**1. Introduction**

Meconium ileus is a type of neonatal intestinal obstruction that occurs when abnormally thick and tenacious meconium becomes impacted, thus creating a blockage in a part of the distal small intestine, usually the ileum [1, 2]. It accounts for about 30–33% of cases of neonatal small intestinal obstruction [3]. Meconium ileus is a rare condition affecting only 1 in 25,000 babies [4]. It occurs in either a simple or a complicated form and is said to be the earliest clinical manifestation of cystic fibrosis occurring in approximately 16–20% of patients with cystic fibrosis [4]. Cystic fibrosis is a disease condition characterized by abnormally thick intestinal secretions and pancreatic insufficiency.

While majority of patients with meconium ileus have the disease cystic fibrosis (80–90%), a few of them do not have it; approximately 20% of one series of cases of meconium ileus did not have cystic fibrosis [5]. Preterm infants whose mothers had medications to slow down labor are sometimes associated with meconium ileus.

Meconium is the first series of stools that a newborn pass. It is formed during intrauterine life and consists of shed intestinal epithelial cells, bile, succus entericus, mucus, lanugo, and amniotic fluid ingested in utero. It is a dark olive green viscous and almost odorless substance that comprises the initial stools of the newborn. Meconium contains lactic acid-producing bacteria (e.g., *Lactobacillus*) and the so-called enteric bacteria family (e.g., *Escherichia coli*) [6]. It is usually evacuated within the first 24–48 hours after birth following which the usual yellowish feces are passed by the neonate. However, there might be in utero evacuation of meconium as a result of a vagal response due to perinatal stress to the fetus. Such newborn immediately after delivery may develop signs of respiratory distress from meconium aspiration syndrome.

Meconium ileus may be associated with complications such as meconium peritonitis, ileal atresia or stenosis, ileal perforation, and volvulus with or without pseudocyst formation [7–13]. The infants with cystic fibrosis are more likely to present with complicated meconium ileus [14].
