*Ultrasound Division, ASL Roma B, Rome, Italy; firstname.lastname@example.org
**Department of Pediatrics, Policlinico Umberto I, Università “La Sapienza” Rome, Italy;
***Ultrasound Division, Ceprano Hospital, Ceprano, Italy.
Meconium is the content of fetal gastro-intestinal tract. If the meconium spills out through a bowel perforation into the peritoneal cavity, it is irritative and elicits an inflammatory response referred to as meconium peritonitis.
Perforation and leakage of the meconium usually occurs just proximal to an area of bowel obstruction. For example, meconium peritonitis can occur proximal to an atretic segment of small bowel or proximal to a meconium plug in a fetus with cystic fibrosis. In some cases the cause of meconium leakage cannot be determined.
Fetal response to the chemical peritonitis produces a number of intraperitoneal findings occurring after the intraperitoneal meconium leakages. There may be an abnormal fluid collection in the peritoneal cavity, either free (ascites) or bounded within a meconium cyst. The fluid meconium content calcifies, and subsequently, intraperitoneal calcifications may develop, either on the serosal surface of the bowel or liver or in the wall of a meconium cyst. If the processus vaginalis is patent at the time of perforation, calcification may also be seen in the scrotum.
This is a case of a 26-year-old patient (G2P1) that was seen at 20 weeks of her gestation with non-contributive personal or family history. First ultrasound examination was performed elsewhere at 13 weeks and was reported to be normal.
Our examination found scattered hyperechoic spots on the peritoneum of the liver and spleen surface and adjacent anterior abdominal wall. The gallbladder appeared small. Amniotic fluid volume was at the upper limit for the gestational age (AFI 20 cm). There was no evidence of fetal ascites or dilated bowel loops or other anomalies. Placental thickness was within normal limits for gestational age. A few hyperechoic spots were also seen within the right scrotum suggesting a meconium periorchitis. The findings led us to the diagnosis of simple meconium peritonitis.
Maternal serology for toxoplasmosis, cytomegalovirus and parvovirus B19 was negative. Amniocentesis for aneuploidies and cystic fibrosis investigation was suggested but parents declined these tests.
The patient was scanned again at 31 weeks. Amniotic fluid volume was at the upper limit (AFI 19 cm), fetal growth was at 50 percentile and there was no bowel dilatation. The gallbladder looked normal. Tiny hyperechoic spots scattered on the serosal surface were barely visible.
A male neonate was born by cesarean section (due to previous cesarean section) at 39 weeks. His birthweight was 3050 grams and Apgar scores was 9/9 at 1/5 minutes respectively. Physical examination revealed a healthy newborn. The abdomen was not distended and meconium passed on the day 2. An abdominal ultrasound performed on day 3 revealed only some hyperechoic spots on the Glisson’s capsule.
Sweat-chloride test for cystic fibrosis was negative. Karyotyping resulted in normal karyotype (46, XY). 18 months after delivery the bay is thriving well.