Meconium ileus is an ailment where an infant’s first feces, termed meconium, prevents the infant’s small intestine’s final segment (ileum). This condition may occur if the meconium is more viscous and sticky than usual.
As the baby ingests everything, the small intestine above the obstruction expands. Small intestine loops may move out (distend) the baby’s belly (abdomen). The large intestine (colon) is smaller than average under the obstruction. It could even be unoccupied or filled with tiny pieces of dried meconium or mucus plugs from the intestine lining.
Doctors generally presume meconium ileus based on symptoms found within a few hours or days after birth.