Inborn errors of immunity (primary immunodeficiencies).

Primary immunodeficiencies (PID), now often referred to as inborn errors of immunity (IEI), are a large heterogeneous group of disorders that result from deficiencies in immune system development and/or function. IEIs can be broadly classified as disorders of adaptive immunity (e.g.

A Unique Comprehensive Model to Screen Newborns for Severe Combined Immunodeficiency-An Ontario Single-Centre Experience Spanning 2013-2023.

Background: Severe combined immunodeficiency (SCID) is a life-threatening genetic disorder caused by critical defects of the immune system. Almost all cases are lethal if not treated within the first two years of life. Early diagnosis and intervention are thus essential for improving patient outcomes.

Utilization of next-generation sequencing to define the role of heterozygous variants in immunodeficiency.

Background: Forkhead box protein N1 (FOXN1) transcription factor plays an essential role in the development of thymic epithelial cells, required for T-cell differentiation, maturation, and function. Biallelic pathogenic variants in cause severe combined immunodeficiency (SCID). More recently, heterozygous variants in identified by restricted gene panels, were also implicated with causing a less severe and variable immunodeficiency.

Homozygous duplication identified by whole genome sequencing causes LRBA deficiency.

In more than one-third of primary immunodeficiency (PID) patients, extensive genetic analysis including whole-exome sequencing (WES) fails to identify the genetic defect. Whole-genome sequencing (WGS) is able to detect variants missed by other genomics platforms, enabling the molecular diagnosis of otherwise unresolved cases. Here, we report two siblings, offspring of consanguineous parents, who experienced similar severe events encompassing early onset of colitis, lymphoproliferation, and hypogammaglobulinemia, typical of lipopolysaccharide-responsive and beige-like anchor (LRBA) or cytotoxic T lymphocyte antigen 4 (CTLA4) deficiencies.

Basophil activation test shows high accuracy in the diagnosis of peanut and tree nut allergy: The Markers of Nut Allergy Study.

Background: Peanut and tree nut allergies are the most important causes of anaphylaxis. Co-reactivity to more than one nut is frequent, and co-sensitization in the absence of clinical data is often obtained. Confirmatory oral food challenges (OFCs) are inconsistently performed.

Approach to the Assessment and Management of Pediatric Patients With Atopic Dermatitis: A Consensus Document. Section IV: Consensus Statements on the Assessment and Management of Pediatric Atopic Dermatitis.

This document is intended to provide practical guidance to physicians treating pediatric atopic dermatitis (AD), especially dermatologists, pediatricians, allergists, and other health-care professionals. The recommendations contained here were formalized based on a consensus of 12 Canadian pediatric dermatologists, dermatologists, pediatricians, and pediatric allergists with extensive experience managing AD in the pediatric population. A modified Delphi process was adopted with iterative voting on a 5-point Likert scale, with a prespecified agreement cutoff of 75%.

Hematopoietic stem cell transplantation in patients with gain-of-function signal transducer and activator of transcription 1 mutations.

Background: Gain-of-function (GOF) mutations in signal transducer and activator of transcription 1 (STAT1) cause susceptibility to a range of infections, autoimmunity, immune dysregulation, and combined immunodeficiency. Disease manifestations can be mild or severe and life-threatening. Hematopoietic stem cell transplantation (HSCT) has been used in some patients with more severe symptoms to treat and cure the disorder.