Fetal intra-abdominal calcifications from meconium peritonitis: sonographic predictors of postnatal surgery

OBJECTIVE: To study the relationship between prenatal ultrasound features and postnatal course of meconium peritonitis. STUDY DESIGN: We reviewed our cohort of cases of meconium peritonitis (MP) (n = 13/37, 225 pregnancies or 0.3/1000) as well as those published in the English literature with prenatal ultrasonographic findings and postnatal follow-up (n = 56). The total number of cases (n = 69) was divided into 4 grades of progressive severity based on the number of pertinent sonographic findings: grade 0, isolated intra-abdominal calcifications (n = 18); grade 1, intra-abdominal calcifications and ascites (n = 17) or pseudocyst (n = 2) or bowel dilatation (n = 6); grade 2, two associated findings (n = 20); and grade 3, all sonographic features (n = 6). Presence of polyhydramnios was also recorded. Prenatal predictors of need for neonatal surgery and risk of neonatal death were identified using Chi-square and Fisher exact test, with P < 0.05 considered significant. RESULTS: Neonatal surgical intervention was required in 0% (0/18) of newborns with grade 0 MP; in 52% (13/25) of those with grade 1; in 80% (16/20) with grade 2; and in 100% (6/6) with grade 3 MP (P < 0.001, Chi-square for trend). Moreover, neonatal surgery was more frequent in the presence than absence of polyhydramnios [69% (18/26) vs 37% (16/43); P = 0.007]. Neonatal mortality was 6% (4/69; 3 after surgery and 1 for premature delivery) and it was confined to the subgroup with polyhydramnios (4/26, 15%). CONCLUSIONS: Prenatal sonographic features are related to postnatal outcome. Persistently isolated intra-abdominal calcifications have an excellent outcome. Delivery in a tertiary care center is recommended when calcifications are associated with other sonographic findings.