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.

Successful management of delayed-onset adenosine deaminase deficiency with novel mutation.

A 4-year-old boy presented with acute-onset autoimmune cytopenia with severe, persistent lymphopenia, autoimmune thyroiditis, elevated IgE and glucose 6-phosphate dehydrogenase enzyme deficiency. In immunologic evaluation, lower T, B and natural killer cells and higher levels of adenosine deaminase (ADA) metabolites were observed. The compound heterozygous novel ADA gene mutations causing ADA deficiency were detected. Successful immunologic and metabolic cure was achieved with enzyme replacement therapy, followed by reduced intensity conditioning hematopoietic stem cell transplantation from a matched unrelated donor. An interesting aspect of this patient is the detection of novel compound heterozygous mutations without consanguinity and a secondary outcome is the recovery of glucose 6-phosphate dehydrogenase deficiency after hematopoietic stem cell transplantation.

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.

Prevalence of Viruses in Acute Asthma Exacerbations in Childhood in a Hospital in West Part of Turkey.

Acute asthma exacerbations (AAE) are episodes characterized by potentially life-threatening and rapidly deteriorating asthma symptoms. Viral respiratory infections are one of the major triggers in the pathophysiology of childhood asthma exacerbations. In this study, we aimed to determine the distribution of viral agents among pediatric AAE patients. One hundred and three AAE patients, aged 5 or older, hospitalized between from February 2017 through February 2020 at Pediatric Immunology and Allergic Diseases Unit were included in this study. Fifty patients (48.5%) were female, and the mean age of the patients was 108.2 months. Viruses were detected in 58 (%56.3) of the patients, in 5 of whom more than one virus type was detected. The most commonly detected virus was human rhinovirus (n=43, 67.1%). Other types included respiratory syncytial virus (n=8; 12.5%), influenza (n=6; 9.3%), human metapneumovirus (n=4; 6.2%), adenovirus (n=1; 1.5%), enterovirus (n=1; 1.5%), and parainfluenza (n=1; 1.5%). Viral agents were detected in 29 out of the 47 patients with allergic asthma, with human rhinoviruses comprising the majority (18 patients). The mean length of hospital stay was 7.89 days. Human rhinovirus is the most common virus that triggers AAE, with similar distributions in allergic and non-allergic asthma. We found no correlation between virus type and the length of hospital stay.

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.

Children with chronic-refractory autoimmune cytopenias: a single center experience.

BACKGROUND AND OBJECTIVES: Autoimmune cytopenias are a group of heterogeneous disorders characterized by immune-mediated destruction of one or more hematopoietic lineage cells. The differential diagnosis of children with autoimmune cytopenias requires much time and laboratory investigations. The aim of the present study was to evaluate the clinical course and significance of autoimmune cytopenias due to immunodeficiency or autoimmune diseases in children at a single children`s hospital. METHOD: Between February 1997 and September 2015, chronic/refractory autoimmune cytopenias patient data were evaluated retrospectively. Twenty-three patients were assessed in this study. RESULTS: The median duration of following was 2.6 years (4 months-18.5 years). The median age of diagnosis was 3.1 years (6 months-16 years). A total of 13 patients (56.5%) had single-lineage and 10 (46.5%) had multilineage cytopenias. The most frequent single-lineage cytopenia was thrombocytopenia, followed by anemia. In 22 of the patients, cytopenias was detected before the primary diseases. All of the patients were treated with corticosteroids or intravenous immune globulin as first-line treatment. Ten patients (43.5%) needed second or further-line immunosuppressive therapies that patients diagnosed as systemic lupus erythematosus, hypogammaglobulinemia, or common variable immunodeficiency. A total of 8 patients (34.7%) recovered from autoimmune cytopenias after the treatment of primer disease. Cytopenias were continued in 14 patients. CONCLUSION: Cytopenia may be the first finding of an immunodeficiency or autoimmune disease and primary disease may be diagnosed in the clinical course. Taking the new targeted treatment options into consideration; early diagnosis is likely to become more important in the near-future in order to begin the treatment for the underlying disease as early as possible.

Long-term effectiveness and safety of canakinumab in pediatric familial Mediterranean fever patients.

Background: Little is known about the long-term efficacy and safety of canakinumab in paediatric FMF patients.Aim: To present the single centre experience of colchicine-resistant paediatric-onset FMF patients who were treated with canakinumab by off-label use since 2012.Methods: The hospital files of 15 children who used canakinumab were retrospectively evaluated. Clinical and laboratory data of each visit were recorded. Drug-related adverse events were recorded. Complete remission was described as no attacks and normal acute phase reactants; partial remission was defined as decrease in severity and rate of attacks and/or elevated acute phase reactants with anti-IL-1 treatment.Results: The average duration of canakinumab use was 23.9 months (min:12, max:58 months). Twelve patients were M694V homozygotes. Eleven patients achieved complete remission after the first dose at 2 months and 12 patients at 6 months. Canakinumab interval was shortened in 2 patients from 150 mg/8 weeks to 150 mg/4 weeks. Except one, 14 patients achieved complete remission by 12 months. Two patients had mild urinary tract infections. One patient had bronchopneumonia requiring hospitalization. Two patients had teeth abscess. There were no serious adverse events such as opportunistic infections, malignancies, or deaths. Besides, no significant laboratory abnormalities occurred in complete blood count parameters, liver and kidney function tests.Conclusion: To the best of our knowledge, this is the longest outcome study about canakinumab use in paediatric FMF patients. This study suggested that canakinumab is safe and effective in children with FMF in the long term.

Characteristics of the patients followed with the diagnosis of common variable immunodeficiency and the complications.

INTRODUCTION: In this study, we aimed to retrospectively evaluate the clinical and laboratory findings and complications of 28 common variable immunodeficiency (CVID) patients. MATERIAL AND METHODS: The clinical features and laboratory data of 28 CVID patients were evaluated. RESULTS: Nineteen patients were male. In 53.5% of the cases, complications included inflammatory bowel disease, cytopenia, bronchiectasis, granulomatous lymphocytic interstitial lung disease (ILD) and asthma. In their immunological evaluations, IgG, IgM, and IgA mean values were 474.8 ±214.1 mg/dl; 56.7 ±41.9 mg/dl; 35.3 ±58.2 mg/dl, respectively, and the vaccine response was positive in 64.2% of the cases. In all age groups, absolute lymphocyte counts, naive (CD19+IgD+27-), nonswitch (CD19+IgD-27+) memory B cells were numerically higher when compared to the data of healthy children; however, although switch memory (CD19+IgD+27+) B cells were proportionally low in the 4-8 and 12-18 age groups, they were low both numerically and proportionally in the 8-12 age group. No statistically significant difference was found between the cases with complications and without complications. But the cases with pulmonary complications were compared within the group, the CD8 ratio was high but the IgA level was low in patients with bronchiectasis and CD3 was numerically and proportionally low in the cases with ILD compared to others. According to the Paris classification, 11/27 (40.7%) of the cases, 3/27 (11.1%) of them and 13/27 (48.2%) of them were evaluated as MB0, MB1, and MB2, respectively. CONCLUSIONS: In genetic studies, TACI (trans-membrane activator and calcium-modulating cyclophilin ligand interactor - TNFRSF13B) mutation was found positive in 25% of the cases.

CD137 deficiency causes immune dysregulation with predisposition to lymphomagenesis.

Dysregulated immune responses are essential underlying causes of a plethora of pathologies including cancer, autoimmunity, and immunodeficiency. We here investigated 4 patients from unrelated families presenting with immunodeficiency, autoimmunity, and malignancy. We identified 4 distinct homozygous mutations in TNFRSF9 encoding the tumor necrosis factor receptor superfamily member CD137/4-1BB, leading to reduced, or loss of, protein expression. Lymphocytic responses crucial for immune surveillance, including activation, proliferation, and differentiation, were impaired. Genetic reconstitution of CD137 reversed these defects. CD137 deficiency is a novel inborn error of human immunity characterized by lymphocytic defects with early-onset Epstein-Barr virus (EBV)-associated lymphoma. Our findings elucidate a functional role and relevance of CD137 in human immune homeostasis and antitumor responses.

The Significance of B-cell Subsets in Patients with Unclassified Hypogammaglobulinemia and Association with Intravenous Immunoglobulin Replacement Requirement.

BACKGROUND: Patients with unclassified hypogammaglobulinemia (UCH) constitute a diagnostic and therapeutic dilemma, because information concerning the clinical and immunological characteristics of these patients is insufficient. OBJECTIVE: To evaluate B-cell subsets in cases with UCH and common variable immunodeficiency (CVID) and their association with treatment requirement in UCH patients. METHODS: The study included 41 UCH, 25 CVID, and 36 healthy individuals between the ages of 4-18 years. RESULTS: The absolute count of total memory and switched memory B-cells were lower in the CVID cases in comparison to the control group. Additionally, the absolute count of marginal zone-like B cells in the 4-10 year age group, and the absolute count of switched plasmablasts in the 10-18 year age group were lower in CVID cases when compared to both the control and UCH groups. The UCH group was categorized based on IVIG replacement therapy. Therefore, the percentage of switched memory B cells was significantly lower in the IVIG-receiving group (10.6% ± 3.10%) compared to the control group (14.0% ± 5.60%). However, there was no significant difference between the IVIG-receiving group and the CVID group. Regarding the comparison of the non-IVIG replacement group and the CVID group, the absolute count of total memory B cells, marginal zone-like B cells, and switched memory B cells were significantly higher in the UCH group. CONCLUSION: B-lymphocyte subsets in UCH cases that did not require IVIG replacement were similar to the control group. On the other hand, the percentage of switched memory B-cells in the UCH cases that required IVIG replacement was not different from that of the CVID cases.

Tuberculosis masked by immunodeficiency: a review of two cases diagnosed with chronic granulomatous disease.

Chronic granulomatous disease (CGD) is a genetically heterogeneous primary immunodeficiency that is characterized by recurrent and life-threatening infections resulting from defects in phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system and granuloma formation due to increased inflammatory response. The most commonly involved organs are the lungs, skin, lymph nodes, and liver due to infection. It may present with recurrent pneumonia, hilar lymphadenopathy, empyema, abscess, reticulonodular patterns, and granulomas due to lung involvement. In recent years, mycobacterial disease susceptibility has been reported in CGD cases. This article presents two male cases, one of whom is aged 18 months and the other is aged 5 years, who were diagnosed with CGD and tuberculosis during examination due to extended pneumonia. This report is presented because CGD should be considered not only in the presence of skin abscesses and Aspergillus infections, but also in the differential diagnosis for cases with BCG-itis and/or tuberculosis. It should be kept in mind that mycobacterial infections can occur during the course of the disease.

Early Diagnosis and Hematopoietic Stem Cell Transplantation for IL10R Deficiency Leading to Very Early-Onset Inflammatory Bowel Disease Are Essential in Familial Cases.

Alterations of immune homeostasis in the gut may result in development of inflammatory bowel disease. A five-month-old girl was referred for recurrent respiratory and genitourinary tract infections, sepsis in neonatal period, chronic diarrhea, perianal abscess, rectovaginal fistula, and hyperemic skin lesions. She was born to second-degree consanguineous, healthy parents. Her elder siblings were lost at 4 months of age due to sepsis and 1 year of age due to inflammatory bowel disease, respectively. Absolute neutrophil and lymphocyte counts, immunoglobulin levels, and lymphocyte subsets were normal ruling out severe congenital neutropenia and classic severe combined immunodeficiencies. Quantitative determination of oxidative burst was normal, excluding chronic granulomatous disease. Colonoscopy revealed granulation, ulceration, and pseudopolyps, compatible with colitis. Very early-onset colitis and perianal disease leading to fistula formation suggested probability of inherited deficiencies of IL-10 or IL-10 receptor. A mutation at position c.G477A in exon of the IL10RB gene, resulting in a stop codon at position p.W159X, was identified. The patient underwent myeloablative hematopoietic stem cell transplantation from full matched father at 11 months of age. Perianal lesions, chronic diarrhea, and recurrent infections resolved after transplantation. IL-10/IL-10R deficiencies must be considered in patients with early-onset enterocolitis.

The experience of canakinumab in renal amyloidosis secondary to Familial Mediterranean fever.

INTRODUCTION: Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by self-limited recurrent attacks of fever and serositis. Patients may develop renal amyloidosis. Colchicine prevents attacks and renal amyloidosis. Five to 10 % of the patients with FMF are resistant or intolerant to colchicine. CASE DESCRIPTION: Herein, we reported our experience with clinical-laboratory features and treatment responses of a pediatric FMF patient with amyloidosis treated with canakinumab. We observed a significant decrease in proteinuria and increase growth in the patient. DISCUSSION AND EVALUATION: The most serious complication of FMF is the development of AA type amyloidosis which is characterized by proteinuria. Colchicine is the prototype drug that decreases production of amyloidogenic precursor protein. Occasionally, colchicine inadequate patient is observed, as in our case. Canakinumab is a human anti-IL-1ß monoclonal antibody. Previously, canakinumab efficacy were shown in a limited number of studies. CONCLUSIONS: Our data, though limited to only one patient, emphasize that therapeutic intervention with canakinumab seems to be improve kidney function in colchicine-resistant FMF with renal amyloidosis.

Three different classifications, B lymphocyte subpopulations, TNFRSF13B (TACI), TNFRSF13C (BAFF-R), TNFSF13 (APRIL) gene mutations, CTLA-4 and ICOS gene polymorphisms in Turkish patients with common variable immunodeficiency.

B lymphocyte subpopulations, previously defined classification schemes (Freiburg, Paris, EuroClass), TNFRSF13B (TACI), TNFRSF13C (BAFF-R), TNFSF13 (APRIL) gene mutations, CTLA-4 and ICOS gene polymorphisms were analyzed in 25 common variable immunodeficiency (CVID) patients and 25 healthy controls. Patients were also divided into two subgroups due to some disease severity criteria. SG (severe disease group) (n:11) included patients who have splenomegaly and/or granulomatous diseases and/or bronchiectasis and/or lower baseline IgG values (<270 mg/dl). MG (moderate disease group) (n:14) patients diagnosed as having ESID/PAGID criteria but does not fulfill SG inclusion criteria. The onset of infectious symptoms and age at diagnosis were 50.0 ± 45.7 and 78.5 ± 54.5 months, respectively. Parental consanguinity rate was 54.5% in SG and 7.1% in MG. Switched-memory B cells (CD19 + 27 + IgD-IgM-) showed significant decrease in CVID patients and these cells were also significantly lower in SG compared to MG. CVID patients had significantly higher percentages of CD19 + κ + B cells and CD19 + λ + B cells than healthy controls. Freiburg classification: 87.5% of patients (n:21) were in group I and 12.5% were in Group II. Eighteen (75%) CVID patients with a low percentage of CD21(low) B cells were in Group Ib while three patients classified as Group Ia. The significantly lower levels of IgG and IgA in Group Ia is a novel finding. The percentages of patients for Paris Classification groups MB0, MB1, MB2 were 88%, 4% and 8%, respectively. There was a significant increase of splenomegaly, lymphadenopathy and autoimmune cytopenia in Group MB0. EuroClass: 45.8% of patients were smB+ and 54.2% were smB-. Splenomegaly and lymphadenopathy were significantly higher in smB- group. TACI: One patient carried heterozygous C104R mutation which was known as disease causing. APRIL: G67R and N96S SNPs were detected in most of the patients and healthy controls. BAFF-R: P21R/H159Y compound heterozygous mutation (n:1) and P21R heterozygous mutations (n:3) were detected. +49 A > G changes in exon 1 of CTLA-4 gene: GG and AG genotypes increase the risk of CVID development 1.32 and 2.18 fold, respectively. 1564 T > C polymorphisms on 3'UTR region in exon 2 of ICOS gene was not found to be significantly different in CVID patients. CVID classifications were not helpful in determining the genetic etiology of CVID.

X-Linked Lymphoproliferative Syndrome and Common Variable Immunodeficiency May Not Be Differentiated by SH2D1A and XIAP/BIRC4 Genes Sequence Analysis.

The X-linked lymphoproliferative syndrome (XLP) is a rare, inherited immunodeficiency characterized by recurrent episodes of hemophagocytic lymphohistiocytosis, hypogammaglobulinemia, and/or lymphomas. Recently, X-linked inhibitor of apoptosis (XIAP/BIRC4) gene defects, in families with XLP but without SH2D1A gene defects, has been defined. The distinction from primary immunodeficiencies with a defined genetic cause is mandatory. A six-year-old male patient was admitted with the complaints of persistent general lymphadenopathy, for two years had fever, bilateral cervical multiple microlymphadenopathy, hepatic/splenic enlargement with laboratory findings as decreased serum immunoglobulins, negative EBV VCA IgM (viral capsid antigen) and anti-EBV EA (antibody to early D antigen), positive EBV VCA IgG (viral capsid antigen) and EBV EBNA (antibody to nuclear antigen). SH2D1A gene analysis was negative. XIAP/BIRC4 sequencing revealed two novel single nucleotide variants (exon 7, 1978G > A, and 1996T > A) in the 3'UTR of the gene in both patient and mother which were not disease causing. XIAP protein expression was found to be normal. The clinical and laboratory resemblance, no gene mutations, and normal XIAP protein expression led us to think that there may be another responsible gene for XLP. The patient will to be followed up as CVID until he presents new diagnostic signs or until the identification of a new gene.

Study of patients with Hyper-IgM type IV phenotype who recovered spontaneously during late childhood and review of the literature.

UNLABELLED: Hyper-IgM syndromes are characterized by normal or elevated serum IgM levels with the absence or reduced levels of other immunoglobulins. There are some patients with defective class-switch recombination (CSR) who do not have CD40L, CD40, AID, and UNG defects. The aim of this study is to determine the B-cell functions of patients with Hyper-IgM type 4 phenotype. Ten patients (seven males and three females) 84.2 ± 16.5 months of age with initial low serum IgG and IgA and high or normal IgM levels were included. Clinically, 50% had recurrent upper respiratory tract, 10% urinary tract, 10% lower respiratory tract infections, and 30% had mixed type infections. Lymphoid hyperplasia, overt autoimmune manifestations, or malignancy was not noted. Seven of 10 patients were studied twice; at the age of 34.2 ± 13.7 and at 86.6 ± 12.3 months. Absolute lymphocyte counts and lymphocyte subsets were normal in all cases. All of them had normal expression of CD40 on B cells and CD40L on activated T cells for males. At first examination, all patients had normal in vitro sCD40L+rIL-4-induced B cell proliferation response and somatic hypermutation but CSR towards IgE was absent. AID and UNG genes did not show any abnormalities. All showed improvement in both clinical findings and Ig levels during the follow-up period of 55.8 ± 14.8 months. Ages for normalization of IgG and IgA were 68.2 ± 8.7 and 70.2 ± 21.6 months, respectively. During the second evaluation: In vitro sCD40L+rIL-4-induced B-cell proliferation was normal in all cases, whereas CSR was still abnormal in five of eight patients. Two of the patients had an increase in in vitro CSR response but still low IgG2 subclass levels. Three patients with initially absent in vitro CSR response also normalized. CONCLUSION: Clinical manifestations and immunoglobulin levels of the patients with Hyper-IgM type 4 phenotype recovered in late childhood at about 6 years of age. There was a transient CSR defect which was not observed in cases with transient hypogammaglobulinemia of infancy. Detection of a non-AID or non-UNG associated CSR defect in infancy should be confirmed later on since spontaneous recovery may occur.

Consanguinity rate and delay in diagnosis in Turkish patients with combined immunodeficiencies: a single-center study.

Combined immunodeficiency diseases comprise a group of disorders with different molecular basis. Clinical and immunological phenotypes for each group are extremely heterogenous. The frequency of combined immunodeficiencies may vary in different countries. The most frequent forms of combined immunodeficiency show inherited defects in development of T and/or B lymphocytes. These defects are classified according to immunologic phenotype and are categorized into T-B+ or T-B- including forms with or without natural killer lymphocytes. We report here twenty-three patients (female/male: 12/11) with combined immunodeficiency showing different immunological and clinical phenotypes, majority of whom were admitted because of severe upper and lower respiratory tract infections. Mean age of the study group, mean age at onset of the symptoms, and diagnosis were 47.5 ± 42.2, 11.2 ± 17.3, and 19.5 ± 23.8 months, respectively. There was nearly 8 months time delay between beginning of symptoms and diagnosis. Within the combined immunodeficiency phenotypes, T-B-NK+ category was the most frequent phenotype. Consanguinity was positive in 73.9% (n = 17) of patients while it was about 80.0% (n = 8) in deceased ten children. Bone marrow or umblical cord stem cell transplantation was applied to 11 of them. Three patients deceased after transplantation and seven patients deceased without transplantation. Twelve patients are being followed by prophylactic treatment. In conclusion; combined immunodeficiencies are frequent in our country because of high rate of consanguinity. T-B- combined immunodeficiencies are more often observed, and infants presenting severe infections beginning in the first 3 months of life have to be examined for combined immunodeficiencies. Shortening of time delay in diagnosis will increase success of life-saving treatment.

Granulomatous pyoderma preceding chronic recurrent multifocal osteomyelitis triggered by vaccinations in a two-year-old boy: a case report.

INTRODUCTION: Chronic recurrent multifocal osteomyelitis is a rare, systemic, aseptic, inflammatory disorder that involves different sites. Pathogenesis of chronic recurrent multifocal osteomyelitis is currently unknown. CASE PRESENTATION: A two-year-old Caucasian boy, diagnosed with chronic recurrent multifocal osteomyelitis with granulomatous pyoderma following routine vaccinations is presented for the first time in the literature. CONCLUSION: We conclude that antigen exposures might have provoked this inflammatory condition for our case. Skin and/or bone lesions following vaccinations should raise suspicion of an inflammatory response such as chronic recurrent multifocal osteomyelitis only after thorough evaluation for chronic infection, autoimmune, immunodeficiency or vasculitic diseases.