United States Public Health Laboratory Experiences with Krabbe Disease Newborn Screening After Recommendation at the National Level

Krabbe disease (KD) is a rare, inherited leukodystrophy associated with early mortality. Infantile Krabbe disease (IKD) was added to the Recommended Uniform Screening Panel (RUSP) in July 2024. Since then, U.S. states have continued to evaluate implementing KD newborn screening (NBS), and RUSP inclusion has hastened adoption efforts. This study aimed to characterize NBS program responses to this recommendation and identify factors influencing adoption and implementation. A mixed-methods approach was used, including a case review of Wisconsin’s process to add conditions to its NBS panel and a cross-sectional survey of U.S. NBS programs. Responses were obtained from 50 of 51 NBS programs. Twenty-two programs actively screen for KD, with ten additional programs in the implementation process. Screening approaches varied, particularly in psychosine (PSY) cutoff thresholds and testing algorithms. Programs reported a range of adoption pathways, including legislative mandates, advisory committee review, and state-specific nomination processes. Key factors impacting KD NBS adoption included uncertainty regarding treatment safety, efficacy, and availability, ethical considerations related to identifying later-onset disease, and logistical challenges such as laboratory readiness and clinical follow-up resources. This study provides a contemporary overview of national implementation of KD NBS and offers practical insights for programs considering adoption.