Sirenomelia (Q46709): Difference between revisions

Sirenomelia is a rare lethal malformation characterised by severe anomalies of the caudal part of the fetus that include a single lower limb, with various degrees of involvement ranging from single to separate femurs in the same skin shaft, presence of two feet (sympode mermaid) or one foot (monopode mermaid), to absence of both feet (ectromelic mermaid). Urogenital anomalies are also present and include bilateral renal agenesis, absence of outflow tract and absence of external genitalia. Imperforate anus and sacro-coccygeal agenesis have also been reported. Together these malformations comprise the extreme form of the caudal regression sequence.