The Relationship Between Eosinophilic Esophagitis and Immunotherapy.

Immunotherapy is a treatment approach based on the principle of incremental allergen exposure to achieve desensitization. Recently, oral immunotherapy has been introduced as a treatment of IgE-mediated food allergy. Some patients receiving oral immunotherapy for food allergy may develop eosinophilic esophagitis. Here, we summarize the literature examining this association, its treatment, and outcomes and discuss possible explanations for this clinical phenomenon. We further identify potential associations with aeroallergen sensitivity and other forms of immunotherapy including subcutaneous immunotherapy and sublingual immunotherapy. Finally, we discuss management of immunotherapy-induced eosinophilic esophagitis. Epicutaneous immunotherapy is highlighted as an area of therapeutic investigation.

Coronavirus Disease 2019 mRNA Vaccination Appears Safe in Pediatric Patients With Hypersensitivity to Polyethylene Glycolated Escherichia coli L-asparaginase.

Polyethylene glycol-asparaginase (PEGAsp) is an established component of acute leukemia therapy. Hypersensitivity reactions to PEGAsp occur in 10% to 15% of patients, with polyethylene glycol suggested as the antigenic culprit. As coronavirus disease 2019 (COVID-19) mRNA vaccines contain polyethylene glycol, the safety of administration of these vaccines to patients with prior PEGAsp hypersensitivity has been questioned. Between December 21, 2020 and March 3, 2022, 66 patients with acute leukemia and PEGAsp allergy received COVID-19 vaccination. No patients (0/66 0%, 95% CI: 0%-5.4%) experienced an allergic reaction to the vaccine. COVID-19 mRNA vaccination appears to be safe in pediatric and young adult patients with acute lymphoblastic leukemia with PEGAsp allergy.

Human mutational constraint as a tool to understand biology of rare and emerging bone marrow failure syndromes.

Inherited bone marrow failure (IBMF) syndromes are rare blood disorders characterized by hematopoietic cell dysfunction and predisposition to hematologic malignancies. Despite advances in the understanding of molecular pathogenesis of these heterogeneous diseases, genetic variant interpretation, genotype-phenotype correlation, and outcome prognostication remain difficult. As new IBMF and other myelodysplastic syndrome (MDS) predisposition genes continue to be discovered (frequently in small kindred studies), there is an increasing need for a systematic framework to evaluate penetrance and prevalence of mutations in genes associated with IBMF phenotypes. To address this need, we analyzed population-based genomic data from >125 000 individuals in the Genome Aggregation Database for loss-of-function (LoF) variants in 100 genes associated with IBMF. LoF variants in genes associated with IBMF/MDS were present in 0.426% of individuals. Heterozygous LoF variants in genes in which haploinsufficiency is associated with IBMF/MDS were identified in 0.422% of the population; homozygous LoF variants associated with autosomal recessive IBMF/MDS diseases were identified in only .004% of the cohort. Using age distribution of LoF variants and 2 measures of mutational constraint, LOEUF ("loss-of-function observed/expected upper bound fraction") and pLI ("probability of being loss-of-function intolerance"), we evaluated the pathogenicity, tolerance, and age-related penetrance of LoF mutations in specific genes associated with IBMF syndromes. This analysis led to insights into rare IBMF diseases, including syndromes associated with DHX34, MDM4, RAD51, SRP54, and WIPF1. Our results provide an important population-based framework for the interpretation of LoF variant pathogenicity in rare and emerging IBMF syndromes.