RASGRP1 deficiency causes immunodeficiency with impaired cytoskeletal dynamics.

RASGRP1 is an important guanine nucleotide exchange factor and activator of the RAS-MAPK pathway following T cell antigen receptor (TCR) signaling. The consequences of RASGRP1 mutations in humans are unknown. In a patient with recurrent bacterial and viral infections, born to healthy consanguineous parents, we used homozygosity mapping and exome sequencing to identify a biallelic stop-gain variant in RASGRP1. This variant segregated perfectly with the disease and has not been reported in genetic databases. RASGRP1 deficiency was associated in T cells and B cells with decreased phosphorylation of the extracellular-signal-regulated serine kinase ERK, which was restored following expression of wild-type RASGRP1. RASGRP1 deficiency also resulted in defective proliferation, activation and motility of T cells and B cells. RASGRP1-deficient natural killer (NK) cells exhibited impaired cytotoxicity with defective granule convergence and actin accumulation. Interaction proteomics identified the dynein light chain DYNLL1 as interacting with RASGRP1, which links RASGRP1 to cytoskeletal dynamics. RASGRP1-deficient cells showed decreased activation of the GTPase RhoA. Treatment with lenalidomide increased RhoA activity and reversed the migration and activation defects of RASGRP1-deficient lymphocytes.

Heterogeneity in RAG1 and RAG2 deficiency: 35 cases from a single-centre.

Recombination activating genes (RAG)1 and RAG2 deficiency leads to combined T/B-cell deficiency with varying clinical presentations. This study aimed to define the clinical/laboratory spectrum of RAG1 and RAG2 deficiency. We retrospectively reviewed the clinical/laboratory data of 35 patients, grouped them as severe combined immunodeficiency (SCID), Omenn syndrome (OS), and delayed-onset combined immunodeficiency (CID) and reported nine novel mutations. The male/female ratio was 23/12. Median age of clinical manifestations was 1 months (mo) (0.5-2), 2 mo (1.25-5), and 14 mo (3.63-27), age at diagnosis was 4 mo (3-6), 4.5 mo (2.5-9.75), and 27 mo (14.5-70) in SCID (n = 25; 71.4%), OS (n = 5; 14.3%), and CID (n = 5; 14.3%) patients, respectively. Common clinical manifestations were recurrent sinopulmonary infections 82.9%, oral moniliasis 62.9%, diarrhea 51.4%, and eczema/dermatitis 42.9%. Autoimmune features were present in 31.4% of the patients; 80% were in CID patients. Lymphopenia was present in 92% of SCID, 80% of OS, and 80% of CID patients. All SCID and CID patients had low T (CD3, CD4, and CD8), low B, and increased NK cell numbers. Twenty-eight patients underwent hematopoietic stem cell transplantation (HSCT), whereas seven patients died before HSCT. Median age at HSCT was 7 mo (4-13.5). Survival differed in groups; maximum in SCID patients who had an HLA-matched family donor, minimum in OS. Totally 19 (54.3%) patients survived. Early molecular genetic studies will give both individualized therapy options, and a survival advantage because of timely diagnosis and treatment. Further improvement in therapeutic outcomes will be possible if clinicians gain time for HSCT.

A single-center study points to diverse features and outcome in patients with Hyperimmunoglobulin M Syndrome and Class- Switch Recombination defects.

Isotype class-switch recombination (CSR), somatic hypermutation (SHM), B cell signalling and DNA repair mechanisms defects are responsible for high IgM. The hyperimmunoglobulin M (HIGM) phenotype and CSR-related defects are now classified under primary antibody defects, combined immunodeficiencies or syndromic immunodeficiencies groups. The aim of the study is to evaluate the diverse phenotypic/genotypic/laboratory characteristics and outcome of patients with CSR defects and HIGM-related defects. We enrolled 50 patients. The most common gene defect was Activation-induced cytidine deaminase (AID) deficiency (n = 18), followed by CD40 Ligand (CD40L) (n = 14) and CD40 (n = 3) deficiency. Median ages at first symptom and diagnosis were significantly lower in CD40L deficiency (8.5 and 30 months, respectively) than AID deficiency (30 and 114 months, respectively) (p = .001 and p = .008, respectively). Frequent clinical symptoms were recurrent (66%) and severe (14.9%) infections, and/or autoimmune/non-infectious inflammatory features (48.4%). Eosinophilia and neutropenia were at a higher rate in CD40L deficiency patients (77.8%, p = .002 and 77.8%, p = .002, respectively) when compared to AID deficiency. Median serum IgM level was low in 28.6% of CD40L deficiency patients. It was significantly lower when compared to AID deficiency (p < 0.001). Six patients (CD40L deficiency n = 4, CD40 deficiency n = 2) underwent hematopoietic stem cell transplantation. Five were alive at the last visit. Four patients two patients with CD40L deficiency, one with CD40 deficiency and one with AID deficiency had novel mutations. In conclusion; patients with CSR defects and HIGM phenotype may present with a wide range of clinical manifestations and laboratory findings. Low IgM, neutropenia and eosinophilia were prominent in patients with CD40L deficiency. Characterization of genetic defect-specific clinical and laboratory features may ease the diagnosis, prevent the underdiagnoses of patients and ameliorate the outcome.

Long Term Follow-Up of the Patients with Severe Combined Immunodeficiency After Hematopoietic Stem Cell Transplantation: A Single-Center Study.

BACKGROUND: We aimed to evaluate hematopoietic stem cell transplantation (HSCT) related outcomes of patients with severe combined immunodeficiency (SCID). METHODS: We retrospectively collected data from SCID patients who were diagnosed, followed up and survived at least 2 years after HSCT. RESULTS: Forty four SCID patients were included in the study. Median age of HSCT and follow-up period after HSCT were 7.1 months and 8.7 years, respectively. Human leukocyte antigen (HLA) identical donors were used in 77.3% (n = 34) of the patients (23 siblings, six fathers, two mothers, three extended family donors), HLA 1-2 mismatched family donors in 11.3% (n = 5), and haploidentical family donors in 11.3% (n = 5). CD3 and CD19 counts were normal in more than 90% and in 45.4% at last follow-up, respectively. Intravenous immunoglobulin (IVIG) could be stopped in 72.7% (n = 32) after HSCT. B+ SCID patients had better CD19 counts than B- (p < .001). T cell numbers, lymphocyte proliferation, IVIG need, immunoglobulin levels, antibody responses did not differ among B- and B+ immunophenotypes. Acute graft-versus-host disease (GVHD) was less in bone marrow transplanted patients (19.4%) than peripheral stem cell (58.3%) transplanted ones (p = .024). There was no correlation between age at transplantation and immune reconstitution. At the last follow-up, 70.2% and 78.3% of the patients had body weight and height above 3rd percentile, respectively. CONCLUSION: The immune reconstitution and the growth were normal in the majority of SCID patients after HSCT. It may be rational to use bone marrow instead of peripheral stem cell, as acute GVHD was less in bone marrow transplanted patients.

Clinical, Laboratory Features and Clinical Courses of Patients with Wiskott Aldrich Syndrome and X-linked Thrombocytopenia-A single center study.

OBJECTIVE: Wiskott Aldrich Syndrome is an X-linked primary immunodeficiency disorder characterized by microthrombocytopenia, severe immunodeficiency, and eczema. To define clinical-laboratory features, genetic defects (known/novel) of 23 patients of Wiskott Aldrich Syndrome/X-linked Thrombocytopenia (WAS/XLT) cohort, establish relationships between molecular defects and clinical features if present, evaluate patients who underwent hematopoietic stem cell transplantation (HSCT) and did not. METHODS: Qualitative analysis from patients' hospital files and Sanger sequencing for molecular diagnosis was performed. Twenty-two WAS patients and one XLT patient were included in the study. RESULTS: The median age of diagnosis was 15 months (2.5-172 months). The most common symptom was otitis media and all patients had microthrombocytopenia. Autoimmune findings were detected in 34.7% (8 patients) of the patients; three patients (13%) had positive anti-nuclear antibody (ANA), three patients (13%) hemolytic anemia, one patient autoimmune neutropenia, two patients vasculitis, and one patient demyelinating polyneuropathy. Nine of the 23 (39,1%) patients had HSCT with nearly 90% success. We identified 13 different mutations in our cohort; seven were novel. CONCLUSIONS: HSCT is the only curative treatment for WAS. The study confirms that early diagnosis is very important for the success of therapy, so we must increase awareness in society and physicians to keep an eye out for clues. Our study cohort and follow-up period are not sufficient to establish phenotype-genotype correlation, so a larger cohort from various centers with longer follow-up will be more decisive.

Genomic Spectrum and Phenotypic Heterogeneity of Human IL-21 Receptor Deficiency.

Biallelic inactivating mutations in IL21R causes a combined immunodeficiency that is often complicated by cryptosporidium infections. While eight IL-21R-deficient patients have been reported previously, the natural course, immune characteristics of disease, and response to hematopoietic stem cell transplantation (HSCT) remain to be comprehensively examined. In our study, we have collected clinical histories of 13 patients with IL-21R deficiency from eight families across seven centers worldwide, including five novel patients identified by exome or NGS panel sequencing. Eight unique mutations in IL21R were identified in these patients, including two novel mutations. Median age at disease onset was 2.5 years (0.5-7 years). The main clinical manifestations were recurrent bacterial (84.6%), fungal (46.2%), and viral (38.5%) infections; cryptosporidiosis-associated cholangitis (46.2%); and asthma (23.1%). Inflammatory skin diseases (15.3%) and recurrent anaphylaxis (7.9%) constitute novel phenotypes of this combined immunodeficiency. Most patients exhibited hypogammaglobulinemia and reduced proportions of memory B cells, circulating T follicular helper cells, MAIT cells and terminally differentiated NK cells. However, IgE levels were elevated in 50% of IL-21R-deficient patients. Overall survival following HSCT (6 patients, mean follow-up 1.8 year) was 33.3%, with pre-existing organ damage constituting a negative prognostic factor. Mortality of non-transplanted patients (n = 7) was 57.1%. Our detailed analysis of the largest cohort of IL-21R-deficient patients to date provides in-depth clinical, immunological and immunophenotypic features of these patients, thereby establishing critical non-redundant functions of IL-21/IL-21R signaling in lymphocyte differentiation, humoral immunity and host defense against infection, and mechanisms of disease pathogenesis due to IL-21R deficiency. Outcome following HSCT depends on prior chronic infections and organ damage, which should thus be considered as early as possible following molecular diagnosis.

Human intracellular ISG15 prevents interferon-α/ß over-amplification and auto-inflammation.

Intracellular ISG15 is an interferon (IFN)-α/ß-inducible ubiquitin-like modifier which can covalently bind other proteins in a process called ISGylation; it is an effector of IFN-α/ß-dependent antiviral immunity in mice. We previously published a study describing humans with inherited ISG15 deficiency but without unusually severe viral diseases. We showed that these patients were prone to mycobacterial disease and that human ISG15 was non-redundant as an extracellular IFN-γ-inducing molecule. We show here that ISG15-deficient patients also display unanticipated cellular, immunological and clinical signs of enhanced IFN-α/ß immunity, reminiscent of the Mendelian autoinflammatory interferonopathies Aicardi-Goutières syndrome and spondyloenchondrodysplasia. We further show that an absence of intracellular ISG15 in the patients' cells prevents the accumulation of USP18, a potent negative regulator of IFN-α/ß signalling, resulting in the enhancement and amplification of IFN-α/ß responses. Human ISG15, therefore, is not only redundant for antiviral immunity, but is a key negative regulator of IFN-α/ß immunity. In humans, intracellular ISG15 is IFN-α/ß-inducible not to serve as a substrate for ISGylation-dependent antiviral immunity, but to ensure USP18-dependent regulation of IFN-α/ß and prevention of IFN-α/ß-dependent autoinflammation.

A Spectrum of Clinical Findings from ALPS to CVID: Several Novel LRBA Defects.

INTRODUCTION: Autosomal recessively inherited lipopolysaccharide-responsive beige-like anchor (LRBA) protein deficiency was shown to be responsible for different types of inborn errors of immunity, such as common variable immunodeficiency (CVID) and autoimmune lymphoproliferative syndrome (ALPS). The aim of this study was to compare patients with LRBA-related ALPS and LRBA-related CVID, to describe their clinical and laboratory phenotypes, and to prepare an algorithm for their diagnosis and management. METHODS: Fifteen LRBA-deficient patients were identified among 31 CVID and 14 possible ALPS patients with Western blotting (WB), primary immunodeficiency disease (PIDD) gene, next-generation panel screening (NGS), and whole exome sequencing (WES). RESULTS: The median age on admission and age of diagnosis were 7 years (0.3-16.5) and 11 years (5-44), respectively. Splenomegaly was seen in 93.3% (14/15) of the patients on admission. Splenectomy was performed to 1/5. Recurrent upper respiratory tract infections (93.3% (14/15)), autoimmune cytopenia (80% (12/15)), chronic diarrhea (53.3% (8/15)), lower respiratory tract infections (53.3% (8/15)), lymphoma (26.6% (4/15)), Evans syndrome (26.6% (4/15)), and autoimmune thyroiditis (20% (3/15)) were common clinical findings and diseases. Lymphopenia (5/15), intermittant neutropenia (4/15), eosinophilia (4/15), and progressive hypogammaglobulinemia are recorded in given number of patients. Double negative T cells (TCRαß+CD4-CD8-) were increased in 80% (8/10) of the patients. B cell percentage/numbers were low in 60% (9/15) of the patients on admission. Decreased switched memory B cells, decreased naive and recent thymic emigrant (RTE) Thelper (Th) cells, markedly increased effector memory/effector memory RA+ (TEMRA) Th were documented. Large PD1+ population, increased memory, and enlarged follicular helper T cell population in the CD4+ T cell compartment was seen in one of the patients. Most of the deleterious missense mutations were located in the DUF1088 and BEACH domains. Interestingly, one of the two siblings with the same homozygous LRBA defect did not have any clinical symptom. Hematopoietic stem cell transplantation (HSCT) was performed to 7/15 (46.6%) of the patients. Transplanted patients are alive and well after a median of 2 years (1-3). In total, one patient died from sepsis during adulthood before HSCT. CONCLUSION: Patients with LRBA deficiency may initially be diagnosed as CVID or ALPS in the clinical practice. Progressive decrease in B cells as well as IgG in ALPS-like patients and addition of IBD symptoms in the follow-up should raise the suspicion for LRBA deficiency. Decreased switched memory B cells, decreased naive and recent thymic emigrant (RTE) Th cells, and markedly increased effector memory/effector memory RA+ Th cells (TEMRA Th) cells are important for the diagnosis of the patients in addition to clinical features. Analysis of protein by either WB or flow cytometry is required when the clinicians come across especially with missense LRBA variants of uncertain significance. High rate of malignancy shows the regulatory T cell's important role of immune surveillance. HSCT is curative and succesful in patients with HLA-matched family donor.

Inherited and acquired immunodeficiencies underlying tuberculosis in childhood.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (M.tb) and a few related mycobacteria, is a devastating disease, killing more than a million individuals per year worldwide. However, its pathogenesis remains largely elusive, as only a small proportion of infected individuals develop clinical disease either during primary infection or during reactivation from latency or secondary infection. Subacute, hematogenous, and extrapulmonary disease tends to be more frequent in infants, children, and teenagers than in adults. Life-threatening primary TB of childhood can result from known acquired or inherited immunodeficiencies, although the vast majority of cases remain unexplained. We review here the conditions conferring a predisposition to childhood clinical diseases caused by mycobacteria, including not only M.tb but also weakly virulent mycobacteria, such as BCG vaccines and environmental mycobacteria. Infections with weakly virulent mycobacteria are much rarer than TB, but the inherited and acquired immunodeficiencies underlying these infections are much better known. Their study has also provided genetic and immunological insights into childhood TB, as illustrated by the discovery of single-gene inborn errors of IFN-γ immunity underlying severe cases of TB. Novel findings are expected from ongoing and future human genetic studies of childhood TB in countries that combine a high proportion of consanguineous marriages, a high incidence of TB, and an excellent clinical care, such as Iran, Morocco, and Turkey.

ADA Deficiency: Evaluation of the Clinical and Laboratory Features and the Outcome.

INTRODUCTION: Adenosine deaminase (ADA) deficiency is an autosomal recessive primary immunodeficiency. It results in the intracellular accumulation of toxic metabolites which have effects particularly on lymphocytes and the brain. The aim of this study was to evaluate the outcome of 13 ADA-deficient patients. We planned to evaluate their clinical and laboratory findings before and after enzyme replacement therapy (ERT), allogeneic hematopoietic stem cell transplantation (aHSCT), and hematopoietic stem cell gene therapy (HSCGT). METHODS: Measurement of ADA enzyme activity and metabolites and sequencing of the ADA gene were performed in most of the patients with ADA deficiency. One of the patients with late-onset ADA deficiency was diagnosed by the help of primary immunodeficiency panel screening. RESULTS: Ten out of 13 patients were diagnosed as SCID, while 3 out of 13 were diagnosed as delayed-/late-onset ADA deficiency. Late-onset ADA deficiency patients had clinical and laboratory findings of combined immunodeficiency (CID). Eight patients with ADA-SCID were found to have higher levels of ADA metabolite (dAXP%) (62.1% (34.6-71.9)) than 3 patients with delayed-/late-onset ADA deficiency (6.9% (2.1-8.9). All but one patient with SCID had T-B-NK- phenotype, one had T-B-NK+ phenotype. Genetic defect was documented in 11 patients. Four out of 11 patients had compound heterozygous defects. Three out of 4 patients with compound heterozygous defects had delayed-onset/late-onset ADA deficiency. Seven out of 11 patients with SCID had homozygous defects. Five out of 7 had the same homozygous indel frameshift mutation (c.955-959delGAAGA) showing a founder effect. There were two novel splice site defects: one (IVS10+2T>C) was heterozygous in a patient with late-onset ADA deficiency, and the other was homozygous (IVS2delT+2) in a SCID patient. Other defects were missense defects. Nine out of 13 patients were put on pegylated ADA ERT. Four out of six patients were transplanted without using a conditioning regimen. HSCGT was performed to one of the patients. CONCLUSION: The genetic diagnosis of SCID is utmost important. There is a chance to give ERT before the definitive therapy if the patient with SCID/CID has ADA deficiency. Although ERT was insufficient to restore a normal immune function in ADA-SCID patients, it was useful to improve and stabilize the clinical status before curative therapy (aHSCT/HSCGT). Enzyme replacement therapy was successful in patients with late-/delayed-onset ADA deficiency who presented with the features of combined immunodeficiency. Gastrointestinal polyposis in a patient with late-onset ADA deficiency may be an association or a coincidental finding. Intermittent neurodevelopmental evaluation especially for hearing impairment should be performed in most of the ADA-deficient patients. This may alleviate the speech delay and cognitive abnormalities which may be observed in the follow-up.

B lymphocyte subsets and outcomes in patients with an initial diagnosis of transient hypogammaglobulinemia of infancy.

PURPOSE: Transient hypogammaglobulinemia of infancy (THI) is a common immunodeficiency, but definitive diagnosis can only be made retrospectively. While the pathogenesis is still unknown, abnormalities have been reported in the B cell compartment. In this study, we analysed the B cell subsets of patients with an initial THI diagnosis (n = 20) and compared them with those of healthy age-matched Turkish children (n = 72). METHODS: Flow cytometric analyses of the B subsets were performed by staining with anti-CD27-PE, anti-CD19-PerCP, anti-IgD-FITC and anti-IgM-APC antibodies. RESULTS: During a median follow-up of 6.6 years, 13 patients whose IgG levels had normalized before they reached four years of age were diagnosed with definitive THI. The memory subsets of these patients were lower but not statistically different from the healthy controls (HC). The remaining seven patients had prolonged hypogammaglobulinemia after the age of four and had significantly lower memory B cell subsets compared to the HC. On follow-up, these patients had not experienced recurrent infections or autoimmunity. Re-evaluation of patients' B cell subsets six years later showed that the memory B cell ratios had increased to levels comparable to HC, despite the patients still having mildly low IgG levels. CONCLUSION: Patients with prolonged hypogammaglobulinemia had lower levels of memory B cells despite having a similar clinical course to patients who had been diagnosed with definitive THI. This subgroup of putative THI patients poses a diagnostic and classification dilemma. Our results suggested that these patients' memory B cells and IgG levels may recover over time.

A novel mutation in TAP1 gene leading to MHC class I deficiency: Report of two cases and review of the literature.

Major histocompatibility complex (MHC) class I deficiency syndrome is a rare primary immunodeficiency caused by mutations in the peptide transporter complex associated with antigen presentation (TAP) gene which plays a crucial role in intracellular peptide antigen presentation. A few cases have been reported to date. Recurrent sinopulmonary infections and skin ulcers are the main characteristics of the syndrome. Here we report two siblings diagnosed with TAP1 deficiency syndrome associated only with recurrent sinopulmonary infections with the description of a novel mutation leading to a premature stop codon in TAP1 gene and review of the relevant literature. Both of the siblings had recurrent sinopulmonary infections since childhood, responded to antibiotherapy well, neither of them had hospitalization history because of infections. One had chronic hepatitis B infection which may possibly be related to TAP1 gene defect.

Recurrent viral infections associated with a homozygous CORO1A mutation that disrupts oligomerization and cytoskeletal association.

BACKGROUND: Coronin-1A (CORO1A) is a regulator of actin dynamics important for T-cell homeostasis. CORO1A deficiency causes T(-)B(+) natural killer-positive severe combined immunodeficiency or T-cell lymphopenia with severe viral infections. However, because all known human mutations in CORO1A abrogate protein expression, the role of the protein's functional domains in host immunity is unknown. OBJECTIVE: We sought to identify the cause of the primary immunodeficiency in 2 young adult siblings with a history of disseminated varicella, cutaneous warts, and CD4(+) T-cell lymphopenia. METHODS: We performed immunologic, genetic, and biochemical studies in the patients, family members, and healthy control subjects. RESULTS: Both patients had CD4(+) T-cell lymphopenia and decreased lymphocyte proliferation to mitogens. IgG, IgM, IgA, and specific antibody responses were normal. Whole-genome sequencing identified a homozygous frameshift mutation in CORO1A disrupting the last 2 C-terminal domains by replacing 61 amino acids with a novel 91-amino-acid sequence. The CORO1A(S401fs) mutant was expressed in the patients' lymphocytes at a level comparable with that of wild-type CORO1A in normal lymphocytes but did not oligomerize and had impaired cytoskeletal association. CORO1A(S401fs) was associated with increased filamentous actin accumulation in T cells, severely defective thymic output, and impaired T-cell survival but normal calcium flux and cytotoxicity, demonstrating the importance of CORO1A oligomerization and subcellular localization in T-cell homeostasis. CONCLUSIONS: We describe a truncating mutation in CORO1A that permits protein expression and survival into young adulthood. Our studies demonstrate the importance of intact CORO1A C-terminal domains in thymic egress and T-cell survival, as well as in defense against viral pathogens.

The extended clinical phenotype of 64 patients with dedicator of cytokinesis 8 deficiency.

BACKGROUND: Mutations in dedicator of cytokinesis 8 (DOCK8) cause a combined immunodeficiency (CID) also classified as autosomal recessive (AR) hyper-IgE syndrome (HIES). Recognizing patients with CID/HIES is of clinical importance because of the difference in prognosis and management. OBJECTIVES: We sought to define the clinical features that distinguish DOCK8 deficiency from other forms of HIES and CIDs, study the mutational spectrum of DOCK8 deficiency, and report on the frequency of specific clinical findings. METHODS: Eighty-two patients from 60 families with CID and the phenotype of AR-HIES with (64 patients) and without (18 patients) DOCK8 mutations were studied. Support vector machines were used to compare clinical data from 35 patients with DOCK8 deficiency with those from 10 patients with AR-HIES without a DOCK8 mutation and 64 patients with signal transducer and activator of transcription 3 (STAT3) mutations. RESULTS: DOCK8-deficient patients had median IgE levels of 5201 IU, high eosinophil levels of usually at least 800/µL (92% of patients), and low IgM levels (62%). About 20% of patients were lymphopenic, mainly because of low CD4(+) and CD8(+) T-cell counts. Fewer than half of the patients tested produced normal specific antibody responses to recall antigens. Bacterial (84%), viral (78%), and fungal (70%) infections were frequently observed. Skin abscesses (60%) and allergies (73%) were common clinical problems. In contrast to STAT3 deficiency, there were few pneumatoceles, bone fractures, and teething problems. Mortality was high (34%). A combination of 5 clinical features was helpful in distinguishing patients with DOCK8 mutations from those with STAT3 mutations. CONCLUSIONS: DOCK8 deficiency is likely in patients with severe viral infections, allergies, and/or low IgM levels who have a diagnosis of HIES plus hypereosinophilia and upper respiratory tract infections in the absence of parenchymal lung abnormalities, retained primary teeth, and minimal trauma fractures.

STK4 (MST1) deficiency in two siblings with autoimmune cytopenias: A novel mutation.

Combined immunodeficiencies (CIDs) are heterogeneous group of disorders characterized by abrogated/impaired T cell development and/or functions that resulted from diverse genetic defects. In addition to the susceptibility to infections with various microorganisms, the patients may have lymphoproliferation, autoimmunity, inflammation, allergy and malignancy. Recently, three groups have independently reported patients having mutations in STK4 gene that cause a novel autosomal recessive (AR) CID. We describe here two siblings with a novel STK4 mutation identified during the evaluation of a group of patients with features highly overlapping with those of DOCK-8 deficiency, a form of AR hyperimmunoglobulin E syndrome. The patients' clinical features include autoimmune cytopenias, viral skin (molluscum contagiosum and perioral herpetic infection) and bacterial infections, mild onychomycosis, mild atopic and seborrheic dermatitis, lymphopenia (particularly CD4 lymphopenia), and intermittent mild neutropenia. Determination of the underlying defect and reporting the patients are required for the description of the phenotypic spectrum of each immunodeficiency.

DOCK8 deficiency: clinical and immunological phenotype and treatment options - a review of 136 patients.

Mutations in DOCK8 result in autosomal recessive Hyper-IgE syndrome with combined immunodeficiency (CID). However, the natural course of disease, long-term prognosis, and optimal therapeutic management have not yet been clearly defined. In an international retrospective survey of patients with DOCK8 mutations, focused on clinical presentation and therapeutic measures, a total of 136 patients with a median follow-up of 11.3 years (1.3-47.7) spanning 1693 patient years, were enrolled. Eczema, recurrent respiratory tract infections, allergies, abscesses, viral infections and mucocutaneous candidiasis were the most frequent clinical manifestations. Overall survival probability in this cohort [censored for hematopoietic stem cell transplantation (HSCT)] was 87 % at 10, 47 % at 20, and 33 % at 30 years of age, respectively. Event free survival was 44, 18 and 4 % at the same time points if events were defined as death, life-threatening infections, malignancy or cerebral complications such as CNS vasculitis or stroke. Malignancy was diagnosed in 23/136 (17 %) patients (11 hematological and 9 epithelial cancers, 5 other malignancies) at a median age of 12 years. Eight of these patients died from cancer. Severe, life-threatening infections were observed in 79/136 (58 %); severe non-infectious cerebral events occurred in 14/136 (10 %). Therapeutic measures included antiviral and antibacterial prophylaxis, immunoglobulin replacement and HSCT. This study provides a comprehensive evaluation of the clinical phenotype of DOCK8 deficiency in the largest cohort reported so far and demonstrates the severity of the disease with relatively poor prognosis. Early HSCT should be strongly considered as a potential curative measure.

Clinical features of Candidiasis in patients with inherited interleukin 12 receptor ß1 deficiency.

BACKGROUND: Interleukin 12Rß1 (IL-12Rß1)-deficient patients are prone to clinical disease caused by mycobacteria, Salmonella, and other intramacrophagic pathogens, probably because of impaired interleukin 12-dependent interferon γ production. About 25% of patients also display mucocutaneous candidiasis, probably owing to impaired interleukin 23-dependent interleukin 17 immunity. The clinical features and outcome of candidiasis in these patients have not been described before, to our knowledge. We report here the clinical signs of candidiasis in 35 patients with IL-12Rß1 deficiency. RESULTS: Most (n = 71) of the 76 episodes of candidiasis were mucocutaneous. Isolated oropharyngeal candidiasis (OPC) was the most common presentation (59 episodes, 34 patients) and was recurrent or persistent in 26 patients. Esophageal candidiasis (n = 7) was associated with proven OPC in 2 episodes, and cutaneous candidiasis (n = 2) with OPC in 1 patient, whereas isolated vulvovaginal candidiasis (VVC; n = 3) was not. Five episodes of proven invasive candidiasis were documented in 4 patients; 1 of these episodes was community acquired in the absence of any other comorbid condition. The first episode of candidiasis occurred earlier in life (median age±standard deviation, 1.5 ± 7.87 years) than infections with environmental mycobacteria (4.29 ± 11.9 years), Mycobacterium tuberculosis (4 ± 3.12 years), or Salmonella species (4.58 ± 4.17 years) or other rare infections (3 ± 11.67 years). Candidiasis was the first documented infection in 19 of the 35 patients, despite the vaccination of 10 of these 19 patients with live bacille Calmette-Guérin. CONCLUSIONS: Patients who are deficient in IL-12Rß1 may have candidiasis, usually mucocutaneous, which is frequently recurrent or persistent. Candidiasis may be the first clinical manifestation in these patients.

A novel mutation in leukocyte adhesion deficiency type II/CDGIIc.

Leukocyte adhesion deficiencies (LAD) are autosomal recessive immunodeficiency syndromes characterized by severe and recurrent bacterial infections, impaired wound healing and leukocytosis. Block in different steps in the leukocyte adhesion cascade causes different types of leukocyte adhesion deficiencies, LAD type I, II and III. In LAD type II, the rolling phase of the leukocyte adhesion cascade is affected due to mutations in the specific fucose transporter GFTP (GDP fucose transporter), causing defect in the biosynthesis of selectin ligands on leukocytes. Thus this syndrome is also called congenital disorder of glycosylation IIc (CGDIIc). LAD II/CGDIIc is very rare and has been diagnosed in nine children to date. Fever, leukocytosis, typical dysmorphic features, growth, psychomotor retardation and the Bombay blood group, are characteristic findings in patients. Here, we describe two Turkish siblings with a novel mutation in GFTP. They both have the characteristic features of the syndrome. The older sibling died of severe bacterial pneumonia at the age of 3 years. The younger sibling, diagnosed at the age of 3 months, responded to high dose oral fucose supplementation. Secundum atrial septal defect which was not described in previously reported patients, but present in both of our patients, may primarily related to the defect in fucosylation.

Progressive neurodegenerative syndrome in a patient with X-linked agammaglobulinemia receiving intravenous immunoglobulin therapy.

A progressive encephalopathy of unknown etiology has been described in patients with primary immunodeficiency disorders. In this report, we characterize the clinical features of this progressive neurodegenerative dementing disorder in a young man with Bruton agammaglobulinemia, through neuropsychological tests and a video sequence. The clinical course of the encephalopathy seems rather uniform: Cognition, especially frontal lobe function, is affected in the early stages, and some patients develop movement disorders. The syndrome causes severe cognitive and physical disability, and can eventually be fatal. The autoimmunity results from dysregulated immune responses, but the underlying mechanism has not yet been fully explained.

Clinical, functional, and genetic characterization of chronic granulomatous disease in 89 Turkish patients.

BACKGROUND: Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disorder of phagocytes resulting in impaired killing of bacteria and fungi. A mutation in one of the 4 genes encoding the components p22(phox), p47(phox), p67(phox), and p40(phox) of the leukocyte nicotinamide dinucleotide phosphate reduced (NADPH) oxidase leads to autosomal recessive (AR) CGD. A mutation in the CYBB gene encoding gp91(phox) leads to X-linked recessive CGD. OBJECTIVE: The aim of this study is to show the correlation between clinical, functional, and genetic data of patients with CGD from Turkey. METHODS: We report here the results of 89 patients with CGD from 73 Turkish families in a multicenter study. RESULTS: Most of the families (55%) have an AR genotype, and 38% have an X-linked genotype; patients from 5 families with a suspected AR genotype (7%) were not fully characterized. We compared patients with CGD according to the severity of NADPH oxidase deficiency of neutrophils. Patients with A22(0), A67(0) or X91(0) phenotypes with a stimulation index of 1.5 or less have early clinical presentation and younger age at diagnosis (mean, 3.2 years). However, in p47(phox)-deficient cases and in 5 other AR cases with high residual oxidase activity (stimulation index ≥ 3), later and less severe clinical presentation and older age at diagnosis (mean, 7.1 years) were found. Pulmonary involvement was the most common clinical feature, followed by lymphadenitis and abscesses. CONCLUSION: Later and less severe clinical presentation and older age at diagnosis are related to the residual NADPH oxidase activity of neutrophils and not to the mode of inheritance. CGD caused by A22(0) and A67(0) subtypes manifests as severe as the X91(0) subtype.