Newborn screening (NBS) in the United States identifies life-threatening conditions early in life and is managed at the state level. Although guided by the Recommended Uniform Screening Panel (RUSP), states may include additional conditions. In April 2024, Ohio became the first state to add Duchenne muscular dystrophy (DMD) to its NBS panel.1 DMD is an X-linked recessive disorder affecting 1 in 3500–5000 male births.2 Pathogenic variants in the DMD gene result in dystrophin deficiency, leading to progressive muscle degeneration, cardiomyopathy, and early death.3 Treatment options include glucocorticoids, Angiotensin-Converting Enzyme (ACE) inhibitors, and physical therapy. Recent advances include exon-skipping therapies and, as of 2023, US Food and Drug Administration approval of the gene therapy delandistrogene moxeparvovec.4 Clinical trials of CRISPR and cell-based therapies are ongoing.5 Early detection through NBS enables timely intervention. Several studies have demonstrated high accuracy in newborn screening for DMD using creatine kinase–MM (CK-MM) dried blood spot testing, a biomarker markedly elevated in DMD.6 Although DMD is not yet on the RUSP, screening has been implemented in Ohio, New York, Minnesota, and Massachusetts.7,8 This report describes CK-MM–based DMD screening implementation in an Ohio community hospital.This retrospective study assessed DMD newborn screening implementation at an Ohio community hospital Ohio from April 22, 2024, to March 31, 2025. All live-born infants underwent CK-MM screening using dried blood spots. Age-specific CK-MM thresholds, detailed in Table 1, were used to classify results as inconclusive or elevated. Infants with elevated or inconclusive results received follow-up CK testing or repeat NBS. Data were stratified by nursery type (neonatal intensive care unit NICU vs newborn nursery) to reflect clinical workflow. Demographics, birth outcomes, and maternal/neonatal complications were reported descriptively but were not used for formal hypothesis testing. All data were collected from medical records. The study was reviewed and deemed exempt by the hospital system’s institutional review board.Between April 2024 and March 2025, 2605 newborns (458 in the NICU and 2147 in the newborn nursery) were screened for DMD using CK-MM. A total of 147/2605 (5.6%) screened positive for elevated CK-MM. Of the 147 newborns with positive sreens, 50% (n = 74) were Black/African American, 37% (n = 54) were White, and 18% (n = 27) were of Hispanic ethnicity; sex was evenly distributed. Most of the positive screens (n = 119, 81%) occurred in preterm newborns. A higher proportion of newborns with positive screens were admitted to the NICU (n = 121, 82%) vs newborn nursery (n = 26, 18%). Seventy-three percent (n = 107) underwent confirmatory plasma CK testing and 27% (n = 40) received a repeat newborn screen. One term male infant was confirmed to have DMD by genetic testing. Complete demographic and clinical data are summarized in Table 2.This is one of the first published studies to demonstrate the successful implementation of NBS for DMD using CK-MM levels in a community hospital setting. These findings are particularly relevant for hospitalists, frequently the first to interpret abnormal NBS results, counsel families, and coordinate confirmatory inpatient testing. In this cohort, 1 in 2605 newborns was diagnosed with DMD following positive CK-MM screening and confirmatory genetic testing. CK-MM testing facilitates early triage and is compatible with routine NBS workflows. However, CK-MM values are influenced by factors such as age, gestational age, and birthweight, as supported by our findings of elevated levels in preterm infants. These findings are consistent with prior work showing wide variability in CK levels across delivery types and clinical contexts, reinforcing that elevated CK-MM is not a specific marker for congenital muscular disease.9 The period of uncertainty for families with positive screens but negative results may have caused parental stress, underscoring the importance of clear communication, anticipatory guidance, and structured counseling during NBS. The lack of standardized CK-MM cutoffs remains a major limitation, and efforts to refine screening algorithms by controlling for demographic and perinatal variables are warranted.6 Importantly, the implementation of DMD NBS has catalyzed broader investigations into early disease progression, including a multicenter natural history study of children under age 3 years.10 These efforts not only inform individual clinical management but also have the potential to shape national policy, including consideration of DMD for inclusion on the federal RUSP. Expanding access to DMD NBS represents a meaningful advance toward equitable early detection of pediatric neuromuscular disorders.
Kumar et al. (Sat,) studied this question.