14 to resection) were studied. In 73 older cases, the placental histological diagnosis of segmental FVM was made on H&E stained placental sections only (segmental villous avascularity) (Group 1), while in 32 most recent cases, the CD34 component of a double E-cadherin/CD34 immunostain slides was also routinely used to detect the early FVM (endothelial fragmentation, villous hypovascularity) (Group 2). Twenty-three clinical and 47 independent placental phenotypes were compared by χ² or ANOVA, where appropriate.

RESULTS

There was no statistical significance between the groups in rates of segmental villous avascularity (29 vs. 34%), but performing CD34 immunostain resulted in adding and/or upgrading 12 more cases of segmental FVM in Group 2, thus increasing the sensitivity of placental examination for FVM by 37%. There were no other statistically significantly differences in clinical (except for congenital diaphragmatic hernias statistically significantly more common in Group 2, 34 vs. 56%, p=0.03) and placental phenotypes, proving the otherwise comparability of the groups.

CONCLUSIONS

The use of CD34 immunostain increases the sensitivity of placental examination for FVM by 1/3, which may improve the neonatal management by revealing the increased likelihood of the potentially life-threatening neonatal complications.

Placenta Creta: A Spectrum of Lesions Associated with Shallow Placental Implantation

Background

On placental histology, placenta creta (PC) ranges from clinical placenta percreta through placenta increta and accreta (clinical and occult) to myometrial fibers with intervening decidua. This retrospective study aimed to investigate the clinicopathologic correlations of these lesions.

Methods

A total of 169 recent consecutive cases with PC (group 1) were compared with 1661 cases without PC examined during the same period (group 2). The frequencies of 25 independent clinical and 40 placental phenotypes were statistically compared between the groups using chi-square test or analysis of variance where appropriate.

Results

Group 1 placentas, as compared with group 2 placentas, were statistically significantly (p < 0.05) associated with caesarean sections (11.2% vs. 7.5%), antepartum hemorrhage (17.7% vs 11.6.%), gestational hypertension (11.2% vs 4.3%), preeclampsia (11.8% vs 2.6%), complicated third stage of labor (18.9% vs 6.4%), villous infarction (14.2% vs 8.9%), chronic hypoxic patterns of placental injury, particularly the uterine pattern (14.8%, vs 9.6%), massive perivillous fibrin deposition (9.5% vs 5.3%), chorionic disc chorionic microcysts (21.9% vs 15.9%), clusters of maternal floor multinucleate trophoblasts (27.8% vs 21.2%), excessive trophoblasts of chorionic disc (24.3% vs 17.3%), segmental fetal vascular malperfusion (27.8% vs 19.9%), and fetal vascular ectasia (26.2% vs 15.2%).

Conclusion

Because of the association of PC with gestational hypertensive diseases, acute and chronic placental hypoxic lesions, increased extravillous trophoblasts in the chorionic disc, chorionic microcysts, and maternal floor trophoblastic giant cells, PC should be regarded as a lesion of abnormal placental implantation and abnormal trophoblast invasion rather than decidual deficiency only.

Temporal heterogeneity of placental segmental fetal vascular malperfusion: timing but not etiopathogenesis

Clinicopathologic correlations of segmental villous avascularity and other histological lesions of segmental fetal vascular malperfusion (SFVM) were analyzed retrospectively to determine whether lesions of various durations reflect different etiopathogeneses. The frequencies of 25 independent clinical and 43 placental phenotypes were statistically compared by ANOVA or Chi-square among 3 groups containing a total of 378 placentas with SFVM: group 1 contained 44 cases of recent SFVM (endothelial fragmentation, villous hypovascularity by CD34 immunostain, and/or stromal vascular karyorrhexis); group 2 contained 264 cases of established SFVM (clusters of avascular villi); and group 3 contained 70 cases of remote SFVM (villous mineralization). Statistically significant differences among the three study groups (p Bonferroni < 0.002) were found in four clinical variables (gestational age, frequencies of macerated stillbirth, induction of labor, and cesarean section) and in five placental variables (frequencies of fetal vascular ectasia, stem vessel luminal vascular abnormalities, diffusely increased extracellular matrix in chorionic villi, chorionic disk extravillous trophoblast microcysts, and excessive extravillous trophoblasts in the chorionic disc). In summary, the absence of statistically significant differences between the study groups regarding the most common causes of SFVM (hypertensive conditions of pregnancy, diabetes mellitus, fetal anomalies, and clinical and pathological features of umbilical cord compromise) is evidence that the three types of SFVM reflect temporal heterogeneity rather than etiopathogenesis. This evidence can be used to date the onset of fetal vascular malperfusion before delivery or stillbirth. The coexistence of different SVFM lesions of various durations indicates ongoing or repeat occurrences of FVM rather than single episodes.

Preparation of complex microcapsules of soluble polysaccharide from Glycyrrhiza uralensis and its application in wound repair and scar inhibition

The extraction process of Glycyrrhiza soluble polysaccharide (GP) was optimized by RSM, a rat trauma model was established via longitudinal incision on the back skin. The effects of GP combined with microcapsule collagen on the repair of rat injury model were discussed at different levels, Based on the content of hydroxyproline at the whole animal level, the proliferation of granulation tissue stained by HE, the number of microvessels labeled by CD34, the production of collagen fibers stained by Masson, the level of phosphorylation of STAT3 protein and that of VEGF at protein level were investigated. The results showed that after the administration of GP combined with microcapsules, the content of hydroxyproline in granulation tissue increased, the proliferation of capillaries and fibroblasts in granulation tissue became active, and the number of microvessels in wound increased. The formation density of collagen fibers was uniform and orderly. GP combined with microcapsules could activate the expression of p-STAT3 and VEGF proteins and up-regulate the transcription level of VEGF mRNA and miRNA-21 genes. Furthermore, GP combined with microcapsules could accelerate wound healing and promote neovascularization.

Patterns of Placental Injury in Congenital Anomalies in Second Half of Pregnancy

BACKGROUND

Placental pathology in fetal congenital anomalies in second half of pregnancy is largely unknown.

METHODS

Twenty-six clinical and 45 independent placental phenotypes from pregnancies ≥20 weeks of gestation with congenital anomalies divided into 4 groups were retrospectively compared with analysis of variance or χ ² with 3 degrees of freedom and with Bonferroni correction for multiple comparisons: group 1 : 112 cases with heart malformations (with or without chromosomal anomalies), group 2 : 41 cases with abnormal karyotypes and anomalies other than heart malformations, group 3 : 87 cases with intrathoracic or intraabdominal mass-forming anomalies (mostly congenital diaphragmatic hernias and adenomatoid airway malformation), and group 4 : 291 miscellaneous cases with mostly skeletal, renal, and central nervous system anomalies not fulfilling the criteria of inclusion into groups 1 to 3.

RESULTS

Eight of 26 clinical (30.8%) and 16 of 45 (35.5%) placental phenotypes varied statistically significantly among the 4 groups (P <  .05), of those, 7 (26.9%) and 4 (8.9%), respectively, remained statistically significant after Bonferroni correction (P Bonferroni ≤  .002). Those placental phenotypes were placental weight, chorionic disc chorionic microcysts, fetal vascular ectasia, and luminal vascular abnormalities of chorionic villi.

CONCLUSIONS

Fetal anomalies in second half of pregnancy feature abnormal clinical phenotypes much more frequently than abnormal placental phenotypes. Chromosomal abnormalities with or without heart malformations tend to feature villous edema, and erythroblastosis of fetal blood, likely due to fetal heart failure. Mass-forming fetal anomalies feature placental histological lesions of shallow placental implantation, diffuse chronic hypoxic patterns of placental injury, and lesions of fetal vascular malperfusion, likely stasis-induced.

Segmental villous mineralization: A placental feature of fetal vascular malperfusion

INTRODUCTION

This retrospective analysis was performed to find out if clusters of mineralized chorionic villi can be regarded as an independent feature of fetal vascular malperfusion (FVM).

METHODS

Of all 1698 placentas reviewed by the author during the last 10 years, 39 (2.3%) showed clusters of mineralized chorionic villi (Group 1), 100 cases (5.9%) showed randomly scattered mineralized chorionic villi with without clustering (Group 2), and the remaining 1559 placentas showed no villous mineralization (comparative Group 3). In doubtful cases, histochemistry stains were performed to determine the pattern of villous mineralization. Twenty three independent clinical and 43 placental variables were statistically compared among the groups: descriptive statistics (Chi-square, Fisher test or signed rank test), and logistics regression model.

RESULTS

Clinically, Group 1 featured shorter gestational age than Group 2, and in addition to shorter gestational age, more common oligohydramnios, polyhydramnios, induction of labor, macerated stillbirth and fetal growth restriction than Group 3. Of placental variables, fetal vascular ectasia, and clusters of avascular chorionic villi were more common in Group 1 than in Group 2, and in addition, segmental villous stromal vascular karyorrhexis was more common than in Group 3. By the logistics regression mode, segmental villous mineralization was independently associated with other histological features of FVM as a group and particularly with clusters of sclerotic chorionic villi.

DISCUSSION

FVM is characterized by temporal heterogeneity, i.e. coexistence of lesions of various duration, and strongly and independently correlates with clusters of mineralized chorionic villi. Therefore, segmental villous mineralization should be included into the category of segmental FVM. It can be seen even in totally fibrotic placentas of prolonged stillbirth when other histological features of segmental vascular malperfusion can be obscured by global villous sclerosis.