Meconium peritonitis in trisomy 21 masquerading as hydrops fetalis.

Meconium peritonitis (MP) is a rare etiology for nonimmune hydrops fetalis. We report a neonate delivered at 32 weeks' gestation in the context of antenatally diagnosed hydrops fetalis and first-trimester screening at high risk for Trisomy 21. The postnatal abdominal radiograph was striking for gross ascites, the paucity of bowel gas, and widespread calcifications, suggestive of MP and chromosomal analysis confirmed Trisomy 21. Exploratory laparotomy performed on day 3 of life revealed a large pseudocyst, ileal atresia with ileal perforation. MP masquerading as nonimmune hydrops fetalis in Trisomy 21 with ileal atresia is an extremely rare presentation, seldom reported in the literature. [ABSTRACT FROM AUTHOR]