Mondo Description Czeizel-Losonci syndrome (CLS) is an exceedingly rare, severe, congenital genetic malformation disorder characterized by split hand/split foot, hydronephrosis, and spina bifida. Spinal and skeletal manifestations were thoracolumbar scoliosis, spinabifida (spina bifida occulta or spina bifida cystic), Bochdalek diaphragmatic hernia, and radial defects.There have been no further descriptions in the literature since 1987.