Background: Genome sequencing (GS) has proven effective in reducing morbidity in critically ill infants, however, equitable access to testing remains a challenge in some populations. This study evaluates the use of GS in critically ill infants in Brazil, focusing on diagnostic yield and clinical utility.
Methods: A national prospective study was conducted through a public-private partnership. GS was performed on infants under one year of age admitted to intensive care units. Clinical utility was evaluated based on physician perception, impact on clinical management, relevance for infants or family members/caregivers, and implications for genetic counseling.
Results: GS was performed on 100 infants, yielding a confirmed molecular diagnosis in 32% of cases. An additional 7% were classified as likely diagnostic, resulting in a potential diagnostic yield of 39%. The median turnaround time was 13 days (7-25 days). Physicians recognized clinical utility for 81.1% of participants. Diagnostic and negative test results impacted clinical management, genetic counseling and/or demonstrated relevance for infants and families in 100% and 86.9% of reports, respectively.
Conclusion: This study represents the largest South American cohort of critically ill infants evaluated by GS and provides a model for national implementation. Assessing clinical utility provided a comprehensive view of GS's impact.
Impact: This article shows that genome sequencing (GS) in critically ill infants has clinical utility beyond diagnostic yield and management changes. Our study provides additional genomic data from a population typically underrepresented in international genomic research. This study represents the largest cohort of critically ill infants evaluated by GS in South America, providing a model for national-level implementation of GS in a resource-constrained setting.
© 2026. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.