Association of congenital diaphragmatic hernia and hiatal hernia with tetrasomy 18p

•The association of congenital diaphragmatic hernia and hiatal hernia together has not been previously reported in a case of tetrasomy 18p.•An abdominal surgical approach may be favored for diagnosing and repairing both of these defects simultaneously.

We report a case of a newborn with tetrasomy 18p who presents with both a congenital diaphragmatic hernia and a giant hiatal hernia. While these two hernias have been rarely reported together in the newborn period, this represents the first association with the chromosomal abnormality of tetrasomy 18p.