611 - National Multidisciplinary Survey of Genetic Testing Practices for Congenital Diaphragmatic Hernia within the Children’s Hospitals Neonatal Consortium

Publication Number: 4598.611

Zachary A. Whitt, Emory University School of Medicine, Atlanta, GA, United States; Sarah Keene, Emory/Childrens Healthcare Of Atlanta, Decatur, GA, United States; DonnaMaria E. Cortezzo, Connecticut Children's Medical Center, Hartford, CT, United States; David McCulley, University of California, San Diego School of Medicine, San Diego, CA, United States; Sandy Johng, Seattle Children's, Seattle, WA, United States; K. Taylor Wild, Children’s Hospital of Philadelphia, Philadelphia, PA, United States; Sharada Hiranya. Gowda, Baylor College of Medicine, Houston, TX, United States; Syed T. Ahmed, University of Texas Southwestern Medical School, Dallas, TX, United States; Michelle J. Yang, University of Utah School of Medicine, Salt Lake City, UT, United States; Katrin Lichtsinn, Seattle Children's, Seattle, WA, United States; Mihai Puia-Dumitrescu, University of Washington School of Medicine, Seattle, WA, United States; Kelsey A. Montgomery, Riley Hospital for Children at Indiana University Health, Indianapolis, IN, United States

Background: Approximately 20-30% of patients with congenital diaphragmatic hernia (CDH) have an identifiable genetic etiology. Identification of a genetic condition in these patients can improve the accuracy of estimating their prognosis and develop patient-specific treatment plans. Despite these benefits, there are no formal guidelines or recommendations for genetic testing for patients with CDH.

Objective: Our objective was to investigate the current genetic testing practices for neonates with CDH and determine how genetic testing results affect patient care through a national multidisciplinary survey of providers within the Children's Hospitals Neonatal Consortium (CHNC).

Design/Methods: A multi-phasic REDCap survey underwent pretesting and pilot testing by experts in the field from multiple centers. The survey was distributed to CHNC site sponsors for dissemination to sub-specialists at their institutions between April and July 2025. Data were analyzed using Fisher's Exact or Chi-squared tests.

Results: 103 individuals from 26 centers responded. Respondents included neonatologists (47%), geneticists (12%), pediatric surgeons (11%), cardiologists (9%) and other sub-specialists. Sixty-three percent of respondents indicated they send genetic testing for all patients with CDH; however, some centers rarely or never send genetic testing for these patients. Chromosomal microarray (CMA) was the most commonly ordered test (62%). Geneticists and genetic counselors were often involved in ordering testing, but many indicated that testing might be sent before they were involved. Forty-nine percent of respondents stated that identification of a genetic condition alters medical decision-making leading to additional consults/referrals, discussion of comfort care, and additional surgical interventions. The most common barriers to testing were parental preference and lack of guidelines for genetic testing. Seventy-eight percent did not have or were unsure if they had a CDH genetic testing algorithm.

Conclusion(s): In this large national multidisciplinary survey, most neonates with CDH are offered genetic testing; however, there is wide variation between and even within centers regarding the timing, type of testing, and considerations about how genetic testing results impact treatment. Given the potential impact of making a genetic diagnosis in patients with CDH and the improved availability of rapid whole genome sequencing, there is a need for genetic testing consensus guidelines to ensure the highest quality of care for patients with CDH.

Figure 1: Inpatient Respondent Specialty
This data shows the total population who took the survey and the respective breakdown of subspecialties. This demonstrates the diversity of perspectives included in this cohort.

Figure 2: Inpatient Testing Modality Selection
In this figure, we show that the majority of providers select CMA as the primary testing modality. Selection of other tests is variable.

Figure 3: Changes in Medical Decision Making
This figure demonstrates the changes in medical decision making that would be made if the patient with CDH has a confirmed genetic syndrome on testing.