Siblings With Thrombocytopenia Found To Have a Pathogenic Variant in the NFkB1 Gene.

Immune thrombocytopenic purpura is one of the most common causes of low platelet count in the pediatric population. Secondary thrombocytopenia has a wide differential diagnosis in children, including rheumatological, hematological, and immunological etiologies. Underlying etiologies must be excluded if suspected before labeling the patient as primary thrombocytopenia. Here, we report two siblings with persistent and profound thrombocytopenia. A 10-year-old girl presented with profound and treatment-refractory thrombocytopenia. Given the patient's family history of thrombocytopenia of unknown pathology in her older brother, immune dysregulation-related thrombocytopenia was suspected. Whole exome sequencing confirmed a previously reported pathogenic variant in the NFKB1 gene linked to common variable immunodeficiency 12 (CVID-12) diagnosis for both patients.

Practice Patterns and Approach to Childhood Lupus Nephritis in Saudi Arabia.

Renal involvement of systemic lupus erythematosus needs aggressive treatment. Despite the development of multiple international guidelines, differences in practices exist. This study aimed to explore the current practices of pediatric rheumatologists and nephrologists for the diagnosis, management, and monitoring of lupus nephritis (LN) in Saudi Arabia through a survey. Among the 61 respondents, 54.1% were pediatric nephrologists and 49.9% were pediatric rheumatologists. Predominantly, the participating physicians received training either nationally (57%) or in North America (45%). Most of the respondents (77%) did not have a combined rheumatology-nephrology clinic, primarily because of space or time limitations (75%), or a lack of the other specialty (13%). In terms of the decision to request a renal biopsy, the most common factors were nephrotic-range proteinuria (85%) and a lower level of proteinuria associated with hypocomplementemia or elevated anti-double-stranded (ds) DNA (73%). There was marginal agreement over monitoring the disease's activity and treatment response; Complements 3 and 4, anti-dsDNA, protein-creatinine ratio, and estimated glomerular filtration rate were the most popular parameters. The main reason for repeating a renal biopsy was a new renal manifestation that was inconsistent with the previous biopsy. There was considerable variability in the induction therapies used to initiate and taper corticosteroids and conventional immunosuppressive drugs. Most respondents (91%) used angiotensin-converting enzyme agents to control proteinuria. Considerable agreement exists among Saudi physicians managing children with LN but significant variations exist regarding the therapeutic strategies. Additional endeavors are needed to establish a unified national clinical approach for managing LN in children.

Phenotypic diversity, disease progression, and pathogenicity of MVK missense variants in mevalonic aciduria.

Mevalonic aciduria (MVA) and hyperimmunoglobulinemia D syndrome (MKD/HIDS) are disorders of cholesterol biosynthesis caused by variants in the MVK gene and characterized by increased urinary excretion of mevalonic acid. So far, 30 MVA patients have been reported, suffering from recurrent febrile crises and neurologic impairment. Here, we present an in-depth analysis of the phenotypic spectrum of MVA and provide an in-silico pathogenicity model analysis of MVK missense variants. The phenotypic spectrum of 11 MVA patients (age range 0-51 years) registered in the Unified European Registry for Inherited Metabolic Disorders database was systematically analyzed using terms of the Human Phenotype Ontology. Biochemical, radiological as well as genetic characteristics were investigated. Six of eleven patients have reached adulthood and four have reached adolescence. One of the adolescent patients died at the age of 16 years and one patient died shortly after birth. Symptoms started within the first year of life, including episodic fever, developmental delay, ataxia, and ocular involvement. We also describe a case with absence of symptoms despite massive excretion of mevalonic acid. Pathogenic variants causing MVA cluster within highly conserved regions, which are involved in mevalonate and ATP binding. The phenotype of adult and adolescent MVA patients is more heterogeneous than previously assumed. Outcome varies from an asymptomatic course to early death. MVK variants cluster in functionally important and highly conserved protein domains and show high concordance regarding their expected pathogenicity.