Israel Medical Association Journal

Inborn errors of immunity (IEI) result from pathogenic germline variants. These disorders are clinically characterized by increased susceptibility to infections and immune dysregulation, often leading to reduced survival [1]. By linking specific monogenic defects to immune phenotypes, IEI serve as experiments of nature that provide powerful models for dissecting human immunology [2]. The International Union of Immunological Societies (IUIS) currently classifies IEI into 10 major categories with overlapping phenotypes [3]: combined T- and B-cell immunodeficiencies, combined immunodeficiencies with syndromic features, predominantly antibody deficiencies, diseases of immune dysregulation, congenital defects of phagocytes, defects in intrinsic and innate immunity, autoinflammatory diseases, complement deficiencies, bone marrow failure, and phenocopies of IEIs. The recent 2024 IUIS update was designed to serve clinicians and researchers and to inform the design of targeted sequencing panels that facilitate the genetic diagnosis of IEI. It lists 508 genes underlying 559 conditions [3]. Of note, molecular, cellular, and clinical investigations of IEI have transformed our understanding of disease pathogenesis and enabled effective targeted therapies.

Inborn errors of immunity (IEI) are a heterogeneous group of monogenic disorders affecting immune function, associated with a broad clinical spectrum including recurrent infections and immune dysregulation consisting of poly-autoimmunity, multiple allergies, and malignancies. To date, more than 550 causative genes have been identified, with inheritance patterns that may be autosomal dominant, autosomal recessive, or X-linked. Pathogenic variants may result in loss-of-function, dominant-negative, or gain-of-function effects, leading to variable phenotypic presentations and, at times, incomplete penetrance. Despite advances in genomic technologies, a definitive molecular diagnosis is reached in only 30–35% of cases. Early and accurate genetic diagnosis is crucial for guiding targeted therapy and providing effective genetic counseling. This review presents an updated overview of IEI from the geneticist's perspective and offers a practical approach to the genetic evaluation and diagnosis of these conditions.

Background: Nasal polyps are three-dimensional structures arising from the mucosa of the upper airway. Due to their complexity, the reliability of single-layer cell cultures and animal systems as research models is limited.

Objectives: To evaluate the feasibility of an ex vivo organ culture of human polyps, preserving tissue structure and function.

Methods: Nasal polyps were excised during routine endoscopic sinus surgery for chronic rhinosinusitis and polyposis. Fresh tissue samples were used for pathological evaluation and for the preparation of 250–500 µm sections, which were incubated in culture media. Tissue viability was assessed by visualisation of cilia motility, measurement of glucose uptake, and an infectivity assay. Cytokine secretion was evaluated by enzyme-linked immunosorbent assay and real-time polymerase chain reaction before and after the introduction of steroids.

Results: Polyp tissue viability was retained for 2–3 days as demonstrated by cilia motility, glucose uptake and preserved cellular composition. Tissue samples maintained their capacity to respond to infection by herpes simplex virus 1 and adenovirus. Introduction of dexamethasone to cultured tissue samples led to suppression of interferon-g production.

Conclusions: The ex vivo nasal polyp organ culture reproduces the physiological, metabolic, and cellular features of nasal polyps. Furthermore, it shows a preserved capacity for viral infection and response to drugs. This system is a useful tool for the investigation nasal-polyps and for the development of novel therapies.

Background: Eosinophilic fasciitis (EF) is a rare disease characterized by scleroderma-like skin, inflammation of deep muscle fascia, hypergammaglobulinemia, peripheral eosinophilia, and elevated erythrocyte sedimentation rate.

Objectives: To present our experience in diagnosis and treatment of seven biopsy-proven EF patients in a large tertiary medical center.

Methods: We screened all patients who were admitted to our tertiary medical center and diagnosed with EF by tissue biopsies from January 2000 to January 2016. We analyzed relevant patient files regarding diagnosis, treatment, and outcome parameters. A comprehensive framework was presented based on the results of our observations and the corresponding literature.

Results: We identified seven patients (six males; one child). Mean age at diagnosis was 37.4 years (range 10–67 years). Underlying autoimmune disorders were observed in three patients (42.8 %). Disease anatomical distribution was noted in lower and upper limbs (85.7% and 57.1%, respectively) as well as neck and shoulders (14.3% each). Three patients (42.8%) had a history of initial misdiagnosis. The mean time period from first clinical presentation to histopathological diagnosis was 150.3 days (range 16–602 days). Treatment included oral glucocorticoids (71.4%), pulse methylprednisolone (14.2%), and methotrexate (42.8%). Recovery from symptoms related to EF was observed in six patients.

Conclusions: Diagnosis of EF is primarily based on clinical and histopathological findings. As eradication of this disease can be expedited with early treatment, it is important to increase awareness in the medical community.