Inborn errors of immunity: Recent progress.

Recent advances in the field of inborn errors of immunity (IEIs) have been wide in scope, including progress in mechanisms of disease, diagnosis, and management. New gene defects affecting the immune response continue to be reported, as many as 26 in the year 2020. It was noted that the presentation of IEIs might not include recurrent infections in 9% of cases, and that current diagnostic methods can identify molecular causes in 92% of patients with severe combined immunodeficiency. Progress in immunopathogenesis explained mechanisms leading to symptoms of autosomal-recessive hyper-IgE syndrome. There was an emphasis on research in primary antibody deficiencies. The benefit of antibiotic prophylaxis to reduce the frequency of infections was demonstrated in these patients. The regimen of rituximab and azathioprine or mycophenolate was proven effective for chronic granulocytic interstitial pneumonia. The efficacy and adverse events of hematopoietic stem cell transplant in different IEI conditions were reported, as well as different strategies to improve outcomes, supporting its use in immunodeficiency and immunodysregulatory syndromes. The recent pandemic of coronavirus disease 2019 affected patients with IEIs, in particular those with deficiency in the interferon-mediated activation of the immune response. Initial data suggest that coronavirus disease 2019 vaccines might elicit anti-coronavirus disease 2019-neutralizing antibody responses in some patients with IEI conditions.

Secondary immunodeficiencies: An overview.

OBJECTIVE: To review the different causes of secondary immunodeficiencies and provide clinicians with an updated overview of potential factors that contribute to immunodeficiency. DATA SOURCES: Recent published literature obtained through PubMed database searches, including research articles, review articles, and case reports. STUDY SELECTIONS: PubMed database searches were conducted using the following keywords: immunodeficiency, antibody deficiency, immunosuppressive drugs, genetic syndrome, malignancy, HIV infection, viral infection, secondary immunodeficiency, nutrition, prematurity, aging, protein-losing enteropathy, nephropathy, trauma, space travel, high altitude, and ultraviolet light. Studies published in the last decade and relevant to the pathogenesis, epidemiology, and clinical characteristics of secondary immunodeficiencies were selected and reviewed. RESULTS: Researchers continue to investigate and report abnormal immune parameters in the different entities collectively known as secondary immunodeficiencies. Immunodeficiency might occur as a consequence of malnutrition, metabolic disorders, use of immunosuppressive medications, chronic infections, malignancies, severe injuries, and exposure to adverse environmental conditions. The neonate and the elderly may have decreased immune responses relative to healthy adults. Each of these conditions may present with different immune defects of variable severity. The acquired immunodeficiency syndrome results from infections by the human immunodeficiency virus, which targets CD4 T cells leading to defective immune responses. Rituximab is a monoclonal antibody that targets CD20 B cells, and its use might result in persistent hypogammaglobulinemia. CONCLUSION: Clinicians should consider secondary immunodeficiencies in the differential diagnosis of a patient with recurrent infections and abnormal immunologic evaluation. The use of biological agents for the treatment of inflammatory conditions and malignancies is an increasingly important cause of secondary immunodeficiency.

Utility of Component-Resolved Diagnostics in Food Allergy.

Allergen component-resolved diagnostic testing (CRD) is a new methodology in clinical food allergy diagnosis, improving the ability to identify specific clinical phenotypes. Instead of relying on the crude allergen extracts used in standard allergy diagnostics, CRD utilizes purified or recombinant allergens for identification of specific molecules causing sensitization or allergy. This method is able to determine risk of the severity of allergic reactions in specific cases, like soy, peanut, and hazelnut allergy. The severity of allergic reaction can be predicted in peanut allergy with Ara h 2, and clinically relevant disease in pollen-allergic patients can be identified. However, age and geographic differences affect CRD results and it should always be utilized in the context of a clinical history. In the future, clinical phenotypes may be differentiated with larger prospective studies utilizing food challenges.