EP14.02: Parasitic twin as a human true tail, the pathogenesis of human true tail revealed: the largest human embryo as a parasite – extremely rare case report

Conjoined twins are one of the rare developmental anomalies in which twins share some structures. An asymmetric type parasitic twin (heteropagus) was reported. A twenty-eight-year-old primigravida lady was admitted with the diagnosis of preterm prelabour rupture of membrane at a gestational age of 36 weeks. The parasitic twin was born through spontaneous vertex delivery. Upon examination, the parasitic tissue of 58mm in length and 40gm weight attached to the autosite sacral area 10mm left lateral from the midline through a 110mm long tail-like structure extending from the caudal part of the parasite. The parasite had anatomic structures similar to human embryos at about 5 weeks. Further work-up to the autosite showed no associated gross congenital anomaly. The distal component of the parasite looks like a developmentally arrested human embryo at 5-6 weeks and grows due to continuous blood supply from the autosite. The parasitic twins were separated by minor surgical excision for cosmetic and cultural reasons. The autosite was in good health at postpartum visits. An extremely rare coincidence of parasitic twins as human true tail is reported. It gives evidence to the controversial pathogenesis of the human true tail. Some case reports about the human tail can be ruminants of the twin process that has arrested at early embryonic age and lost its distal component by ischemic resorption rather than the true human tail. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.