Yasuda Y, Mitomori T, Matsuura A, Tanimura T
Teratology. 1985 Jun;31(3):337-44. doi: 10.1002/tera.1420310304.
A 5 month-old female was brought to our clinic because of diarrhea and abdominal distension. A plain radiograph demonstrated a mass with a vertebral column in the right upper quadrant of the abdomen. At operation a mass was found to be retroperitoneal, well encapsulated, and connected to the abdominal aorta of the host by two small vessels; no other connections and adhesions were seen between the mass and the host. The ovaries, uterus, and other pelvic and abdominal viscera of the host were normal. The mass was diagnosed as a fetus-in-fetu. The fetus-in-fetu, encapsulated with an amniotic capsule, was covered with skin and had a top with long hair, two protuberances, an amniotic hernial sac, upper limbs with syndactylic fingers, a gluteal region, and lower limbs with polysyndactylic toes. A brain mass and a spinal cord were identified in the cranial cavity and the vertebral canal. Several spinal ganglia and a nerve plexus were found. A noselike structure, upper lip, maxillalike bone with teeth, tonguelike structure, intestines, ribs, bones of the extremities, and skeletal muscles were also identified. A cloacalike cyst was observed to have an opening in the external female genitalia. Microscopically, a small number of motor neurons were seen in the brain mass and the anterior horn of the spinal cord. In the spinal ganglia, ganglion cells were differentiated. The submucosal and myenteric plexuses were seen in the intestinal wall. Well-differentiated muscle fibers were often accompanied with myelinated nerve fibers. Hematopoiesis was observed in the cranial bone marrow. The presence of the sex chromatin was confirmed in the nuclei of motor neurons and polymorphonuclear leukocytes. Thus, the present fetus-in-fetu, which was connected to the abdominal aorta of the host by two vessels, was a monozygotic twin which developed within its own amniotic cavity.
一名5个月大的女婴因腹泻和腹胀被带到我们诊所。腹部平片显示腹部右上象限有一个与脊柱相连的肿块。手术中发现肿块位于腹膜后，包膜完整，通过两条小血管与宿主的腹主动脉相连；肿块与宿主之间未见其他连接和粘连。宿主的卵巢、子宫以及其他盆腔和腹部脏器均正常。该肿块被诊断为胎内胎。胎内胎被羊膜囊包裹，表面覆盖皮肤，顶部有长发，有两个突起、一个羊膜疝囊、上肢有并指、臀部区域以及下肢有多趾。在颅腔和椎管内发现了脑肿块和脊髓。还发现了几个脊神经节和一个神经丛。还识别出了鼻样结构、上唇、有牙齿的上颌样骨、舌样结构、肠、肋骨、四肢骨骼和骨骼肌。观察到一个泄殖腔样囊肿在女性外生殖器处有开口。显微镜下，在脑肿块和脊髓前角可见少量运动神经元。在脊神经节中，神经节细胞已分化。肠壁可见黏膜下神经丛和肌间神经丛。分化良好的肌纤维常伴有有髓神经纤维。在颅骨骨髓中观察到造血现象。在运动神经元和多形核白细胞的细胞核中证实了性染色质的存在。因此，本病例中通过两条血管与宿主腹主动脉相连的胎内胎是在其自身羊膜腔内发育的单卵双胎。
