Portal de Periódicos da CAPES

Placental mesenchymal dysplasia

2011; Elsevier BV; Volume: 205; Issue: 6 Linguagem: Inglês

10.1016/j.ajog.2011.08.019

1097-6868

Gregory W. Woo, Frederico G. Rocha, Maria Gaspar-Oishi, Marguerite Lisa Bartholomew, Karen Thompson,

Prenatal Screening and Diagnostics

Placental mesenchymal dysplasia is a benign condition that can be confused with a molar pregnancy by ultrasound scanning and gross examination. Conservative management should be considered with a normal-appearing singleton fetus and a cystic-appearing placenta. We present a case of placental mesenchymal dysplasia with a favorable outcome. Placental mesenchymal dysplasia is a benign condition that can be confused with a molar pregnancy by ultrasound scanning and gross examination. Conservative management should be considered with a normal-appearing singleton fetus and a cystic-appearing placenta. We present a case of placental mesenchymal dysplasia with a favorable outcome. Placental mesenchymal dysplasia (PMD) is a rare benign condition that is characterized by placentomegaly and grapelike vesicles that can resemble a molar pregnancy by ultrasound and gross placental examination.1Parveen Z. Tongson-Ignacio J.E. Frasier C.R. Killeen J.L. Thompson K.S. Placental mesenchymal dysplasia.Arch Pathol Lab Med. 2007; 131: 131-137PubMed Google Scholar PMD was described initially by Moscoso et al2Moscoso G. Jauniaux E. Huston J. Placental vascular anomaly with diffuse mesenchymal stem villous hyperplasia: new clinico-pathological entity?.Pathol Res Pract. 1991; 187: 324-328Crossref PubMed Scopus (107) Google Scholar as stem villous hyperplasia with elevated maternal serum alpha-feto-protein and enlarged placentas with ultrasound features that are suggestive of partial mole. PMD should be included in the differential for a cystic-appearing placenta with a normal fetus.3Matsui H. Iitsuka Y. Yamazawa K. et al.Placental mesenchymal dysplasia initially diagnosed as partial mole.Pathol Int. 2003; 53: 810-813Crossref PubMed Scopus (48) Google Scholar Herein, we describe a case of PMD with emphasis on sonographic findings and pathologic correlation. A 21-year-old woman (3 pregnancies; 0111 [para: 0 term delivery, 1 preterm delivery, 1 abortion, 1 living] viable births) with a normal-appearing fetus and an abnormal-appearing cystic placenta on ultrasound scanning was transferred at 19 weeks to the Maternal Fetal Medicine clinic. The patient had a normal sequential screening, except for an elevated alpha-feto-protein (multiples of the median, 5.4; human chorionic gonadotropin [HCG] multiples of the median, 6.95), a normal fetal karyotype (46 mIU/mL), and an elevated β-HCG level of 167402. A chest x-ray, liver enzyme levels, and renal laboratory values were normal. The thyrotropin level indicated hyperthyroidism, which was treated with propothiouracil. The differential diagnosis included a complete molar pregnancy with co-twin, a partial molar pregnancy, a chorioangioma, or PMD. The patient elected to continue the pregnancy and accepted the increased risk of preeclampsia (27%),4Wee L. Jauniaux E. Prenatal diagnosis and management of twin pregnancies complicated by a co-existing molar pregnancy.Prenat Diagn. 2005; 25: 772-776Crossref PubMed Scopus (69) Google Scholar persistent gestational trophoblastic disease (GTD; 45%),5Paradinas F.J. Sebire N.J. Fisher R.A. et al.Pseudo-partial moles: placental stem vessel hydrops and the association with Beckwith-Wiedemann syndrome and complete moles.Histopathology. 2001; 39: 447-454Crossref PubMed Scopus (94) Google Scholar fetal loss (62%),4Wee L. Jauniaux E. Prenatal diagnosis and management of twin pregnancies complicated by a co-existing molar pregnancy.Prenat Diagn. 2005; 25: 772-776Crossref PubMed Scopus (69) Google Scholar and maternal morbidity.4Wee L. Jauniaux E. Prenatal diagnosis and management of twin pregnancies complicated by a co-existing molar pregnancy.Prenat Diagn. 2005; 25: 772-776Crossref PubMed Scopus (69) Google Scholar At 24, 28, and 32 weeks' gestation (Figure 1) , the placenta continued to be large and hydropic by ultrasound scanning. Throughout the pregnancy, the fetal growth curves were normal. Gestational hypertension was diagnosed with a normal 24-hour urine test (150 mg) with elevated blood pressures 6 hours apart along with normal laboratory values at 32 weeks' gestation. The patient then returned at 33 weeks' gestation in preterm labor (9 cm) and within 1 hour delivered a viable female infant (1802 g; 40%), with Apgar scores of 4 and 7. The placenta appeared grossly large with hydropic villi (Figure 2) . Evaluation of the infant by the neonatal team was normal. The patient recovered normally and was discharged home on postpartum day 2. The B-HCG decreased 2 weeks after the delivery to 113 mIU/mL, but the patient was then lost to follow-up evaluation. Grossly, the placenta was markedly enlarged (1380 g). The fetal surface had multiple dilated chorionic plate vessels with areas of aneurysmal dilation. The cut surface revealed numerous cystically dilated vesicles that were interspersed between normal-appearing parenchyma with a chorioangioma (3.0 cm). Microscopic sections showed markedly enlarged villi with dilated central cisterns, thick-walled fibromuscular vessels, loose myxoid stroma, and chorangioma vasculature (Figure 2). The trophoblast was nonproliferative. P57 stain showed decreased, but not absent, staining in cytotrophoblast and villous stromal nuclei, and fluorescence in situ for hybridization for X and Y that was performed in 2 morphologically different areas of the placenta revealed diploidy. PMD is a rare benign condition that should be considered in the differential diagnosis when ultrasound findings demonstrate a placenta with cystic changes and a normal fetus. The exact incidence of PMD is unknown because of its rarity with a 3.6:1 female:male preponderance. The fetus with PMD can develop normally without severe maternal complications. It is important to distinguish PMD from a partial mole with an abnormal triploid fetus, because this diagnosis may result in pregnancy termination. It is challenging to distinguish PMD from a complete mole with co-twin, which carries significant morbidity to the mother (persistent GTD). It appears that suppressed thyrotropin and pregnancy-related hypertension also occurs in PMD. PMD is associated with Beckwith-Wiedemann syndrome (macrosomia, exomphalos, macroglossia, omphalocele, craniofacial features, and ear anomalies) in 25% of cases. The patient should be counseled on the potential associations of Beckwith-Wiedemann syndrome with prematurity, fetal growth restriction, or intrauterine fetal death.3Matsui H. Iitsuka Y. Yamazawa K. et al.Placental mesenchymal dysplasia initially diagnosed as partial mole.Pathol Int. 2003; 53: 810-813Crossref PubMed Scopus (48) Google Scholar Additionally, the degree of vascularity and shunting in the placenta may lead to complications to fetus (fetal growth restriction or intrauterine fetal death) and to the mother (hypertension).1Parveen Z. Tongson-Ignacio J.E. Frasier C.R. Killeen J.L. Thompson K.S. Placental mesenchymal dysplasia.Arch Pathol Lab Med. 2007; 131: 131-137PubMed Google Scholar Sonographic findings of PMD demonstrate a thickened placenta with hypoechoic areas (Figure 1) that can resemble a complete mole with co-twin, a partial molar pregnancy, or a chorioangioma (Table). The placenta of a complete mole with co-twin and partial molar pregnancy look heterogeneous, with partially solid and cystic areas. A chorioangioma has different echogenicity sonographically than the rest of the placenta and is located on the fetal placental surface.6Vaiabuch E. Romero R. Kusanovic J.P. et al.Three dimensional sonography of placental mesenchymal dysplasia and its differential diagnosis.J Ultrasound Med. 2009; 28: 359-368PubMed Google Scholar, 7Cohen M.C. Roper E.C. Sebire N.J. Stanek J. Anumba D.O. Placental mesenchymal dysplasia associated with fetal aneuploidy.Prenat Diagn. 2005; 25: 187-192Crossref PubMed Scopus (82) Google ScholarTABLEUltrasound and pathologic differentiationsVariablePlacental mesenchymal dysplasiaComplete molar pregnancy with co-twinPartial molar pregnancyNormal pregnancy with chorioangiomaUltrasound scan of the placentaPlacenta with hypoechoic/multicystic areas: may see normal area of placenta; may be thickenedPlacenta in 1 sac with hypoechoic/multicystic areas: may or may not see separating membrane; may be thickened; placenta in second sac with fetus appears normalPlacenta with hypoechoic/multicystic areas: thickenedLocated on the fetal placental surface with different echogenicity than the rest of the placenta; contains copious Doppler flow in massUltrasound scan of the fetusMay appear normalMay appear normal with a second normal-appearing placentaUsually abnormal-appearing fetusMay appear normalGross pathologic condition of the placentaLarge for gestational age with cystically dilated vesiclesLarge for gestational age with cystically dilated vesicles and normal-appearing placentaLarge for gestational age with cystically dilated vesiclesUsually normal placenta with smooth round mass on fetal surface of the placentaMicroscopic characteristics of placentaDilated stem vessels and lack of trophoblastic proliferationDilated stem vessels with trophoblastic proliferationLess prominent dilated stem vessels than a complete molar pregnancy with trophoblastic proliferationDilated small vessels and capillaries lined with a single layer of endothelial cells with normal placentaWoo. Placental mesenchymal dysplasia. Am J Obstet Gynecol 2011. Open table in a new tab Woo. Placental mesenchymal dysplasia. Am J Obstet Gynecol 2011. Grossly, PMD placentas are large for gestational age with aneurysmally dilated chorionic plate vessels with fibromuscular hyperplasia. Cystically dilated vesicles are present, which are similar to those seen in molar pregnancies. Microscopically, these vesicles correspond to dilated stem vessels with thickened vasulature surrounded by normal villi. Pathologically, PMD can be distinguished by the presence of dilated stem vessels and lack of trophoblastic proliferation.1Parveen Z. Tongson-Ignacio J.E. Frasier C.R. Killeen J.L. Thompson K.S. Placental mesenchymal dysplasia.Arch Pathol Lab Med. 2007; 131: 131-137PubMed Google Scholar In conclusion, PMD should be included in the differential diagnosis for ultrasound findings that show a normal-appearing fetus with cystic lesions of the placenta.1Parveen Z. Tongson-Ignacio J.E. Frasier C.R. Killeen J.L. Thompson K.S. Placental mesenchymal dysplasia.Arch Pathol Lab Med. 2007; 131: 131-137PubMed Google Scholar There should be a careful assessment that should include fetal karyotype and studies to evaluate for the possibility of GTD. Patients should be counseled about the increased risk of preeclampsia,4Wee L. Jauniaux E. Prenatal diagnosis and management of twin pregnancies complicated by a co-existing molar pregnancy.Prenat Diagn. 2005; 25: 772-776Crossref PubMed Scopus (69) Google Scholar persistent (GTD),5Paradinas F.J. Sebire N.J. Fisher R.A. et al.Pseudo-partial moles: placental stem vessel hydrops and the association with Beckwith-Wiedemann syndrome and complete moles.Histopathology. 2001; 39: 447-454Crossref PubMed Scopus (94) Google Scholar fetal loss,4Wee L. Jauniaux E. Prenatal diagnosis and management of twin pregnancies complicated by a co-existing molar pregnancy.Prenat Diagn. 2005; 25: 772-776Crossref PubMed Scopus (69) Google Scholar maternal morbidity,4Wee L. Jauniaux E. Prenatal diagnosis and management of twin pregnancies complicated by a co-existing molar pregnancy.Prenat Diagn. 2005; 25: 772-776Crossref PubMed Scopus (69) Google Scholar and Beckwith-Wiedemann syndrome.3Matsui H. Iitsuka Y. Yamazawa K. et al.Placental mesenchymal dysplasia initially diagnosed as partial mole.Pathol Int. 2003; 53: 810-813Crossref PubMed Scopus (48) Google Scholar Pediatricians should also be informed about these associations.3Matsui H. Iitsuka Y. Yamazawa K. et al.Placental mesenchymal dysplasia initially diagnosed as partial mole.Pathol Int. 2003; 53: 810-813Crossref PubMed Scopus (48) Google Scholar Close follow-up evaluation is needed because preterm labor and hypertensive disorders of pregnancy are not uncommon. Placental pathologic examination is paramount to make the diagnosis. Finally, more research is needed on the true incidence of complications and types of complications that are associated the PMD.