Introduction

Meconium ileus (MI) is congenital obstruction of the distal small bowel due to inspissated meconium within the ileum and sometimes the colon. It is most often a neonatal manifestation of cystic fibrosis (CF) and occurs in ten to twenty percent of newborns with that disorder [1]. MI is the only significant clinical manifestation of CF that is evident at birth.

Meconium ileus is classified as simple or complicated and the incidence of each type in neonates is evenly divided [2]. The distinction is critical to the management. Simple MI means that the intestinal obstruction is due exclusively to intraluminal occlusion from viscid meconium within an intact intestinal tract. Complicated MI is exacerbated by atresia, volvulus and/or perforation sometimes with pseudocyst formation.

Meconium ileus can cause small bowel volvulus from kinking when the fetal intestine is made heavy by thick tenacious meconium. Volvulus can result in perforation and atresia. When perforation occurs in utero the condition is called meconium peritonitis. Meconium peritonitis raises suspicion of CF and complicated MI, although most studies suggest that a minority of fetuses with in utero diagnosis of meconium peritonitis will have CF [3].

see also Meconium Ileus Procedures

Content in this topic is referenced in SCORE Meconium Ileus/Peritonitis/Plug overview