Abstract:
Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic twinning whereby a donor twin perfuses an acardiac twin via aberrant vascular anastomoses. The resulting paradoxical retrograde blood flow supplying the acardiac twin is oxygen-poor, leading to some of the most severe malformations encountered in humans. Though the first descriptions of acardiac twins date back to at least the 16th century, the pathophysiologic processes which underpin the development of TRAP sequence are still being elucidated. Theories on the pathogenesis of TRAP sequence include deficiencies intrinsic to the embryo and primary abnormalities of the placental vasculature. Autopsy studies continue to provide clues to the underlying pathogenesis of TRAP sequence, and the characterization of the spectrum of manifestations that can be observed in acardiac twins. Herein, we present the clinical, autopsy, and molecular findings in a unique case of TRAP sequence. Novel findings include a primitive cloaca-like structure and chromosomal aberrations involving 6q11.1 and 15q25.1.
摘要:
双胞胎反向动脉灌注(TRAP)序列是单绒毛膜双胞胎的罕见并发症,供体双胞胎通过异常的血管吻合对无心双胞胎进行灌注。由此产生的矛盾的逆行血流供应无心双胞胎是缺氧的,导致人类遇到的一些最严重的畸形。尽管对无心双胞胎的最早描述可以追溯到至少16世纪,支持TRAP序列发育的病理生理过程仍在阐明中。关于TRAP序列发病机理的理论包括胚胎固有的缺陷和胎盘脉管系统的原发性异常。尸检研究继续为TRAP序列的潜在发病机制提供线索,以及可以在无心双胞胎中观察到的表现谱的特征。在这里,我们提出了临床,尸检,以及在一个独特的TRAP序列病例中的分子发现。新发现包括原始的泄殖腔样结构和涉及6q11.1和15q25.1的染色体畸变。