Embryogenesis and types of subcostal hernia--a rare entity.

Background/purpose: Four infants with congenital subcostal hernia are reported, as it is a rare entity with only two cases previously reported. Further, there are no reports concerning the complex multisystem subtype. Embryogenesis of the associated anomalies and subcostal hernia and their management are discussed.

Materials/methods: Clinical features, history, investigations, associated anomalies, and management data of four patients with subcostal hernia were collected and analyzed.

Results: The following associated anomalies were detected: renal agenesis (2), musculoskeletal abnormality (3), congenital heart disease (2), müllerian-renal-cervicothoracic somite abnormalities and vertebral-anorectal-cardiac-tracheoesophageal-renal-radial-limb anomalies (1). The subcostal hernias were treated by laparoscopic assisted (3) or laparoscopic herniorrhaphy (1).

Conclusions: Subcostal hernia is a rare entity with varied clinical presentations and presents either as an isolated defect or as a complex multisystem defect. The exact etiology is still unknown. Phenotypic manifestation of the complex defect is probably due to developmental gene defect affecting the coordinated growth of mesoderm around 4th to 10th weeks of fetal life.