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Chronic granulomatous disease (CGD) is a rare primary immune deficiency caused by mutations in genes coding for components of the nicotinamide adenine dinucleotide phosphate oxidase, characterized by severe and recurrent bacterial and fungal infections, together with inflammatory complications. Dysregulation of inflammatory responses are often present in this disease and may lead to granulomatous lesions, most often affecting the gastrointestinal (GI) and urinary tracts. Treatment of inflammatory complications usually includes corticosteroids, whereas antimicrobial prophylaxis is used for infection prevention. Curative treatment of both infectious susceptibility and inflammatory disease can be achieved by hematopoietic stem cell transplantation. We report herein three patients with the same mutation of the CYBB gene who presented with very early-onset and severe GI manifestations of X-linked CGD. The most severely affected patient had evidence of antenatal inflammatory involvement of the GI and urinary tracts. Extreme hyperleukocytosis with eosinophilia and high inflammatory markers were observed in all three patients. A Mycobacterium avium lung infection and an unidentified fungal lung infection occurred in two patients both during their first year of life, which is indicative of the severity of the disease. All three patients underwent bone marrow transplantation and recovered fully from their initial symptoms. To our knowledge, these are the first reports of patients with such an early-onset and severe inflammatory manifestations of CGD.

Background: Identification of Staphylococcus aureus intracellularly in chronic rhinosinusitis (CRS) suggests an underlying cellular immunodeficiency. Supporting this, we have previously reported low CD8+ (cytotoxic) T-lymphocyte levels in a subpopulation of CRS patients and identified polymorphisms in the CD8A gene associated with CRS. In order to better understand the role of low CD8+ in CRS, we wished to determine the phenotype for CRS/Low CD8+ in comparison to that of conventional CRS., Methods: Sixty-seven low CD8+ CRS patients identified during investigation of CRS were compared for demographics, disease evolution, and bacteriology on endoscopic culture were compared with an existing population of 480 patients with CRS with nasal polyposis previously recruited for genetic association studies., Results: Mean level of CD8+ in the CRS/Low CD8+ population was 0.15 × 10(9)/L (range, 0.20-1.5 × 10(9)/L). There was no difference between both groups in terms of history of allergy, asthma, eczema, acetylsalicylic acid (ASA) intolerance or smoking. The bacteriology was similar between both groups (S. aureus: CRS/Low CD8+: 35%; CRS 32%, p = 0.643). Evolution of disease was somewhat milder in CRS/Low CD8+, with fewer patients requiring surgery, and first surgery performed at a more advanced age. However, antibiotic use was higher in CRS/Low CD8+. Subgroup analysis restricted to CRS with nasal polyposis (CRSwNP)/Low CD8 or CRS without nasal polyposis (CRSsNP)/Low CD8 phenotypes did not substantially alter these results., Conclusion: Low CD8+ levels are often identified in CRS patients; however, these patients have disease remarkably similar to those with conventional CRS. This suggests that immune deficiency, whether systemic or locally mediated, is well tolerated and may be present in other forms in CRS. CRS patients with low CD8+ levels may possibly require antibacterial therapies as part of ongoing management., (© 2014 ARS-AAOA, LLC.)

Background: The recombination-activating gene (RAG) 1/2 proteins play a critical role in the development of T and B cells by initiating the VDJ recombination process that leads to generation of a broad T-cell receptor (TCR) and B-cell receptor repertoire. Pathogenic mutations in the RAG1/2 genes result in various forms of primary immunodeficiency, ranging from T(-)B(-) severe combined immune deficiency to delayed-onset disease with granuloma formation, autoimmunity, or both. It is not clear what contributes to such heterogeneity of phenotypes., Objective: We sought to investigate the molecular basis for phenotypic diversity presented in patients with various RAG1 mutations., Methods: We have developed a flow cytometry-based assay that allows analysis of RAG recombination activity based on green fluorescent protein expression and have assessed the induction of the Ighc locus rearrangements in mouse Rag1(-/-) pro-B cells reconstituted with wild-type or mutant human RAG1 (hRAG1) using deep sequencing technology., Results: Here we demonstrate correlation between defective recombination activity of hRAG1 mutant proteins and severity of the clinical and immunologic phenotype and provide insights on the molecular mechanisms accounting for such phenotypic diversity., Conclusions: Using a sensitive assay to measure the RAG1 activity level of 79 mutations in a physiologic setting, we demonstrate correlation between recombination activity of RAG1 mutants and the severity of clinical presentation and show that RAG1 mutants can induce specific abnormalities of the VDJ recombination process., (Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Background: Defects in the development or activation of T cells result in immunodeficiency associated with severe infections early in life. T-cell activation requires Ca2+ influx through Ca2+-release activated Ca2+ (CRAC) channels encoded by the gene ORAI1., Objective: Investigation of the genetic causes and the clinical phenotype of immunodeficiency in patients with impaired Ca2+ influx and CRAC channel function., Methods: DNA sequence analysis for mutations in the genes ORAI1, ORAI2, ORAI3, and stromal interaction molecule (STIM) 1 and 2, as well as mRNA and protein expression analysis of ORAI1 in immunodeficient patients. Immunohistochemical analysis of ORAI1 tissue distribution in healthy human donors., Results: We identified mutations in ORAI1 in patients from 2 unrelated families. One patient is homozygous for a frameshift nonsense mutation in ORAI1 (ORAI1-A88SfsX25), and a second patient is compound heterozygous for 2 missense mutations in ORAI1 (ORAI1-A103E/L194P). All 3 mutations abolish ORAI1 expression and impair Ca2+ influx and CRAC channel function. The clinical syndrome associated with ORAI1 deficiency is characterized by immunodeficiency with a defect in the function but not in the development of lymphocytes, congenital myopathy, and anhydrotic ectodermal dysplasia with a defect in dental enamel calcification. In contrast with the limited clinical phenotype, we found ORAI1 protein expression in a wide variety of cell types and organs., Conclusion: Ca2+ influx through ORAI1 is crucial for lymphocyte function in vivo. Despite almost ubiquitous ORAI1 expression, the channel has a nonredundant role in only a few cell types judging from the limited clinical phenotype in ORAI1-deficient patients.

A mutation in ORAI1, the gene encoding the pore-forming subunit of the Ca(2+)-release-activated Ca(2+) (CRAC) channel, abrogates the store-operated entry of Ca(2+) into cells and impairs lymphocyte activation. Stromal interaction molecule 1 (STIM1) in the endoplasmic reticulum activates ORAI1-CRAC channels. We report on three siblings from one kindred with a clinical syndrome of immunodeficiency, hepatosplenomegaly, autoimmune hemolytic anemia, thrombocytopenia, muscular hypotonia, and defective enamel dentition. Two of these patients have a homozygous nonsense mutation in STIM1 that abrogates expression of STIM1 and Ca(2+) influx., (2009 Massachusetts Medical Society)

Defective apoptosis caused by mutations of the Fas gene can lead to an autoimmune lymphoproliferative syndrome (ALPS). The main autoimmune manifestations are haematological: hemolytic anemia, thrombocytopenia and neutropenia. We described 3 patients with ALPS presenting as a lymphoproliferative syndrome associated with a Coomb's negative autoimmune hemolytic anemia and dyserythropoiesis predominating on the more mature erythroblasts. Fas apoptosis deficiency was evidenced in the 3 patients by the demonstration of an increased number of CD4(-)CD8(-)TCRalphabeta(+) T cells, a decreased apoptotic response of activated T lymphocytes to anti-Apo 1-3 monoclonal antibody and the presence of a heterozygous mutation of the Fas receptor gene.

Defective lymphocyte apoptosis caused by mutations of the Fas gene can result in an autoimmune lymphoproliferative syndrome (ALPS) in humans. We report two cases of dyserythropoiesis associated with a Fas-deficient condition in childhood. In both cases, dyserythropoiesis predominated on the more mature erythroblasts, and was associated with a lymphoproliferative syndrome as well as with haemolytic anaemia, hypergammaglobulinaemia and the expansion of an unusual population of CD4- CD8- T cells that express the alpha/beta T-cell receptor. The regression of dyserythropoiesis under steroid therapy suggested that it resulted from an autoimmune mechanism, itself secondary to the lymphocyte Fas apoptosis deficiency. Fas-defective apoptosis may be a new aetiology for childhood dyserythropoiesis.

The authors have studied a series of 23 DiGeorge syndrome patients by prometaphase chromosome analysis and/or by FISH with a set of 6 cosmid probes spanning the previously described commonly deleted region. Four patients display a cytogenetically visible interstitial deletion in band 22q11.2, whereas the other 18 patients exhibit a molecular deletion evidenced only by FISH analysis. For 21 of the patients studied, the deletion encompasses the 6 loci tested, while for one, only the most telomeric of these loci is conserved. The last patient does not show any deletion with the probes used.

Major histocompatibility complex class II deficiency (bare lymphocyte syndrome) is a rare primary immunodeficiency disorder characterized by profound defects in human leukocyte antigen class II expression, inconsistent and incomplete expression of human leukocyte antigen class I molecules, and a complete lack of cellular and humoral immune responses to foreign antigens. To define the clinical and immunologic characteristics, outcome, and natural history of major histocompatibility complex class II deficiency, we retrospectively analyzed 30 consecutive patients. Clinical onset occurred in the first year of life, usually involving recurrent bronchopulmonary infections and chronic diarrhea. The clinical course was complicated by viral meningoencephalitis, hepatitis, cholangitis, and various autoimmune phenomena. Prognosis was very poor: the mean age at the time of death was 4 years. The main cause of death was overwhelming viral infection. Recent advances in bone marrow transplantation have raised hopes of curative treatment: 6 of 14 patients who underwent bone marrow transplantation were cured. Long-term survival after human leukocyte antigen-identical and haploidentical bone marrow transplantation seemed to depend primarily on the presence of preexisting viral infections.

We describe the relative ordering, by fluorescence in situ hybridization, of cosmid loci and translocation breakpoints in the DiGeorge syndrome (DGS) critical region of chromosome 22. This physical map enables us to define a large region, commonly deleted in a majority of affected patients, and the smallest deleted region which, when lost, is sufficient to produce DGS. In four instances, a similar large deleted region is observed in a familial context. In these pedigrees, the deletion is encountered in one parent with mild features of the disease.

A new patient with the rare ICF syndrome (immunodeficiency, centromeric heterochromatin instability, and facial anomalies) is reported. The six patients previously reported in the literature are reviewed. The main clinical and cytogenetic characteristics of the syndrome are discussed.