Meconium peritonitis is a condition where perforation of the bowel due to a number of congenital pathologies, leads to the introduction of meconium into the peritoneal cavity. This causes a sterile inflammatory reaction.
Meconium peritonitis (MP) is a rare condition that results from the development of bowel obstruction in a growing fetus within the uterus. This may lead to perforation of the gut wall, which in turn leads to a leakage of meconium into the peritoneal cavity. Aseptic peritonitis ensues, due to a secondary inflammatory response. The outcome of MP depends to some extent on diagnostic and management approaches, which have greatly improved over the years  . Severity and symptomatology of the condition are determined by the gestational age of the fetus, at the time the perforation occurs.
There are many possible causes of bowel obstruction in utero. These range from vascular factors such as mesenteric ischemia, to bowel pathologies such as meconium ileus, intussusception, volvulus, intestinal atresia, Hirschsprung's disease, hernias, and meconium plugs . In addition to these, congenital infections, particularly parvovirus B19, rubella and cytomegalovirus, have been shown to be predisposing factors in the occurrence of MP . There is an established association between MP and cystic fibrosis . Polyhydramnios, jejunoileal atresia, and other gastrointestinal malformations have also been linked to MP.
There are three main classes of MP, the first being fibro-adhesive. This results in calcification and tissue deposition on the area of perforation, producing a mass that seals the defect. Most perforations are closed off before birth. The other types of MP are cystic and generalized. Additional effects of the inflammatory changes that may occur include ascites, fibrosis and intraperitoneal meconium calcifications.
The diagnosis of meconium peritonitis can be made either in utero or after birth. Some features of the disease can spontaneously resolve before birth. It may be beneficial to test for cystic fibrosis, as there is a strong correlation between the two conditions.
During the prenatal period, imaging techniques are used to assess the fetal abdomen. These are: