Defining clinical subgroups and genotype-phenotype correlations in NBAS-associated disease across 110 patients.

PURPOSE: Pathogenic variants in neuroblastoma-amplified sequence (NBAS) cause an autosomal recessive disorder with a wide range of symptoms affecting liver, skeletal system, and brain, among others. There is a continuously growing number of patients but a lack of systematic and quantitative analysis. METHODS: Individuals with biallelic variants in NBAS were recruited within an international, multicenter study, including novel and previously published patients. Clinical variables were analyzed with log-linear models and visualized by mosaic plots; facial profiles were investigated via DeepGestalt. The structure of the NBAS protein was predicted using computational methods. RESULTS: One hundred ten individuals from 97 families with biallelic pathogenic NBAS variants were identified, including 26 novel patients with 19 previously unreported variants, giving a total number of 86 variants. Protein modeling redefined the ß-propeller domain of NBAS. Based on the localization of missense variants and in-frame deletions, three clinical subgroups arise that differ significantly regarding main clinical features and are directly related to the affected region of the NBAS protein: ß-propeller (combined phenotype), Sec39 (infantile liver failure syndrome type 2/ILFS2), and C-terminal (short stature, optic atrophy, and Pelger-Huët anomaly/SOPH). CONCLUSION: We define clinical subgroups of NBAS-associated disease that can guide patient management and point to domain-specific functions of NBAS.

Diagnostic value of plasma lysosphingolipids levels in a Niemann-Pick disease type C patient with transient neonatal cholestasis.

OBJECTIVES: Niemann-Pick disease type C (NPC) is a lysosomal storage disease due to impaired intracellular lipid trafficking caused by biallelic pathogenic variants in NPC1 or NPC2 genes. NPC is classified according to the age of onset of neurological manifestations. Cholestatic liver disease can be transient or lead to liver failure. Accompanying neurological findings can be observed at any age. In this report, an infant with a homozygous pathogenic variant in NPC1 gene whose diagnosis was eventually confirmed by specific biomarkers is described. CASE PRESENTATION: A sixteen-day-old male was admitted to hospital with prolonged jaundice. He had mild hepatosplenomegaly, conjugated hyperbilirubinemia, elevated liver transaminases, and mild hypoalbuminemia. Cholestasis resolved spontaneously and patient was readmitted due to progressive hepatosplenomegaly without any neurologic findings when he was 8 months old. Molecular investigations detected homozygous c.1123A > C (p.Thr375Pro) pathogenic variant in NPC1 gene. NPC-specific lysosomal biomarkers such as Lysosphingomyelin and Lysosphingomyelin-509 were elevated, confirming the diagnosis. CONCLUSIONS: The clinical features of NPC are highly heterogeneous, from disease severity or age of onset to disease progression. Patients presenting with transient neonatal cholestasis and should be regularly followed for neurodevelopmental status and visceromegaly. In the case of variants of unknown significance in NPC1 gene, lysosomal biomarkers play an important role when genetic analyses are inconclusive.

Obstructive jaundice and severe pancreatitis due to the foramen of Winslow hernia with multiple anomalies.

Internal hernia through the foramen of Winslow is a very rare condition, especially in children. Here we report a 16-month-old girl who presented with obstructive jaundice and elevation of pancreatic enzymes and was ultimately diagnosed with internal hernia and malrotation by radiologic investigation and open approach surgery. To the best of our knowledge, obstructive jaundice with pancreatitis and other congenital abnormalities in children with the foramen of Winslow hernia have not been reported previously in the literature.