Prenatal Diagnosis of Congenital Paraesophageal Hernia With Gastric Volvulus and Postnatal FBN1 Mutation Confirmation.

We report a case of a fetus with a congenital paraesophageal hernia (CPEH) with suspected volvulus and a paternal history of Marfan syndrome (MFS). The patient was followed by a multidisciplinary team with plans for postnatal surgical intervention and genetic testing. Postnatal examination confirmed CPEH with gastric volvulus, requiring surgical repair on the first day of life. Neonatal genetic analysis detected a paternally inherited heterozygous pathogenic variant in FBN1, associated with MFS. Prenatal ultrasound findings of CPEH and volvulus have seldom been reported as associations with fetal MFS. This case highlights a rare association and the importance of proactive planning and early surgical intervention.