Primary immune regulatory disorders (PIRD): expanding the mutation spectrum in Turkey and identification of sixteen novel variants.

Human Inborn Errors of Immunity (IEIs) encompass a clinically and genetically heterogeneous group of disorders, ranging from mild cases to severe, life-threatening types. Among these, Primary Immune Regulatory Disorders (PIRDs) constitute a subset of IEIs characterized by diverse clinical phenotypes, prominently featuring severe atopy, autoimmunity, lymphoproliferation, hyperinflammation, autoinflammation, and susceptibility to malignancies. According to the latest report from the International Union of Immunological Societies (IUIS), PIRDs arise from mutations in various genes including LYST, RAB27A, AP3B1, AP3D1, PRF1, UNC13D, STX11, STXBP2, FAAP24, SLC7A7, RASGRP1, CD70, CTPS1, RLTPR, ITK, MAGT1, PRKCD, TNFRSF9, SH2DIA, XIAP, CD27 (TNFRSF7), FAS (TNFRSF6), FASLG (TNFSF6), CASP10, CASP8, FADD, LRBA, STAT3, AIRE, ITCH, ZAP70, TPP2, JAK1, PEPD, FOXP3, IL2RA, CTLA4, BACH2, IL2RB, DEF6, FERMT1, IL10, IL10RA, IL10RB, NFAT5, TGFB1, and RIPK1 genes. We designed a targeted next-generation sequencing (TNGS) workflow using the Ion AmpliSeq™ Primary Immune Deficiency Research Panel to sequence 264 genes associated with IEIs on the Ion S5™ Sequencer. In this study, we report the identification of 38 disease-causing variants, including 16 novel ones, detected in 40 patients across 15 distinct PIRD genes. The application of next-generation sequencing enabled rapid and precise diagnosis of patients with PIRDs.

Autoimmune Cytopenias Are Highly Associated with Inborn Errors of Immunity and They May Be the Initial Presentations in Cases without Severe Infections.

INTRODUCTION: Inborn errors of immunity (IEIs) are inherited disorders that present with increased susceptibility to infections as well as noninfectious complications. Due to the aberrant immune functions of patients with IEI, autoimmune cytopenia (AIC) may be the initial finding, which makes diagnosis a challenge. We aimed to evaluate the clinical course, laboratory findings, and treatment response of AIC in children with IEI. METHODS: Data of children with autoimmune hemolytic anemia (AIHA) and/or immune thrombocytopenic purpura (ITP) were obtained from a retrospective chart review of IEI patients diagnosed and followed in our center. Demographic and clinical features and therapeutic outcomes were evaluated. Immunologic findings were compared between patients with AIHA, ITP, and Evans syndrome (ES). The patients were also divided into two subgroups based on the presence or absence of immune dysregulation diseases (IDDs), and all data were compared between these two groups. RESULTS: Out of 562 patients with IEI, 6% (n: 34) had AIC which were ITP (23.5%), AIHA (35.5%), and ES (41.2%). AIC was the initial finding in 50% of these 34 patients. Patients with ES had a higher mean percentage of CD8+ T lymphocytes than ITP patients (40.77 ± 20.21% vs. 22.33 ± 12.48%, p = 0.011). Patients with IDDs were more likely to develop ES (p = 0.004), lymphoproliferation (p = 0.005), and resistance to first-line therapy (p = 0.021) than other IEI groups. CONCLUSION: This study shows that AIC may be the initial finding of IEI, particularly when lymphoproliferation and resistance to first-line therapy co-occur. Therefore, detailed investigation should be offered to all patients to avoid diagnostic delay.

Therapeutic modalities and clinical outcomes in a large cohort with LRBA deficiency and CTLA4 insufficiency.

BACKGROUND: LPS-responsive beige-like anchor (LRBA) deficiency (LRBA-/-) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA4) insufficiency (CTLA4+/-) are mechanistically overlapped diseases presenting with recurrent infections and autoimmunity. The effectiveness of different treatment regimens remains unknown. OBJECTIVE: Our aim was to determine the comparative efficacy and long-term outcome of therapy with immunosuppressants, CTLA4-immunoglobulin (abatacept), and hematopoietic stem cell transplantation (HSCT) in a single-country multicenter cohort of 98 patients with a 5-year median follow-up. METHODS: The 98 patients (63 LRBA-/- and 35 CTLA4+/-) were followed and evaluated at baseline and every 6 months for clinical manifestations and response to the respective therapies. RESULTS: The LRBA-/- patients exhibited a more severe disease course than did the CTLA4+/- patients, requiring more immunosuppressants, abatacept, and HSCT to control their symptoms. Among the 58 patients who received abatacept as either a primary or rescue therapy, sustained complete control was achieved in 46 (79.3%) without severe side effects. In contrast, most patients who received immunosuppressants as primary therapy (n = 61) showed either partial or no disease control (72.1%), necessitating additional immunosuppressants, abatacept, or transplantation. Patients with partial or no response to abatacept (n = 12) had longer disease activity before abatacept therapy, with higher organ involvement and poorer disease outcomes than those with a complete response. HSCT was performed in 14 LRBA-/- patients; 9 patients (64.2%) showed complete remission, and 3 (21.3%) continued to receive immunosuppressants after transplantation. HSCT and abatacept therapy gave rise to similar probabilities of survival. CONCLUSIONS: Abatacept is superior to immunosuppressants in controlling disease manifestations over the long term, especially when started early, and it may provide a safe and effective therapeutic alternative to transplantation.

Clinical, immunological, molecular and therapeutic findings in monogenic immune dysregulation diseases: Middle East and North Africa registry.

Monogenic immune dysregulation diseases (MIDD) are caused by defective immunotolerance. This study was designed to increase knowledge on the prevalence and spectrum of MIDDs, genetic patterns, and outcomes in Middle East and North Africa (MENA). MIDD patients from 11 MENA countries (Iran, Turkey, Kuwait, Oman, Algeria, Egypt, United Arab Emirates, Tunisia, Jordan, Qatar, and Azerbaijan) were retrospectively evaluated. 343 MIDD patients (58% males and 42% female) at a median (IQR) age of 101 (42-192) months were enrolled. The most common defective genes were LRBA (23.9%), LYST (8.2%), and RAB27A (7.9%). The most prevalent initial and overall manifestations were infections (32.2% and 75.1%), autoimmunity (18.6% and 41%), and organomegaly (13.3% and 53.8%), respectively. Treatments included immunoglobulin replacement therapy (53%), hematopoietic stem cell transplantation (HSCT) (14.3%), immunosuppressives (36.7%), and surgery (3.5%). Twenty-nine (59.2%) patients survived HSCT. Along with infectious complications, autoimmunity and organomegaly may be the initial or predominant manifestations of MIDD.

Comparing the levels of CTLA-4-dependent biological defects in patients with LRBA deficiency and CTLA-4 insufficiency.

BACKGROUND: Lipopolysaccharide-responsive beige-like anchor protein (LRBA) deficiency and cytotoxic T-lymphocyte protein-4 (CTLA-4) insufficiency are recently described disorders that present with susceptibility to infections, autoimmunity, and lymphoproliferation. Clinical and immunological comparisons of the diseases with long-term follow-up have not been previously reported. We sought to compare the clinical and laboratory manifestations of both diseases and investigate the role of flow cytometry in predicting the genetic defect in patients with LRBA deficiency and CTLA-4 insufficiency. METHODS: Patients were evaluated clinically with laboratory assessments for lymphocyte subsets, T follicular helper cells (TFH ), LRBA expression, and expression of CD25, FOXP3, and CTLA4 in regulatory T cells (Tregs) at baseline and 16 h post-stimulation. RESULTS: LRBA-deficient patients (n = 29) showed significantly early age of symptom onset, higher rates of pneumonia, autoimmunity, chronic diarrhea, and failure to thrive compared to CTLA-4 insufficiency (n = 12). In total, 29 patients received abatacept with favorable responses and the overall survival probability was not different between transplanted versus non-transplanted patients in LRBA deficiency. Meanwhile, higher probability of survival was observed in CTLA-4-insufficient patients (p = 0.04). The T-cell subsets showed more deviation to memory cells in CTLA-4-insufficiency, accompanied by low percentages of Treg and dysregulated cTFH cells response in both diseases. Cumulative numbers of autoimmunities positively correlated with cTFH frequencies. Baseline CTLA-4 expression was significantly diminished in LRBA deficiency and CTLA-4 insufficiency, but significant induction in CTLA-4 was observed after short-term T-cell stimulation in LRBA deficiency and controls, while this elevation was less in CTLA-4 insufficiency, allowing to differentiate this disease from LRBA deficiency with high sensitivity (87.5%) and specificity (90%). CONCLUSION: This cohort provided detailed clinical and laboratory comparisons for LRBA deficiency and CTLA-4 insufficiency. The flow cytometric approach is useful in predicting the defective gene; thus, targeted sequencing can be conducted to provide rapid diagnosis and treatment for these diseases impacting the CTLA-4 pathway.

Simple Measurement of IgA Predicts Immunity and Mortality in Ataxia-Telangiectasia.

Patients with ataxia-telangiectasia (A-T) suffer from progressive cerebellar ataxia, immunodeficiency, respiratory failure, and cancer susceptibility. From a clinical point of view, A-T patients with IgA deficiency show more symptoms and may have a poorer prognosis. In this study, we analyzed mortality and immunity data of 659 A-T patients with regard to IgA deficiency collected from the European Society for Immunodeficiencies (ESID) registry and from 66 patients with classical A-T who attended at the Frankfurt Goethe-University between 2012 and 2018. We studied peripheral B- and T-cell subsets and T-cell repertoire of the Frankfurt cohort and survival rates of all A-T patients in the ESID registry. Patients with A-T have significant alterations in their lymphocyte phenotypes. All subsets (CD3, CD4, CD8, CD19, CD4/CD45RA, and CD8/CD45RA) were significantly diminished compared to standard values. Patients with IgA deficiency (n = 35) had significantly lower lymphocyte counts compared to A-T patients without IgA deficiency (n = 31) due to a further decrease of naïve CD4 T-cells, central memory CD4 cells, and regulatory T-cells. Although both patient groups showed affected TCR-ß repertoires compared to controls, no differences could be detected between patients with and without IgA deficiency. Overall survival of patients with IgA deficiency was significantly diminished. For the first time, our data show that patients with IgA deficiency have significantly lower lymphocyte counts and subsets, which are accompanied with reduced survival, compared to A-T patients without IgA deficiency. IgA, a simple surrogate marker, is indicating the poorest prognosis for classical A-T patients. Both non-interventional clinical trials were registered at clinicaltrials.gov 2012 (Susceptibility to infections in ataxia-telangiectasia; NCT02345135) and 2017 (Susceptibility to Infections, tumor risk and liver disease in patients with ataxia-telangiectasia; NCT03357978).

Combined immunodeficiency with marginal zone lymphoma due to a novel homozygous mutation in IL-21R gene and successful treatment with hematopoietic stem cell transplantation.

Mutations in the interleukin-21 receptor (IL-21R) gene are recently defined as primary immunodeficiency diseases. IL-21R defects result in combined immunodeficiency by affecting the functions of innate and adaptive immune system components.A six-year-old girl was admitted to our hospital with complaints of chronic diarrhea that started after the newborn period and generalized rash over the last three months. She had severe respiratory distress due to Cytomegalovirus (CMV) pneumonia requiring mechanical ventilation and was diagnosed as combined immunodeficiency at another hospital at the age of four. Her physical examination on admission revealed erythematous rash on cheeks, extremities, gluteal region, and lymph node enlargements in cervical, axillary, and inguinal regions. CMV DNA and stool Cryptosporidium parvum were positive. Marginal zone lymphoma -negative for Epstein-Bar virus- was reported in the lymph node biopsy. Targeted next-generation sequencing Ion AmpliSeq™ primary immunodeficiency panel revealed a novel homozygous IL21R c.132delC (p.Ser45fs) mutation.This case is presented to emphasize that IL21R defects should be considered in the differential diagnosis of the patients with recurrent respiratory infections, chronic diarrhea, C. parvum infection, chronic liver disease, sclerosing cholangitis, and malignancy where early hematopoietic stem cell transplantation (HSCT) is life-saving. A total of eight cases with IL21R gene defects have been reported so far. The significance of this case is that it is the first case of malignancy among the published IL-21R deficient patients successfully treated with HSCT.

A Novel Homozygous TRNT1 Mutation in a Child With an Early Diagnosis of Common Variable Immunodeficiency Leading to Mild Hypogammaglobulinemia and Hemolytic Anemia.

Although sideroblastic anemias (SAs) may be associated with different etiologies, deterioration of mitochondrial heme biosynthesis in bone marrow erythroid cells is a general abnormality. Congenital SA associated with immunodeficiency, periodic fever, and developmental delay is because of loss-of-function mutations in the TRNT1 gene. We report a patient with a novel homozygous mutation in the TRNT1 gene presenting with anemia with siderocytes, hypogammaglobulinemia, hepatosplenomegaly, and brittle hair but without periodic fever or developmental delay. The patient was presented to emphasize the power of reverse phenotyping in the differential diagnosis of primary immunodeficiency patients with atypical features and to raise awareness for TRNT1 disease in case of coexistent SA and hypogammaglobulinemia.

Recurrent infections, neurologic signs, low serum uric acid levels, and lymphopenia in childhood: Purine nucleoside phosphorylase deficiency, an emergency for infants.

Purine nucleoside phosphorylase deficiency is one of the severe combined immunodeficiencies, which often clinically manifests with recurrent infections, neurologic symptoms and autoimmune diseases, and leads to thymocyte development and peripheral T cell activation defects. It is an immunologic emergency for childhood. In this case series, four cases with purine nucleoside phosphorylase deficiency were evaluated. Recurrent febrile infections and neuromotor developmental retardation were among the presenting symptoms in all cases. Absolute lymphocyte counts and serum uric acid levels were very low, and serum immunoglobulin levels were normal or slightly lower in all cases. The genetic molecular analysis of four patients revealed three predefined mutations in the purine nucleoside phosphorylase gene. Three of the four patients were lost due to sepsis during follow-up, and one patient was lost due to veno-occlusive disease in the post-hematopoietic stem cell transplantation period. We presented these cases to emphasize that purine nucleoside phosphorylase deficiency should always be considered in patients with frequent recurrent infections, neurologic findings, low serum uric acid levels, and lymphopenia.

The evaluation of malignancies in Turkish primary immunodeficiency patients; a multicenter study.

BACKGROUND: There are no data regarding the prevalence of malignancies in patients with primary immunodeficiency (PID) in Turkey. Along with the prevalence of malignancy, we aimed to present the types of malignancy and define the underlying immune deficiency of the patients. METHOD: Between the years 1992 and 2018, from five tertiary immunology clinics, fifty-nine patients with PID who developed malignancy were included. All patients were evaluated for demographics, clinical features, and prognosis. RESULTS: The prevalence of malignancy in our cohort was detected as 0.9% (59/6392). The male-to-female ratio was 1.8 (38/21), and the median age of patients was 14 years (range: 1.5-51). The median age at diagnosis of malignancy was 10 years (range: 1.5-51). Ataxia-telangiectasia was the most frequent PID in patients with malignancy (n = 19, 32.2%), and non-Hodgkin lymphoma was the most common malignancy (n = 32, 51.6%). The rate of malignancy in DOCK8 deficiency (n = 7/43, 16.3%) was higher than AT (n = 19/193, 9.8%), Wiskott-Aldrich syndrome (n = 2/22, 9.1%), and common variable immunodeficiency (n = 11/205, 5.4%). EBV quantitative PCR was positive in 16 out of 53 patients (30.2%). Three patients had secondary malignancies. Remission was achieved in 26 patients (44.1%). However, 31 patients (52.5%) died. Two patients (3.4%) are still on chemotherapy. CONCLUSION: This study is the largest cohort investigating the association of malignancy in patients with PID in Turkey. While lymphoid malignancies were the most common malignancy and observed more frequently in AT patients, the risk for malignancy was higher in patients with DOCK8 deficiency compared to AT.

Long-term outcome of LRBA deficiency in 76 patients after various treatment modalities as evaluated by the immune deficiency and dysregulation activity (IDDA) score.

BACKGROUND: Recent findings strongly support hematopoietic stem cell transplantation (HSCT) in patients with severe presentation of LPS-responsive beige-like anchor protein (LRBA) deficiency, but long-term follow-up and survival data beyond previous patient reports or meta-reviews are scarce for those patients who do not receive a transplant. OBJECTIVE: This international retrospective study was conducted to elucidate the longitudinal clinical course of patients with LRBA deficiency who do and do not receive a transplant. METHOD: We assessed disease burden and treatment responses with a specially developed immune deficiency and dysregulation activity score, reflecting the sum and severity of organ involvement and infections, days of hospitalization, supportive care requirements, and performance indices. RESULTS: Of 76 patients with LRBA deficiency from 29 centers (median follow-up, 10 years; range, 1-52), 24 underwent HSCT from 2005 to 2019. The overall survival rate after HSCT (median follow-up, 20 months) was 70.8% (17 of 24 patients); all deaths were due to nonspecific, early, transplant-related mortality. Currently, 82.7% of patients who did not receive a transplant (43 of 52; age range, 3-69 years) are alive. Of 17 HSCT survivors, 7 are in complete remission and 5 are in good partial remission without treatment (together, 12 of 17 [70.6%]). In contrast, only 5 of 43 patients who did not receive a transplant (11.6%) are without immunosuppression. Immune deficiency and dysregulation activity scores were significantly lower in patients who survived HSCT than in those receiving conventional treatment (P = .005) or in patients who received abatacept or sirolimus as compared with other therapies, and in patients with residual LRBA expression. Higher disease burden, longer duration before HSCT, and lung involvement were associated with poor outcome. CONCLUSION: The lifelong disease activity, implying a need for immunosuppression and risk of malignancy, must be weighed against the risks of HSCT.

Abatacept as a Long-Term Targeted Therapy for LRBA Deficiency.

BACKGROUND: LPS-responsive beige-like anchor (LRBA) deficiency presents with susceptibility to infections, autoimmunity, and lymphoproliferation. The long-term efficacy of cytotoxic T-lymphocyte-associated antigen 4-immunoglobulin (abatacept) as targeted therapy for its immune dysregulatory features remains to be established. OBJECTIVE: To determine the clinical and immunologic features of LRBA deficiency and long-term efficacy of abatacept treatment in controlling the different disease manifestations. METHODS: Twenty-two LRBA-deficient patients were recruited from different immunology centers and followed prospectively. Eighteen patients on abatacept were evaluated every 3 months for long-term clinical and immunologic responses. LRBA expression, lymphocyte subpopulations, and circulating T follicular helper cells were determined by flow cytometry. RESULTS: The mean age of the patients was 13.4 ± 7.9 years, and the follow-up period was 3.4 ± 2.3 years. Recurrent infections (n = 19 [86.4%]), immune dysregulation (n = 18 [81.8%]), and lymphoproliferation (n = 16 [72.7%]) were common clinical features. The long-term benefits of abatacept in 16 patients were demonstrated by complete control of lymphoproliferation and chronic diarrhea followed by immune dysregulation, most notably autoimmune cytopenias. Weekly or every other week administration of abatacept gave better disease control compared with every 4 weeks. There were no serious side effects related to the abatacept therapy. Circulating T follicular helper cell frequencies were found to be a reliable biomarker of disease activity, which decreased on abatacept therapy in most subjects. However, high circulating T follicular helper cell frequencies persisted in 2 patients who had a more severe disease phenotype that was relatively resistant to abatacept therapy. CONCLUSIONS: Long-term abatacept therapy is effective in most patients with LRBA deficiency.

Chronic granulamatous disease: Two decades of experience from a paediatric immunology unit in a country with high rate of consangineous marriages.

Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by susceptibility to bacterial and fungal infections resulting from the inadequacy of phagocytic leucocytes to produce reactive oxygen radicals. CGD is a genetically heterogeneous disease with an X-linked recessive (XR-CGD) form caused by mutations in the CYBB (OMIM #300481) gene encoding the gp91(phox) protein, and an autosomal recessive (AR-CGD) form caused by mutations in the CYBA (OMIM #608508), NCF1 (OMIM #608512), NCF2 (OMIM #608515) and NCF4 (OMIM #601488) genes encoding p22(phox), p47(phox), p67(phox) and p40(phox), respectively. The genetic mutation of one of the cytosolic p47phox/p67phox proteins and membrane-bound gp91phox/p22phox proteins, which constitutes the NADPH oxidase enzyme complex, causes the disease. In this study, we evaluated the clinical, laboratory and genetic findings and the prognostic effects of molecular inheritance of our 24 CGD cases (14 XR, 10 autosomal recessive-AR). Consanguinity (three XR and all AR cases) showed statistically significant relationship with the type of hereditary inheritance (P < 0.001). 83% patients had an infection since early infancy. The mean age of initiation of symptoms was earlier in XR cases, and 78% patients had respiratory tract infections. Bone marrow transplantation was performed in five XR cases (two ex) and four AR (one ex) cases. Three of nine XR and two of six AR cases deceased on medical follow-up. In countries especially with high consanguinity rates, the early diagnosis for appropriate prophylactic treatment of CGD is quietly important to avoid from recurrent severe infections, early death and fatal complications of late transplantation.

Thymic output changes in children with clinical findings signaling a probable primary immunodeficiency.

Karaca N, Azarsiz E, Akarcan SE, Aksu G, Kütükçüler N. Thymic output changes in children with clinical findings signaling a probable primary immunodeficiency. Turk J Pediatr 2019; 61: 885-894. Thymic maturation evaluation is inevitable for patients with clinical and laboratory findings for a primary immunodeficiency, as the T cellimmunodeficiencies are the most severe type. In this study, we aimed to show the usage of T cell surface molecule `CD31` for the evaluation of thymic output in patients (n: 66) with a large spectrum of findings signing a probable primary immunodeficiency. Besides the classical clinical and laboratory approach for these patients, T cell subpopulations as naive, memory, recent thymic emigrant cells were also investigated. The humoral immunodeficiency (34.8%), combined immunodeficiency (34.8%) and cardiopathy (7.6%) were the most frequent diagnosis groups. CD4+CD45RA+ naive T-cells percentages (p: 0.011) and absolute counts (p: 0.004) and absolute CD4+CD45RA+CD31+ RTE (recent thymic emigrant) cell counts (p: 0.007) were significantly lower in combined immunodeficiency group. Naive T-cells (p: 0.037) and RTE cells (p: 0.032) were also lower in patients who had cardiac surgery in the past. In conclusion, flow cytometric CD31+thymic naive RTE cell evaluation may provide rapid clinical information especially on T-cell immune dysfunction and CD4+CD45RA+CD31+ RTE cells may be used as an alternative to TRECs in the diagnosis of combined immunodeficiencies.

An X-Linked Hyper-IgM Patient Followed Successfully for 23 Years without Hematopoietic Stem Cell Transplantation.

When caring for patients with life-limiting diseases, improving survival and optimizing quality of life are the primary goals. For patients with X-linked hyper-IgM syndrome (XHIGM), the treatment modality has to be decided for a particular patient regarding hematopoietic stem cell transplantation or intravenous immunoglobulin replacement therapy with P. jiroveci prophylaxis. A seven-year-old male patient was admitted with recurrent upper and lower respiratory tract infections and recurrent otitis media. His initial immunologic evaluation revealed low IgG and normal IgA and IgM levels with normal lymphocyte phenotyping and inadequate specific antibody responses. He was diagnosed as common variable immunodeficiency and began to receive intravenous immunoglobulin (IVIG) (0.5 gm/kg) with four-week intervals. During follow-up for 23 years under IVIG therapy, he was extremely well and never had severe infections. In 2017, targeted next generation sequencing was performed in order to understand his molecular pathology. A previously described hemizygous c.31C>T(p.Arg11Ter) mutation was found in CD40LG gene. The mother was heterozygous carrier for this mutation and his sister did not have any mutation. Flow cytometric analysis for CD40LG expression on activated T cells showed highly decreased, but not absent, CD40LG expression. In conclusion, diagnostic delay is a clinical problem for patients with CD40LG deficiency, because of low or normal IgM levels, showing that all the hypogammaglobulinemic patients, not only with high serum IgM levels, but also with normal to low IgM levels, have to be examined for CD40LG expression on activated T lymphocytes. Secondly, type of CD40LG mutations leads to enormous interpatient variations regarding serum IgM levels, CD40LG levels on activated T cells, age at diagnosis, severity of clinical findings, and follow-up therapies with or without hematopoietic stem cell therapy.

TNFRSF13B/TACI Alterations in Turkish Patients with Common Variable Immunodeficiency and IgA Deficiency.

BACKGROUND: The Transmembrane Activator and Calcium modulator ligand Interactor (TACI), encoded by TNFRSF13B/TACI gene, is mutated in some patients with Common Variable Immunodeficiency (CVID) and IgA Deficiency (IgAD). The purpose of the study was to investigate for the first time in Turkish patients the prevalence of TNFRSF13B alterations in CVID, selective and partial IgAD patients. METHODS: Forty two CVID, 36 selective IgAD, 34 partial IgAD and 25 healthy controls were included. All patients were examined for TNFRSF13B gene mutations by PCR. RESULTS: The percentages of TNFRSF13B mutations in CVID, selective and partial IgAD patients were 7.1, 2.7 and 2.9%, respectively. No disease causing TNFRSF13B mutation in healthy controls was found. Patients with TACI mutations had recurrent respiratory tract infections. None of them experienced autoimmunity, bronchiectasis or granulomatous disease. In conclusion, TNFRSF13B mutations were present not only in CVID patients, but also in IgAD cases. CONCLUSION: Modifier genes as well as their combination with other genetic or environmental factors may play an important role in the development of the immunodeficiency phenotype.

Gain-of-Function Mutations in STAT1: A Recently Defined Cause for Chronic Mucocutaneous Candidiasis Disease Mimicking Combined Immunodeficiencies.

Chronic Mucocutaneous Candidiasis (CMC) is the chronic, recurrent, noninvasive Candida infections of the skin, mucous membranes, and nails. A 26-month-old girl was admitted with the complaints of recurrent oral Candidiasis, diarrhea, and respiratory infections. Candida albicans grew in oral mucosa swab. CMV and EBV DNA titers were elevated. She had hypergammaglobulinemia; IgE level, percentages of lymphocyte subgroups, and in vitro T-cell proliferation responses were normal. She had parenchymal nodules within the lungs and a calcific nodule in the liver. Chronic-recurrent infections with different pathogens leading to significant morbidity suggested combined immunodeficiency, CMC, or Mendelian susceptibility to mycobacterial diseases. Genetic analysis revealed a predefined heterozygous gain-of-function mutation (GOF) (c.1154 C>T, p.Thr385Met) in the gene coding STAT1 molecule. Hematopoietic stem cell transplantation (HSCT) was planned because of severe recurring infections. Patients with STAT1 GOF mutations may exhibit diverse phenotypes including infectious and noninfectious findings. HSCT should be considered as an early treatment option before permanent organ damage leading to morbidity and mortality develops. This case is presented to prompt clinicians to consider STAT1 GOF mutations in the differential diagnosis of patients with chronic Candidiasis and recurrent infections with multiple organisms, since these mutations are responsible for nearly half of CMC cases reported.

Frequency of Mycobacterium bovis and mycobacteria in primary immunodeficiencies.

AIM: Susceptibility to mycobacterial diseases is observed in some primary immunodeficiency diseases. In this study, we aimed to evaluate mycobacterial infections in primary immunodeficiency diseases. MATERIAL AND METHODS: Patients under follow-up by Ege University Pediatric Immunology Department for severe combined and combined immunodeficiencies, interleukin 12/ interferon gamma receptor deficiency, nuclear factor kappa-beta essential modulator deficiency and chronic granulomatosis disease were evaluated retrospectively in terms of the frequency and characteristics of mycobacterial infections using a questionnaire form for demographic properties, clinical features and laboratory tests. RESULTS: A diagnosis of mycobacterial infection was made clinically in a total of 25 patients including five (11.3%) of 45 patients who had severe combined immune deficiency, 12 (52.3%) of 21 patients who had chronic granulomatous disease, four patients (100%) who had interferon gamma receptor 2 partical deficiency, two patients (100%) who had interleukin 12 receptor beta 1 deficiency and one patient (100%) who had nuclear factor kapa-beta essential modulator deficiency. Mycobacterium strain could be typed in 14 (33%) of these 25 patients including Mycobacterium bovis, Mycobacterium chelonea, Mycobacterium elephantis, Mycobacterium fortuitum, and Mycobacterium tuberculosis. All patients were treated with anti-tuberculosis therapy. Thirty-six percent of these 25 patients underwent hematopoietic stem cell transplantation. Eight patients (five before, three after transplantation) died. CONCLUSIONS: Non-tuberculosis mycobacteria including mainly Mycobacterium bovis were observed with a higher rate compared to Mycobacterium tuberculosis in primary immunodeficiencies, especially in those affecting the interleukin 12/interferon gamma pathway. Early diagnosis of primary immunodeficiencies with neonatal screening program and preventing administration of the Bacille Calmette-Guerin vaccine in these patients is important.

Necrotizing Liver Granuloma/Abscess and Constrictive Aspergillosis Pericarditis with Central Nervous System Involvement: Different Remarkable Phenotypes in Different Chronic Granulomatous Disease Genotypes.

Chronic granulomatous disease (CGD) is a primary immune deficiency causing predisposition to infections with specific microorganisms, Aspergillus species and Staphylococcus aureus being the most common ones. A 16-year-old boy with a mutation in CYBB gene coding gp91phox protein (X-linked disease) developed a liver abscess due to Staphylococcus aureus. In addition to medical therapy, surgical treatment was necessary for the management of the disease. A 30-month-old girl with an autosomal recessive form of chronic granulomatous disease (CYBA gene mutation affecting p22phox protein) had invasive aspergillosis causing pericarditis, pulmonary abscess, and central nervous system involvement. The devastating course of disease regardless of the mutation emphasizes the importance of early diagnosis and intervention of hematopoietic stem cell transplantation as soon as possible in children with CGD.