Spontaneous twin anemia–polycythemia sequence complicated by recipient placental vascular thrombosis and hydrops fetalis

Abstract

Twin anemia–polycythemia sequence (TAPS) is an atypical form of twin–twin transfusion syndrome (TTTS) that presents as a large intertwin hemoglobin difference with one twin developing anemia and the other developing polycythemia, without oligohydramnios–polyhydramnios sequence (Lopriore et al., Placenta 2007;28:47–51). The prenatal diagnostic criteria for TAPS require that the middle cerebral artery-peak systolic velocity (MCA-PSV) measure greater than 1.5 multiples of median (MoM) in the donor twin and less than 0.8 MoM in the recipient twin (Robyr et al., Am J Obstet Gynecol 2006;194:796–803; Klaritsch et al., Ultrasound Obstet Gynecol 2009;34:149–154; Mari et al., N Engl Med 2000;342:9–14). The presumed etiology of TAPS involves the presence of small caliber arteriovenous anastomoses, which generate a slow transfusional process allowing for hemodynamic compensation (Lopriore et al., Placenta 2007;28:47–51; Lopriore et al., Placenta 2009;30:223–225; Lewi et al., Am J Obstet Gynecol 2006;194:790–795; Lopriore et al., Am J Obstet Gynecol 2008;112:753–758; Van den Wijngaard et al., Placenta 2007;28:611–615). The resulting polycythemia in the recipient twin is a risk factor for fetal and placental thrombosis (Van den Wijngaard et al., Am J Physiol 2005;288:R799–R814). We present a case of spontaneous TAPS complicated by a large placental vessel thrombosis and hydrops fetalis. Treatment via selective laser photocoagulation of communicating vessels (SLPCV) resulted in normalization of the MCA-PSV discordance.

Keywords:

• Placental thrombosis
• hydrops fetalis
• twin anemia–polycythemia sequence
• twin–twin transfusion syndrome
• selective laser photocoagulation of communicating vessels

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.