Meconium ileus
Obstruction of the intestine (ileus) due to overly thick meconium, the dark sticky stuff that is normally present in the intestine at birth and, after trypsin and other enzymes from the pancreas have acted on it, is normally passed in the feces after birth.
Meconium ileus results from a deficiency of trypsin and other digestive enzymes from the pancreas, as in cystic fibrosis (fibrocystic disease of the pancreas, mucoviscidosis).