Diagnostic efficacy and clinical utility of whole-exome sequencing in Czech pediatric patients with rare and undiagnosed diseases.

In the last decade, undiagnosed disease programs have emerged to address the significant number of individuals with suspected but undiagnosed rare genetic diseases. In our single-center study, we have launched a pilot program for pediatric patients with undiagnosed diseases in the second-largest university hospital in the Czech Republic. This study was prospectively conducted at the Department of Pediatrics at University Hospital Brno between 2020 and 2023.

Elevated erythroferrone distinguishes erythrocytosis with inherited defects in oxygen-sensing pathway from primary familial and congenital polycythaemia.

Congenital erythrocytoses represent a heterogenous group of rare defects of erythropoiesis characterized by elevated erythrocyte mass. We performed molecular-genetic analysis of 21 Czech patients with congenital erythrocytosis and assessed the mutual link between chronic erythrocyte overproduction and iron homoeostasis. Causative mutations in erythropoietin receptor (EPOR), hypoxia-inducible factor 2 alpha (HIF2A) or Von Hippel-Lindau (VHL) genes were detected in nine patients, including a novel p.

Two sisters with cardiac-urogenital syndrome secondary to pathogenic splicing variant in the MYRF gene with unaffected parents: A case of gonadal mosaicism?

Background: Cardiac-urogenital syndrome [MIM # 618280] is a newly described very rare syndrome associated with pathogenic variants in the myelin regulatory factor (MYRF) gene that leads to loss of protein function. MYRF is a transcription factor previously associated only with the control of myelin-related gene expression. However, it is also highly expressed in other tissues and associated with various organ anomalies.

Extremely low birthweight neonates with phenylketonuria require special dietary management.

Aim: Extremely low birthweight (ELBW) neonates require a high protein intake, but this can be challenging in the very rare cases when they also have phenylketonuria (PKU). This is due to a lack of suitable parenteral nutrition or enteral formula. Our aim was to analyse tolerance to phenylalanine in these infants.

Two Novel Mutations in the Gene in Pediatric Patients with Alagille Syndrome: The First Case Series in Czech Republic.

Background: Alagille syndrome (ALGS) is a highly variable multisystem disorder inherited in an autosomal dominant pattern with incomplete penetration. The disorder is caused by mutations in the gene, only rarely in the gene, which gives rise to malformations in multiple organs. Bile duct paucity is the main characteristic feature of the disease.