Longitudinal Follow-Up with Radiologic Imaging Is Essential for Detection of Recurrence in Patients with Congenital Diaphragmatic Hernia - Results from a Large Prospective Cohort-Study at a Single Referral Centre

Background: Congenital diaphragmatic hernia is a rare and still challenging malformation with long-term-morbidity gaining more importance. Recurrence is reported in up to 50% after patch-implantation. Previous studies are difficult to compare, because surgical techniques differ, most are retrospective and do neither offer longitudinal follow-up nor radiologic imaging to all survivors. This is a large prospective cohort-study from one institution with a standardized surgical treatment-algorithm and a structured long-term follow-up to allow a reliant detection of recurrence-rate and determination of risk-factors. Methods: Data was collected over 12 years with a minimal follow-up of two years. 508 neonates with congenital diaphragmatic hernia were treated, 410 patients survived, and 90% were followed longitudinally. Findings: In open surgery 68 patients received a primary repair and 251 a cone-shaped patch. Recurrence after open surgery occurred in three patients until discharge, in 28 children thereafter. Six patients developed re-recurrences. Overall 38 recurrences were diagnosed (24 ‘true’ recurrences, eight hiatal hernias, six combined recurrences). Recurrence-rate after primary repair was 8.8% and 12.7% after repair with a cone-shaped patch (p=0.53). Recurrence was significantly associated with initial defect-size. Independent risk-factors for recurrence were a left-sided defect, intrathoracic liver-herniation, and the need for an abdominal wall patch. Interpretation: Long-term-results after diaphragmatic reconstruction highly depend on surgical technique. A reduced recurrence-rate in open surgery can even be achieved in a referral centre with predominantly large defects by implantation of a cone-shaped patch. It is essential to follow all patients longitudinally with regular radiologic imaging – since most showed no or minimal symptoms (97%) and because 45% of recurrences were diagnosed beyond one year of age. Only longitudinal follow-up with radiologic imaging of all patients allows a reliant detection of recurrence to prevent acute incarceration and chronic failure to thrive with their impact on prognosis. Funding Statement: There was no funding for this study. Declaration of Interests: KBZ, TS, MW and CW do not disclose any financial or personal conflict of interests. LMW received personal fees for his work in the Advisory Board Shire (intestinal failure in children due to short bowel syndrome) and for his lecture on pediatric surgery in neonatology (Chiesi). Ethics Approval Statement: This study was approved by our local ethic committee and informed consent was obtained from parents.