Placental mesenchymal dysplasia with severe fetal growth restriction in one placenta of a dichorionic diamniotic twin pregnancy

Localized Placental Mesenchymal Dysplasia in Monochorionic Diamniotic Twin Placenta with Beckwith-Wiedemann Syndrome

IntroductionPlacental mesenchymal dysplasia (PMD) is often associated with Beckwith-Wiedemann syndrome. Case report: A 27-year-old woman with preeclampsia prematurely delivered twin girls. One side of the placenta was larger with numerous grape-like vesicles, histologically with large, cystic, stem villi with cisterns without syncytiotrophoblastic hyperplasia. This side showed mosaicism for chromosome 11 by FISH and hypomethylation at ICR2 by MLPA. The smaller side of the placenta was normal macroscopically, microscopically, and karyotypically. There was symmetric growth restriction, macroglossia and hypoglycemia of the girl corresponding to the abnormal placental side, and lesser symmetric growth restriction and mild hypoglycemia in the other girl. Conclusion: Localized placental mesenchymal dysplasia can occur in monochorionic diamniotic twin placenta with Beckwith-Wiedemann syndrome. Fetal affects may be asymmetric. PMD can be associated with mosaicism monosomy of chromosome 11.

A Challenging Diagnosis: Placental Mesenchymal Dysplasia—Literature Review and Case Report

We describe a 22-year-old woman (2-gravid) case who was referred to our clinic at 18 weeks of gestation for a placenta with vesicular lesions discovered on prenatal examination routine. An ultrasound exam at 31 weeks of gestation showed numerous vesicular lesions, which gradually augmented as the pregnancy advanced. A live normal-appearing fetus was confirmed by intrauterine growth restriction (IUGR). The maternal serum β-human chorionic gonadotropin level remained in normal ranges. At some point, a multidisciplinary medical consensus considered the termination of the pregnancy, but the patient refused to comply. At 33 weeks of gestation, preterm premature rupture of membranes (pPROM) occurred, and she spontaneously delivered a 1600 g healthy female baby with a good long-term outcome. Placental mesenchymal dysplasia (PMD) was retrospectively diagnosed after confronting the data from ultrasound, chorionic villus sampling (CVS), amniocentesis, pathological examination, and immunohistochemical stain. The lack of sufficient reports of PMD determines doctors to be cautious and reserved, approaching these cases more radically than necessary. We reviewed this disease and searched for all cases of PMD associated with healthy, live newborns.

Recurrent GTD and GTD coexisting with normal twin pregnancy

Hydatidiform mole (HM) affects around 1/1000 pregnancies, and in such cases the recurrence risk is around 1%, being greater for those with complete HM (CHM). Whilst most cases appear sporadic with unknown mechanisms, there is a distinct subgroup of patients who suffer recurrent pregnancy loss, including multiple recurrent CHM (familial recurrent biparental HM syndrome). The majority of these cases are related to maternal genetic mutations in genes related to the control of imprinting, specifically NALP7 and KHDC3L. Oocyte donation is an effective treatment allowing these patients to have successful pregnancies. Approximately 1 in 50,000 pregnancies are complicated by twin pregnancy comprising normal foetus and HM, the majority of reported cases being CHM. Such pregnancies are at significantly increased risk of complications, including pregnancy loss, early-onset preeclampsia and severe preterm delivery, but when managed conservatively the delivery of a liveborn healthy infant occurs in around one-third of cases. Regardless of management, the risk of persistent GTD in such cases appears similar to that following singleton CHM. Rarely, other conditions mimic prenatal ultrasound appearances of twin pregnancy with HM, CHM mosaicism and placental mesenchymal dysplasia, both of which have distinctive histological and genetic features.

[Placental mesenchymal dysplasia]

OBJECTIVE

To carry out a clinical and morphological analysis of 6 cases of placental mesenchymal dysplasia (PMD) that is not associated with Beckwith-Wiedemann syndrome.

MATERIAL AND METHODS

Medical records, placental macroscopic and microscopic changes, histochemical (MSB staining) and immunohistochemical studies of placental tissue with antibodies against p57, CD34, smooth muscle actin, desmin, and Ki-67 were analyzed.

RESULTS

Vascular anomalies in the chorionic plate and stem villi, the increased size and edema of the stem villi during normal formation of the terminal branches of the villous tree, the lack of proliferation of villous trophoblast were the typical signs of PMD and were noted in all cases. Comparison of the results of ultrasonography with the morphological pattern of the disease suggested that there were ultrasound signs that were typical of PMD. The characteristics of the course and outcomes of pregnancy in PMD were given. The features of morphological changes in the presence of PMD concurrent with preeclampsia were found. Significant variability in p57 expression in PMD was shown and variants of changes given. There were no substantial features of the expression of desmin and smooth muscle actin in PMD.

CONCLUSION

MDP has typical morphological and ultrasound signs. The significant variability in the levels of chorionic gonadotropin and alpha-fetoprotein and in the expression of p57 does not allow their use in the differential diagnosis of PMD. The high incidence of thrombotic events in the intervillous space and fetal vessels, as well as intrauterine growth restriction, intrauterine hypoxia, and an impaired neonatal adaptation period in PMD should be taken into account when determining the management tactics for female patients and newborns.