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Importance Rapid whole-genome sequencing (WGS) has advanced inpatient genetic diagnosis, although most evidence comes from neonatal and pediatric intensive care unit (ICU) populations. Its utility for pediatric neurology inpatients across broader acute settings remains insufficiently established. Objective To assess the diagnostic yield, clinical impact, and factors associated with phenotype-concordant rapid WGS diagnoses. Design, Setting, and Participants This was a retrospective cohort study conducted from June 1, 2022, through January 17, 2026, at a tertiary medical center. Pediatric inpatients in the neonatal ICU, pediatric ICU, or general floor with an unexplained neurologic presentation were included. Those with established nongenetic etiology were excluded from analyses. Exposures Trio (77.8%), duo (9.1%), or singleton (13.1%) rapid WGS. Main Outcomes and Measures The primary outcome was the initial phenotype-concordant diagnostic yield at the point of care. Secondary outcomes were reanalysis yield (new diagnoses from reinterpreting nondiagnostic cases prompted by a new unexplained phenotype or family request), cumulative yield, and management change. Associations were assessed by logistic regression (odds ratios [ORs] and 95% CIs). Results Among 175 children (median [IQR] age, 4 months [1 day-4 years]; 93 male [53.1%]) who met inclusion criteria (82 neonates, 93 nonneonates), initial rapid WGS established a phenotype-concordant diagnosis in 79 (45.1%), higher in nonneonates (49 of 93 [52.7%]) than neonates (30 of 82 [36.6%]). Preliminary results returned at mean (SD) 4.0 (1.6) days and final reports at 10.4 (4.5) days. Positive nonconcordant findings occurred in 33 children (18.9%). Reanalysis of 14 nondiagnostic cases yielded 3 additional diagnoses, for a cumulative yield of 82 of 175 children (46.9%). Most diagnoses were monogenic (63 [76.8%]). Management changed in 54 of 82 phenotype-concordant cases (65.9%; 53 at the point of care, 1 after reanalysis) and 8 of 33 (24.2%) positive nonconcordant cases. Family history was most strongly associated with diagnosis (adjusted OR [aOR], 6.46; 95% CI, 3.23-12.93; P < .001), followed by multisystem involvement (aOR, 2.85; 95% CI, 1.24-6.54; P = .01) and congenital anomaly or dysmorphism (aOR, 2.47; 95% CI, 1.07-5.68; P = .03). Hypotonia was most strongly associated in neonates (OR, 20.63; 95% CI, 5.46-77.87; P < .001); ICU admission (OR, 10.25; 95% CI, 2.79-37.67; P < .001) predominated in nonneonates. Conclusions and Relevance Results of this cohort study suggest that rapid WGS diagnosed nearly half of pediatric neurology inpatients and changed management in two-thirds of diagnosed cases, supporting its potential use as early diagnostic testing. Associated features may guide patient selection, and reanalysis extends yield longitudinally.

ABSTRACT Bardet‐Biedl syndrome (BBS) is a rare autosomal recessive disorder characterized by clinical and genetic heterogeneity. Data on the prevalence of clinical manifestations and comorbidities in BBS, particularly in pediatric patients, are limited. This study aimed to assess the prevalence and various manifestations of endocrine and other clinical comorbidities among pediatric and adult patients with BBS. This retrospective chart review included pediatric and adult patients with BBS evaluated at an academic tertiary care center in the United States between 2000 and 2024. The study included 31 patients (7 children and 24 adults) with seven identified pathogenic variants associated with BBS. The most common genetic etiology was biallelic variants in BBS1 (36%). Obesity was diagnosed in 86% of children and 100% of adults. No children had diabetes or prediabetes, whereas 46% of adults were affected. Dyslipidemia was identified in 29% of children and 46% of adults. No thyroid abnormalities were identified in children, whereas 25% of adults were affected. Retinal dystrophy was present in 71% of children and 96% of adults. Polydactyly was observed in 100% of children and 75% of adults. Chronic kidney disease was present in 29% of children and 63% of adults. This study highlights the clinical heterogeneity and substantial multisystem burden of BBS across pediatric and adult patients. The greater prevalence of diabetes/prediabetes, dyslipidemia, thyroid abnormalities, chronic kidney disease, and visual impairment among adults suggests that these complications may emerge or progress over time. Early recognition, proactive longitudinal surveillance, and comprehensive multidisciplinary care are essential to optimize management across the lifespan.

Pediatric genetic and metabolic liver diseases comprise a broad spectrum of conditions and represent the second most common indication for liver transplantation following biliary atresia. The decision to transplant can be challenging and requires consideration of several factors, including hepatic involvement, extrahepatic manifestations, and anticipated posttransplant outcomes. This review examines pediatric genetic and metabolic liver diseases, their pathophysiology, clinical presentation, and the role of liver transplantation.

Sonic hedgehog signaling regulates processes of embryonic development across multiple tissues, yet factors regulating context-specific Shh signaling remain poorly understood. Exome sequencing of families with polymicrogyria (disordered cortical folding) revealed multiple individuals with biallelic deleterious variants in TMEM161B , which encodes a multi-pass transmembrane protein of unknown function. Tmem161b null mice demonstrated holoprosencephaly, craniofacial midline defects, eye defects, and spinal cord patterning changes consistent with impaired Shh signaling, but were without limb defects, suggesting a CNS-specific role of Tmem161b. Tmem161b depletion impaired the response to Smoothened activation in vitro and disrupted cortical histogenesis in vivo in both mouse and ferret models, including leading to abnormal gyration in the ferret model. Tmem161b localizes non-exclusively to the primary cilium, and scanning electron microscopy revealed shortened, dysmorphic, and ballooned ventricular zone cilia in the Tmem161b null mouse, suggesting that the Shh-related phenotypes may reflect ciliary dysfunction. Our data identify TMEM161B as a regulator of cerebral cortical gyration, as involved in primary ciliary structure, as a regulator of Shh signaling, and further implicate Shh signaling in human gyral development.