Bean syndrome or blue rubber bleb nevus syndrome (BRBNS) is a rare disorder characterized by venous malformation of varying size and appearance present mainly on the skin and gastrointestinal tract. The diagnosis is usually established in the postnatal period or later when complications occur, including anemia or intestinal bleeding1, 2. We report two prenatal cases of large cutaneous venous malformations that were associated with BRBNS and were complicated by life-threatening consumptive coagulopathy soon after birth.
The first patient was referred at 29 weeks' gestation with an isolated large axillary cystic lesion (48 × 32 mm) detected on routine ultrasound examination. Numerous septa and echogenic nodules were present (Figure 1a and b). The lesion had a heterogeneous intermediate signal on T2-weighted magnetic resonance imaging (MRI) and the echogenic nodules demonstrated hypersignals and hyposignals on T1- and T2-weighted imaging, respectively (Figure 1c). Deformation of the chest wall and the intermediate signal on T2-weighted images were retrospectively atypical of our prenatal diagnosis of macrocystic lymphatic malformation (Figure 1d). Postnatal examination confirmed a huge left axillary mass associated with a 5-mm bleb lesion on the right foot and many punctiform lesions suggestive of BRBNS (Figure 2a–c). Consumptive coagulopathy occurred in the first days of postnatal life and warranted antithrombotic treatment and percutaneous sclerotherapy using Ethibloc and alcohol. Two additional sclerotherapies resulted in a significant decrease in size of the mass (Figure 2d).
The second patient was referred at 25 weeks' gestation with an exophytic midline dorsal tumoral lesion (65 × 45 mm) detected on a routine ultrasound examination. The lesion was mainly cystic with thin internal echoes and septa (Figure 3a). Findings on MRI were similar to those of the previous case (Figure 3b). Postnatal examination confirmed a huge angiomatous dorsal mass of venous origin associated with a blue papule on the scalp suggestive of BRBNS (Figure 3c). MRI confirmed typical findings of a large venous lesion with multiple internal thromboses (Figure 3d and e). Because of severe coagulopathy, percutaneous sclerotherapy using alcohol and Sotradecol was performed at the age of 1 month. This procedure was complicated by cardiac arrest and severe pulmonary hypertension (most likely due to alcohol washout in the venous drainage). A few days later, massive external bleeding warranted complete excision of the mass. The baby recovered well.
The most commonly prenatally diagnosed vascular anomalies of the soft tissue are congenital hemangio- mas3, 4. Venous malformations of the soft tissue and BRBNS are rarely identified prenatally. Venous malformations are low-flow lesions with a cystic appearance characterized by multiple septa with no vascularization detected on color Doppler imaging5, 6. The principal differential diagnosis is macrocystic lymphatic malformation. Internal echoes and internal thrombosis demonstrated on ultrasound imaging and fetal MRI, as well as an intermediate signal on T2-weighted imaging, should suggest a venous malformation rather than a macrocystic lymphatic malformation, the latter typically demonstrating a hypersignal on T2-weighted imaging (Figure 1d)5. Moreover, macrocystic lymphatic malformations do not create a mass effect as the one encountered in our first case (Figure 1c).
In the postnatal period, venous malformations are usually isolated and rarely associated with BRBNS5. Prenatally, the association is more likely when the venous malformation is large. Its management differs from that of an isolated venous malformation owing to the increased risk of consumptive coagulopathy7. Surgery as an initial treatment may worsen the coagulopathy whereas percutaneous sclerotherapy is generally a safe and effective method6, 8, 9. We therefore recommend that perinatal management of vascular lesions that are suspected prenatally should involve close collaboration with specialists in vascular malformations.