Left Isomerism (Polysplenia Syndrome)

Left isomerism (IS), also known as polysplenic syndrome, is part of the category of heterotaxic syndromes. Heterotaxic syndrome is a general term that describes the abnormal positioning of the viscera in the chest and abdomen. Signs of polysplenic syndrome include: bilobed lungs, liver located on the median line, but also intestinal malrotation. The prevalence of this condition is 1.4 patients per 10,000 children. The clinical aspect is closely correlated with the specific pathology of polysplenism. Apparently, incidental signs and symptoms are encountered, unexplained and unassociated from the etiopathogenic point of view, until the imaging examination that elucidates the causes of the observed clinical picture. As such, polysplenism, i.e., left isomerism, is the result of the abnormal development of the asymmetry of the laterality of the organs having the effect of situs ambiguus.