This document discusses meconium disease, specifically meconium ileus. Meconium ileus is a common cause of intestinal obstruction in newborns, accounting for 9-33% of cases. It is characterized by thick, viscous meconium that obstructs the distal ileum. Meconium ileus is often an early manifestation of cystic fibrosis. The document describes the clinical presentation of meconium ileus and methods of prenatal diagnosis using ultrasound. Complications can include volvulus, gangrene, atresia and perforation.