Squire, Jacqueline D.

Down syndrome (DS), the genetic condition caused by trisomy 21 (T21), is characterized by lifelong immune dysregulation leading to high rates of autoimmune disorders, elevated risk of complications from infections, immune hypersensitivity, and a unique form of immunodeficiency. It is now appreciated that DS shares key hallmarks with interferonopathies, with vast remodeling of all branches of the immune system, hypercytokinemia, and widespread autoantibody production. Here within, we review the existing literature with an emphasis on clinical considerations toward monitoring, management, and therapeutic opportunities. We highlight recent research advances that illuminate diagnostic approaches to evaluate immune dysregulation in DS. We also discuss the evidence supporting specific immunomodulatory strategies that could have multidimensional benefits in this population, including JAK inhibitors, intravenous immunoglobulin, and B cell–depleting agents.

Background A substantial proportion of patients with chronic rhinosinusitis (CRS) remain partly controlled or uncontrolled despite endoscopic sinus surgery (ESS) and maximal medical therapy. For these difficult-to-treat cases, topical antibiotic irrigations have been proposed as an adjunctive therapy, particularly when delivered via large-volume, low-pressure systems that enhance sinus penetration post-ESS. Evidence on their efficacy and prescribing patterns in this population remains limited. Objective This study aims to evaluate the use and outcomes of topical antibiotic irrigations in patients with difficult-to-treat CRS. Methods A retrospective, multi-site cohort study was conducted across tertiary academic medical centers. Adult patients with persistent CRS symptoms despite bilateral full-house ESS and conventional postoperative medical management were included. Patients with cystic fibrosis or granulomatosis with polyangiitis were excluded. Demographic, clinical, and treatment data were collected. Primary outcomes were infection resolution at 8 weeks and changes in Sino-Nasal Outcome Test-22 (SNOT-22) scores. Results Sixty-seven patients met inclusion criteria. Mupirocin (41.8%), tobramycin (23.9%), and gentamicin (17.9%) were the most commonly prescribed agents. After 8 weeks, 62.7% of patients achieved infection clearance. Among 44 patients with SNOT-22 data, scores improved significantly from 34.8 ± 20.2 to 21.8 ± 14.7 ( P < .001). Improvement in SNOT-22 scores was more pronounced in patients who cleared the infection compared to those who did not. Conclusion Large-volume topical antibiotic irrigations were associated with high infection resolution rates and clinically meaningful SNOT-22 improvements in patients with difficult-to-treat CRS. These findings support their potential utility as an adjunctive therapy in select postsurgical patients and warrant further prospective investigation.

Acquired angioedema due to C1-inhibitor deficiency (AAE-C1INH) is a rare condition characterized by the localized swelling of the deeper skin layers and mucous membranes, especially the face, lips, tongue, throat, and gastrointestinal tract. AAE-C1INH is strongly associated with lymphoproliferative disorders, although it can also be linked to autoimmune conditions, solid tumors, infections, or even occur without an identifiable cause. We present the case of a 45-year-old female patient with complaints of recurrent abdominal pain, bloating, and joint swelling. Laboratory testing showed decreased C1q and C4 complement levels, and C1 esterase inhibitor levels, indicative of AAE-C1INH. Further work up confirmed a diagnosis of extranodal marginal zone lymphoma with involvement of the bone marrow and spleen. Treatment with rituximab led to resolution of angioedema symptoms and almost complete remission of underlying lymphoma. This case underscores the importance of evaluating an underlying lymphoproliferative disorder in AAE-C1INH. Therefore, the early participation of a multidisciplinary team including specialists in immunology, hematology, and oncology is necessary for appropriate management.

(1) Background: Mutations in NFκB1, a transcriptional regulator of immunomodulating proteins, are a known cause of inborn errors of immunity. Our proband is a 22-year-old male with a diagnosis of common variable immunodeficiency (CVID), cytopenias with massive splenomegaly, and nodular regenerative hyperplasia of the liver. Genetic studies identified a novel, single-point mutation variant in NFκB1, c. T638A p. V213E. (2) Methods: Next-generation panel sequencing of the patient uncovered a novel single-point mutation in the NFκB1 gene that was modeled using the I-TASSER homology-modeling software, and molecular dynamics were assessed using the YASARA2 software (version 20.14.24). (3) Results: This variant replaces valine with glutamic acid at position 213 in the NFκB1 sequence. Molecular modeling and molecular dynamic studies showed altered dynamics in and around the rel homology domain, ankyrin regions, and death domain of the protein. We postulate that these changes alter overall protein function. (4) Conclusions: This case suggests the pathogenicity of a novel variant using protein-modeling techniques and molecular dynamic simulations.

Abstract BACKGROUND Mutations of NFkB1 are a known cause of inborn errors of immunity resulting in immunodeficiency due to the role of NFkB1 as a transcriptional regulator of immunomodulating proteins. We present a patient with a diagnosis of common variable immunodeficiency (CVID), cytopenias with massive splenomegaly, and nodular regenerative hyperplasia of the liver. Our proband, a 22-year-old male, presents with a clinical picture of immunodeficiency, and has a maternal cousin with a similar gene mutation but differing phenotype. Next generation panel sequencing (NGPS) was utilized to discover a novel, single point mutation variant in NFkB1, V213E, that is present in our proband. METHODS The novel single-point mutation V213E in the NFkB gene was modeled in-silico using the I-TASSER homology modeling software. Molecular dynamics simulations of both the wild type and variant mutant form fitted to accommodate the novel mutation were conducted and analyzed to assess for possible pathogenicity of the novel mutation. RESULTS This variant replaces Valine with Glutamic Acid at position 213 in the transcription regulator’s sequence. We perform molecular modeling to analyze the proteomic impact and difference in molecular dynamics (MDS) which depicted suppressed dynamics in the ankyrin region and death domain of the protein complex. Analysis of the proband’s family showed no significant family history except for the maternal cousin with a mutation in NFkB1. CONCLUSION This case both highlights the heterogeneity in phenotype of NFkB1 pathogenic variants as shown in this patient, full penetrance of the variant mutation, and suggests the pathogenicity of a new variant through protein modeling techniques and molecular dynamic simulations.

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency. It is characterized by impaired B-cell differentiation. Although patients can be diagnosed with CVID anytime during their lifetime, most patients have symptoms for 5–9 years before their diagnosis. The diagnosis of CVID starts with a detailed history focusing on the infectious and noninfectious manifestations of the disease. In patients who are suspected to experience CVID, quantitative immunoglobulins (Ig) should be checked to confirm the diagnosis. IgG should be at least 2 times less than the age-specific SD along with either a low IgA or IgM and with evidence of impaired vaccine response. CVID is usually associated with infectious and/or noninfectious conditions, the latter of which can be inflammatory, autoimmune, lymphoproliferative, or malignant, among other manifestations. Ig therapy has positively affected the disease course of patients with infectious complications but has limited effect on the noninfectious manifestations because the noninfectious complications are related to immune dysregulation involving B cells and T cells rather than primarily due to antibody deficiency. When the gastrointestinal (GI) system is involved, patients with CVID may display signs and symptoms that mimic several GI conditions such as celiac disease, pernicious anemia, or inflammatory bowel diseases. The inflammatory bowel disease–like condition is usually treated with steroids, 5-aminosalicylates, thiopurines, or biologic agents to control the inflammation. In this review, the clinical presentations, diagnostic considerations, and therapeutic options for GI manifestations of CVID will be discussed to facilitate the individualized management of these often-complex patients.