Meconium Peritonitis Presenting as a Solitary Calcified Mass on Ultrasound at Mid-trimester and Identified with Fetal Magnetic Resonance Imaging

Meconium peritonitis usually results from perforation of the intestine occurring in utero or shortly after birth. The common features of meconium peritonitis on prenatal ultrasonography are a solitary calcified mass or disseminated intraperitoneal calcifications, ascites, pseudocyst, and occasionally polyhydramnios and fetal hydrops. We report a case where prenatal ultrasound revealed a calcified mass in the right upper quadrant of the abdomen. Subsequent magnetic resonance imaging (MRI) suggested simple meconium peritonitis. Fetal MRI is considered to be reliable for demonstrating meconium peritonitis. Prenatal diagnosis of meconium peritonitis and identification of associated malformations facilitate planning of delivery, earlier surgical counseling, and better neonatal outcome.