Placental chorioangioma presenting prenatal hemolytic anemia and consumption coagulopathy: a case report

Introduction

Placental chorioangioma is a histologically benign tumor corresponding to either hematomas derived from primitive chorionic mesenchyma or placental hemangiomas arising from placental blood vessels [1]. Although it is considered a common benign lesion, large and/or multiple chorioangiomas can cause serious fetal impairments such as anemia, polyhydramnios, hyperdynamic heart strain, non-immune hydrops, and fetal growth restriction [2]. A newborn with a large chorioangioma was reported to require intensive care immediately after birth for coagulopathy, including hemolytic anemia and thrombocytopenia caused prenatally by the chorioangioma [3]. Here, we report a case involving a large chorioangioma leading to fetal hemolytic anemia and consumption coagulopathy diagnosed by fetal blood sampling (FBS).

Case report

A 25-year-old woman, primigravida, was referred to our hospital at 29 weeks of gestation for a placental tumor detected on routine ultrasound examination at 28 weeks of gestation. A detailed ultrasound examination using a Voluson E8 scanner (GE Healthcare, Milwaukee, WI, USA) revealed a large mass (90×80 mm in area) arising from the chorionic plate on the placenta (Figure 1). The mass was located near the cord insertion site. Power Doppler imaging revealed that the mass was highly vascularized (Figure 2), and numerous vessels were connected to the umbilical cord. Placental chorioangioma was diagnosed prenatally based on these ultrasound findings. The fetus had no structural abnormalities. Fetal echocardiography did not indicate cardiomegaly, and Doppler imaging did not demonstrate abnormal findings. Fetal growth was normal for gestational age with no polyhydramnios up to 32 weeks of gestation.

Figure 1:

Ultrasound imaging at 29 weeks of gestation.

B-mode ultrasound reveals a large mass arising from the chorionic plate.

Figure 2:

Ultrasound imaging at 29 weeks of gestation.

Power Doppler ultrasound reveals blood supply to the mass.

At 34+1 gestation, polyhydramnios was observed (amniotic fluid index 280). The size and echogenicity of the mass did not appear changed after polyhydramnios developed. Fetal echocardiography demonstrated cardiomegaly (cardiothoracic area ratio, 40%) and mild tricuspid regurgitation. The peak systolic velocity (PSV) of the descending aorta was 176.0 cm/s (normal range for 34-week gestational age, 67.6–141.5 cm/s) [4], and the middle cerebral artery-PSV was 78 cm/s, corresponding to a 1.55-fold increase over the median expected value [5]. These findings suggested fetal anemia and hyperdynamic circulation. The fetal heart rate pattern was reassuring.

At 34+4 gestation, cordocentesis was performed to assess the degree of expected anemia. The same sample was used for blood coagulation testing to evaluate coagulopathy. Analysis revealed a hemoglobin concentration of 9.3 g/dL, hematocrit of 29%, platelet count of 62,000/μL, prothrombin time (PT) of 18.6 s, prothrombin time-international normalized ratio (PT-INR) of 1.63, and activated partial thromboplastin time (APTT) of 75.1 s. Blood smear indicated a fragmented red cell count of 63/1000. Thus, FBS demonstrated microangiopathic hemolytic anemia and the presence of consumption coagulopathy.

A cesarean section was performed at 34+4 gestation to avoid worsening of microangiopathic hemolytic anemia and consumption coagulopathy. A female newborn weighing 2158 g was born, with Apgar scores of 6 and 8 at 1 and 5 min, respectively. The umbilical artery pH was 7.295. Her skin was slightly edematous, with petechial hemorrhage at the abdomen and leg. Neonatal blood sampling revealed a white blood cell count of 7890/μL, hemoglobin concentration of 9.1 g/dL, hematocrit of 27%, platelet count of 62,000/μL, reticulocyte count of 64‰, PT of 16.7 s, PT-INR of 1.45, APTT of 66.1 s, similar to the results of FBS. In addition, fibrinogen not exceeding 50 mg/dL and a D-dimer level of 13.1 μg/mL confirmed the diagnosis of consumption coagulopathy. Biochemical examination revealed alanine transaminase of 40 IU/L, aspartate aminotransferase of 5 IU/L, lactate dehydrogenase of 661 IU/L, total bilirubin of 2.5 mg/dL, and C-reactive protein of 0.02 mg/dL. There were no findings suggestive of liver dysfunction or infection. Chest radiography revealed a cardiothoracic ratio of 68% and pulmonary congestion. Echocardiography demonstrated mitral regurgitation and fractional shortening of 28%. These findings indicated hyperdynamic cardiac function.

The infant was administered catecholamine for hyperdynamic cardiac function and fresh frozen plasma for consumption coagulopathy in the neonatal intensive care unit. Her general condition improved, and she was discharged in good health at 19 days of age. On gross examination, the fetal side of the placenta demonstrated a large mass up to 90×80 mm in area (Figure 3). Histological examination confirmed a placental chorioangioma (Figure 4).

Figure 3:

Gross anatomy of the placenta.

A chorioangioma on the fetal side of the placenta demonstrates a large mass (90×80 mm in area). Superficial feeding vessels connected to the umbilical cord.

Figure 4:

Histological presentation of placental chorioangioma.

A placental tumor shows proliferation of spindle-shaped tumor cells forming many small lumens (hematoxylin and eosin stain, ×100).

Discussion

Several reports have described anemia, thrombocytopenia, and coagulopathy complicating placental chorioangioma during the perinatal period [4]. The pathological mechanisms of fetal anemia are a consequence of either fetomaternal hemorrhage, microangiopathic hemolysis occurring in the winding chorioangioma blood vessels, and/or blood sequestration in the intravascular space of the tumor [2]. Thrombocytopenia and coagulopathy are thought to arise from injured erythrocytes and trapped platelets circulating through tortuous and partially thrombosed vascular networks [6]. Consumption of blood cells in the tumor causes hemolytic anemia, thrombocytopenia, and coagulopathy. Cases of blood transfusion for fetal anemia and thrombocytopenia diagnosed with FBS via cordocentesis have been reported [2], and another reported case involved neonatal coagulopathy caused by a large placental chorioangioma [3]. However, no previous cases have involved the identification of fetal coagulopathy in utero. In our case, FBS revealed the presence of fragmented red cells, and thrombocytopenia indicated consumption coagulopathy. This report is the first to identify a condition similar to Kasabach-Merritt phenomenon already present in the fetal period using FBS.

Several fetal therapies for complications associated with placental chorioangioma have been reported, for example, intrauterine fetal transfusion, fetoscopic laser coagulation, alcohol injection [7]. We did not consider any fetal therapy because fetal maturation was expected at the time. The first-line therapy for Kasabach-Merritt phenomenon is surgical excision of the tumor [8]. Therefore, we selected termination of pregnancy, aiming to excise the tumor from the fetus.

We report the diagnosis of consumption coagulopathy in a fetus using FBS. When fetal anemia is suspected in a case of large placental chorioangioma, the possibility of developing coagulopathy during the fetal period should be considered. Precise information from the fetal blood that can be extrapolated to the newborn infant is useful for neonatal treatment. It is unclear whether fetal coagulopathy in the prenatal period worsens acutely or chronically during pregnancy complicated by placental chorioangioma. Although the delivery was performed immediately after we diagnosed consumption coagulopathy, it remains unknown whether termination should be considered when the coagulopathy is observed during the earlier preterm period.