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Severe combined immunodeficiency, SCID, is a pediatric emergency that represents the most critical group of inborn errors of immunity (IEI). Affected infants present with early onset life-threatening infections due to absent or non-functional T cells. Without early diagnosis and curative treatment, most die in early infancy. As most affected infants appear healthy at birth, newborn screening (NBS) is essential to identify and treat patients before the onset of symptoms. Here, we report 47 Brazilian patients investigated between 2009 and 2020 for SCID due to either a positive family history and/or clinical impression and low TRECs. Based on clinical presentation, laboratory finding, and genetic information, 24 patients were diagnosed as typical SCID, 14 as leaky SCID, and 6 as Omenn syndrome; 2 patients had non-SCID IEI, and 1 remained undefined. Disease onset median age was 2 months, but at the time of diagnosis and treatment, median ages were 6.5 and 11.5 months, respectively, revealing considerable delay which affected negatively treatment success. While overall survival was 51.1%, only 66.7% (30/45) lived long enough to undergo hematopoietic stem-cell transplantation, which was successful in 70% of cases. Forty-three of 47 (91.5%) patients underwent genetic testing, with a 65.1% success rate. Even though our patients did not come from the NBS programs, the diagnosis of SCID improved in Brazil during the pilot programs, likely due to improved medical education. However, we estimate that at least 80% of SCID cases are still missed. NBS-SCID started to be universally implemented in the city of São Paulo in May 2021, and it is our hope that other cities will follow, leading to early diagnosis and higher survival of SCID patients in Brazil.

Autoimmune polyendocrine syndrome type 1 (APS1) is characterized by multiorgan autoimmunity. We aim at characterizing a multi-center Brazilian cohort of APS1 patients by clinical evaluation, searching mutation in the AIRE gene, measuring serum autoantibodies, and investigating correlations between findings. We recruited patients based on the clinical criteria and tested them for AIRE mutations, antibodies against interferon type I and interleukins 17A, 17F and 22. We identified 12 unrelated families (13 patients) with typical signs of APS1 in the proband, and the screening of relatives recognized an asymptomatic child. Candidiasis was present in all cases, and 19 other manifestations were observed. All patients carried one of 10 different mutations in AIRE, being 3 new ones, and were positive for anti-interferon type I serum antibody. Anti-interleukin-17A levels inversely correlated with the number of manifestations in each patient. This negative correlation may suggest a protective effect of anti-interleukin-17A with a potential therapeutic application.

The results of hematopoietic stem cell transplant (HSCT) for primary immunodeficiency diseases (PID) have been improving over time. Unfortunately, developing countries do not experience the same results. This first report of Brazilian experience of HSCT for PID describes the development and results in the field. We included data from transplants in 221 patients, performed at 11 centers which participated in the Brazilian collaborative group, from July 1990 to December 2015. The majority of transplants were concentrated in one center (n = 123). The median age at HSCT was 22 months, and the most common diseases were severe combined immunodeficiency (SCID) (n = 67) and Wiskott-Aldrich syndrome (WAS) (n = 67). Only 15 patients received unconditioned transplants. Cumulative incidence of GVHD grades II to IV was 23%, and GVHD grades III to IV was 10%. The 5-year overall survival was 71.6%. WAS patients had better survival compared to other diseases. Most deaths (n = 53) occurred in the first year after transplantation mainly due to infection (55%) and GVHD (13%). Although transplant for PID patients in Brazil has evolved since its beginning, we still face some challenges like delayed diagnosis and referral, severe infections before transplant, a limited number of transplant centers with expertise, and resources for more advanced techniques. Measures like newborn screening for SCID may hasten the diagnosis and ameliorate patients' conditions at the moment of transplant.

Setting As conclusive data on the performance of interferon-gamma release assays (IGRAs) in paediatric TB are lacking, many guidelines do not recommend their use for TB diagnosis in this population in Brazil. Objective To evaluate the performance of an IGRA by investigating its concordance with the tuberculin skin test (TST) and the role of IGRAs in clinical management and treatment outcomes in children with TB. Design A historic cohort study was used to evaluate the performance of T-SPOT®.TB (ELISpot) and other tests, such as the TST, in paediatric patients with or without immunodeficiency who were under investigation for latent tuberculous infection (LTBI) or active tuberculosis (TB). Results Of 86 paediatric patients evaluated, 41 (48%) were immunocompetent and 45 (52%) immunocompromised. All patients underwent T-SPOT.TB, while 63 underwent both ELISpot and TST; test results were concordant in 50 patients (79.4%): 22/31 (71%) in immunocompetent (κ = 0.418, P = 0.02) and 28/32 (87.5%) in immunocompromised patients (κ = 0.526, P = 0.003). TB was diagnosed on the basis of the ELISpot result in 21% (18/86) cases; the contribution of the ELISpot assay was greater in immunocompetent patients than in those who were immunocompromised (13/41, 31.7% vs. 5/45, 11.1%, χ2 P = 0.038). Conclusion ELISpot and TST results were moderately concordant in both groups of patients. ELISpot contribution was higher among immunocompetent patients than among immunocompromised patients.

Background Ataxia-telangiectasia (AT) is a well-known primary immunodeficiency with recurrent sinopulmonary infections and variable abnormalities in both the humoral and cellular immune system. Dysfunctions in immunoglobulin production, reduced number of B cells, and B-cell receptor excision circles copies have been reported. We aimed to understand the immunological mechanisms involving the humoral compartment in AT patients by analysing peripheral blood B cells subsets, B-T lymphocyte cooperation through the expression of CD40 and CD40 ligand (CD40L), and cytokines involved in class-switch recombination production. Methods We compared the proportion of B-cell subsets, the expression of CD40/CD40L, and the plasma levels of IL-6 and IFN-γ of 18 AT patients and 15 healthy age-sex-matched controls using flow cytometry. Results We found that some steps in peripheral B cell development were altered in AT with a pronounced reduction of cell-surface CD40 expression. The proportions of transitional and naive-mature B cells were reduced, whereas CD21-low, natural effector memory, IgM-only memory, and IgG atypical memory B cells were present in a higher proportion. Conclusions These findings revealed a disturbed B-cell homeostasis with unconventional maturation of B lymphocyte memory cells, which can explain the consequent impairment of humoral immunity.

Background This is a prospective study that assessed pneumococcal antibody levels in PID patients under intravenous immunoglobulin (IVIG) treatment using different brands. Methods Twenty-one patients receiving regular IVIG every 28 days were invited to participate: 12 with common variable immunodeficiency, six with X-linked agammaglobulinaemia and three with hyper-IgM syndrome. One blood sample was collected from each patient just prior to IVIG administration at a three-month time interval during one year. A questionnaire was filled in with patient's demographic data and history of infections during the study period. Streptococcus pneumoniae antibodies against six serotypes (1, 5, 6B, 9V, 14 and 19F) were assessed by ELISA both in patients’ serum (trough levels) and in IVIG samples. Results Median total IgG trough serum levels were 7.91 g/L (range, 4.59–12.20). All patients had antibody levels above 0.35 μg/mL to the six serotypes on all four measurements. However, only 28.6% of patients had pneumococcal antibodies for the six analysed serotypes above 1.3 μg/mL on all four evaluations during the one-year period. No correlation was found between IgG trough levels and pneumococcal specific antibodies. Eighteen of the 21 patients (85.7%) had infections at some point during the 12-month follow-up, 62/64 (96.9%) clinically classified in respiratory tract infections, four of which were pneumonia. Conclusions Pneumococcal antibodies are present in a high range of concentrations in sera from PID patients and also in IVIG preparations. Even maintaining a recommended IgG trough level, these patients can be susceptible to these bacteria and that may contribute to recurrent respiratory infections.

diagnosis of primary immunodeficiency diseases (PID) is still a challenge in many countries in Latin America (LA), especially those that face social and economic problems. The creation of a society was fundamental to combine efforts that resulted in an effective educational program, establishment of a registry and a network to improve diagnosis. Areas covered: The focus of this article is to portray the scenario of PID in LA covering different aspects from different countries. For this, a questionnaire was sent to countries that participate in the Latin American Society for Immunodeficiencies (LASID) registry, with questions related to PID challenges in LA. We realized that today the greatest challenge is the availability of laboratory tests to investigate newly described PIDs. Expert commentary: Despite being faced with many difficulties, the Latin America Society for Immunodeficiencies is supporting clinical immunologists throughout the continent, which has resulted in a greater awareness of these diseases and an increase in the number of diagnosis.

X-linked agammaglobulinemia (XLA) has been associated with a broad range of infections, but enteroviral disease represents one of the most damaging infections. The risk of enteroviral infection in XLA is lower now than in the setting of intramuscular immunoglobulin or in patients without immunoglobulin replacement, but the rate of infection has not declined significantly in the era of intravenous immunoglobulin replacement. Enteroviruses can cause inflammation of nearly every organ, but in XLA, infections often manifest as dermatomyositis or chronic meningoencephalitis. Difficulty and delay in recognizing symptoms and lack of specific therapy contribute to the poor outcomes. Furthermore, cerebrospinal fluid detection of enteroviruses is not very sensitive. Reluctance to perform brain biopsies can lead to significant delays. The other feature compromising outcomes is the lack of specific therapy. High-dose peripheral and intraventricular immunoglobulin have been used, but failure is still common. New antienteroviral drugs are in development and show promise for immunodeficient patients with life-threatening infections with enterovirus.

Severe combined immunodeficiency (SCID) represents the most lethal form of primary immunodeficiency, with mortality rates of greater than 90% within the first year of life without treatment. Hematopoietic stem cell transplantation and gene therapy are the only curative treatments available, and the best-known prognostic factors for success are age at diagnosis, age at hematopoietic stem cell transplantation, and the comorbidities that develop in between. There are no evidence-based guidelines for standardized clinical care for patients with SCID during the time between diagnosis and definitive treatment, and we aim to generate a consensus management strategy on the supportive care of patients with SCID. First, we gathered available information about SCID diagnostic and therapeutic guidelines, then we developed a document including diagnostic and therapeutic interventions, and finally we submitted the interventions for expert consensus through a modified Delphi technique. Interventions are grouped in 10 topic domains, including 123 "agreed" and 38 "nonagreed" statements. This document intends to standardize supportive clinical care of patients with SCID from diagnosis to definitive treatment, reduce disease burden, and ultimately improve prognosis, particularly in countries where newborn screening for SCID is not universally available and delayed diagnosis is the rule. Our work intends to provide a tool not only for immunologists but also for primary care physicians and other specialists involved in the care of patients with SCID.

Introduction and objectives Vitamin D plays a role in the immune system, however studies regarding this are scarce. This study aimed to evaluate the nutritional status of vitamin D in patients with Common Variable Immunodeficiency (CVID) or Ataxia–Telangiectasia (A–T) and to relate it to body composition, inflammatory and bone metabolism markers. Patients and methods This is a cross-sectional and controlled study involving 24 patients of both sexes (59.3% male), aged 8–56 years, with CVID (n = 15) or A–T (n = 9). The following variables were evaluated: body mass index (BMI), 25-hydroxyvitamin D (25 (OH) D), hepatic profile, parathormone, calcium, phosphorus, alkaline phosphatase, interleukin 6 and high-sensitivity C-reactive protein. Results The median age was 26.0 years. A deficiency of 25 (OH) D was found in four A–T patients (44%) and two CVID patients (13%). Nine patients with CVI (60%) and six with A–T (66.7%) were overweight and underweight, respectively. There was a negative correlation between vitamin D and fat mass in the CVID group, and vitamin D and BMI in the A–T group. Vitamin D was negatively associated with the percentage of total fat among the patients (β – 0.842, 95% CI: −1.5–0.17, p = 0.015), R2 = 0.21, after adjusting for sex and age. Conclusion Vitamin D deficiency occurred in a quarter of the patients although there was no difference between the patient and the control group; without association with bone and inflammation biomarkers. The percentage of fat and BMI were negatively associated with the concentrations of 25 (OH) D.

The use of HLA-identical hematopoietic stem cell transplantation (HSCT) demonstrates overall survival rates greater than 75% for T-B-NK+ severe combined immunodeficiency secondary to pathogenic mutation of recombinase activating genes 1 and 2 (RAG1/2). Limited data exist regarding the use of HSCT in patients with hypomorphic RAG variants marked by greater preservation of RAG activity and associated phenotypes such as granulomatous disease in combination with autoimmunity. We describe a 17-year-old with combined immunodeficiency and immune dysregulation characterized by granulomatous lung disease and autoimmunity secondary to compound heterozygous RAG mutations. A myeloablative reduced toxicity HSCT was completed using an unrelated bone marrow donor. With the increasing cases of immune dysregulation being discovered with hypomorphic RAG variants, the use of HSCT may advance to the forefront of treatment. This case serves to discuss indications of HSCT, approaches to preparative therapy, and the potential complications in this growing cohort of patients with immune dysregulation and RAG deficiency.

Diagnosis of primary immunodeficiency diseases (PID), based on laboratory tests and assessment of T lymphocyte function, is crucial in patients who present with lymphopenia. We evaluated T lymphocyte function in healthy children and adults and in patients and with PID using flow cytometry. Whole blood cultures were stimulated with phytohemagglutinin, purified protein derivate (PPD) and candidin, followed by detection of intracellular interferon-gamma (IFN - gamma) and CD25 membrane expression on CD3+ T cells by flow cytometry. Flow cytometry results were compared with 3H-thymidine (3HTdR) lymproliferation after in vitro cell stimulation and with delayed type hypersensitivity reaction (DTH). Patients with PID had lower intracellular IFN - gamma production than healthy children and healthy adults after PHA stimulation for 18 h ( p = 0.024 and p p = 0.048 and p p p = 0.029). The DTH for PPD was not different between PID and healthy children ( p = 0.281). Intracellular IFN-gamma after PHA stimulation for 18 h and CD25 membrane expression after candidin stimulation for 72 h on CD3+ T cells were most reliable parameters that could discriminate PID patients from healthy children. Our results confirm the high variability in functional cell assays and reinforce the idea that age differences must be taken into consideration during assay evaluation.

The International Collaboration in Asthma, Allergy and Immunology initiated an international coalition among the American Academy of Allergy, Asthma & Immunology; the European Academy of Allergy and Clinical Immunology; the World Allergy Organization; and the American College of Allergy, Asthma & Immunology on common variable immunodeficiency. An author group was formed and then divided into individual committees. Within the committee, teams of authors were subgrouped to generate content for specific sections of the document. Content was derived from literature searches, relevant published guidelines, and clinical experience. After a draft of the document was assembled, it was collectively reviewed and revised by the authors. Where evidence was lacking or conflicting, the information presented represents the consensus expert opinion of the group. The full document was then independently reviewed by 5 international experts in the field, none of whom was among the authors of the original. The comments of these reviewers were incorporated before submission for publication.

Poliovirus has been nearly eliminated as part of a world-wide effort to immunize and contain circulating wild-type polio. Nevertheless, poliovirus has been detected in water supplies and represents a threat to patients with humoral immunodeficiencies where infection can be fatal. To define the risk, we analyzed antibodies to poliovirus 1, 2, and 3 in serum samples collected over a year from patients with primary immunodeficiency diseases (PID) on regular intravenous immunoglobulin (IVIG) replacement. Twenty-one patients on regular IVIG replacement therapy were evaluated: Twelve patients with common variable immune deficiency (CVID), six with X-linked agammaglobulinemia (XLA), and three with hyper IgM syndrome (HIGM). Over 1 year, four blood samples were collected from each of these patients immediately before immunoglobulin infusion. One sample of IVIG administered to each patient in the month before blood collection was also evaluated. Poliovirus antibodies were quantified by seroneutralization assay. All IVIG samples had detectable antibodies to the three poliovirus serotypes. Despite that, only 52.4, 61.9, and 19.0% of patients showed protective antibody titers for poliovirus 1, 2, and 3, respectively. Only two patients (9.5%) had protective antibodies for the three poliovirus serotypes on all samples. Most patients were therefore susceptible to all three poliovirus serotypes. This study demonstrates the need for ongoing vigilance regarding exposure of patients with PID to poliovirus in the community.

(59.4%), granulomata (49.3%), skin infections (42%), chronic diarrhea (41.9%), otitis (29%), sepsis (23.2%), abscesses (21.7%), recurrent urinary tract infection (20.3%), and osteomyelitis (15.9%). Adverse reactions to bacillus Calmette-Gu� (BCG) vaccination were identified in 30% of the studied Latin American CGD cases. The genetic diagnoses of the 71 patients revealed 53 patients from 47 families with heterogeneous mutations in the CYBB gene (five novel mutations:p.W361G,p.C282X,p.W483R,p.R226X,andp.Q93X),16 patientswith the commondeletionc.75_76 del.GTinexon2 ofNCF1 gene, and two patients with mutations in the CYBA gene. Conclusion. The majority of Latin American CGD patients carry a hemizygous mutation in the CYBB gene. They also presented a wide range of clinical manifestations most frequently bacterial and fungal infections of the respiratory tract, skin, and lymph nodes. Thirty percent of the Latin American CGD patients presented adverse reactions to BCG, indicating that this vaccine should be avoided in these patients. # 2015 Wiley Periodicals, Inc.

Some of the recognized actions of vitamin D include immunological effects such as keeping tolerance and to promote protective immunity. These functions are related to the blocking of B cell differentiation and immunoglobulin secretion as well as decreased production of inflammatory cytokines. The aim of this study was to describe the frequency of vitamin D deficiency in patients with primary immunodeficiencies. We studied 31 patients: 14 with Ataxia-telangiectasia (11 male, mean age 13.1±4.9 years) and 17 with Common variable immunodeficiency (8 males, mean age 28.5±11.3 years). Classification of nutritional status and percentage of fat mass were evaluated. 25-hydroxyvitamin D was analyzed by high performance liquid chromatography and deficiency was Short Communication Paulino et al.; BJMMR, 7(12): 1035-1038, 2015; Article no.BJMMR.2015.419 1036 considered when 25-hydroxyvitamin D< 20 ng/mL. Malnutrition was the most common nutritional disorder: 7/14 (50%) and 4/17 (23.5%) in Ataxia-telangiectasia and Common variable immunodeficiency groups, respectively. We found a high percentage of 25-hydroxyvitamin D deficiency in the Ataxia-telangiectasia group 6/14 (42.8%) and Common variable immunodeficiency group 3/17 (17.6%). There was no association between vitamin D deficiency and high-sensitivity C-reactive protein, lymphocyte count (CD3, CD4 and CD8) and body fat percentage. Considering the frequency of autoimmune diseases and infections in patients with primary immunodeficiencies, strict monitoring of the vitamin levels are recommended with the aim to reduce morbidity.

Background and Aims: Evaluate the nutritional status, plasma concentration of vitamin E and markers of cardiovascular risk in ataxia telangiectasia (AT) patients. Methods: Cross-sectional study with 13 patients with AT and 22 healthy controls, evaluating the following factors: nutritional status, food intake, lipid profile, plasma concentration of vitamin E, malondialdehyde and high sensitivity C-reactive protein, linking them with atherosclerosis risk in AT patients. Results: Average age was 14.6 in the AT group, 30.8% were malnourished and 23.1% had stunting. A greater impairment of lean body mass was found in these patients. Concentrations of triglycerides (TG), total cholesterol (CT), LDL-c, non-HDL cholesterol (NHDL-c) were significantly higher in patients and HDL-c, lower. Vitamin E/total lipids and vitamin E/TG ratios were lower in the AT group, and significant inverse correlation between these ratios and NHDL-c, CT/HDL-c, and LDL-c/HDL-c, log TG/HDL-c was observed in the AT group. Alanine aminotransferase correlated directly and significantly with NHDL-c, CT/HDL-c and LDL-c/HDL-c, in patients. Conclusion: The alterations of lipid metabolism biomarkers suggestive of atherosclerotic risk of male AT patients coupled with lower vitamin E/total lipids ratio and low lean body mass may complicate the clinical course of the disease and emphasizes the importance of multidisciplinary care, routine monitoring of cardiovascular biomarkers and appropriate nutritional guidance.

We report on a patient conceived via in vitro fertilization (IVF) with a 22q11.2 deletion due to an unusual unbalanced translocation involving chromosomes 6 and 22 in a karyotype with 45 chromosomes. Cytogenomic studies showed that the patient has a 3.3-Mb deletion of chromosome 22q and a 0.4-Mb deletion of chromosome 6p, which resulted in haploinsufficiency of the genes responsible for the 22q11.2 deletion syndrome and also of the IRF4 gene, a member of the interferon regulatory factor family of transcription factors, which is expressed in the immune system cells. The rearrangement could be due to the manipulation of the embryo or as a sporadic event unrelated to IVF. Translocation involving chromosome 22 in a karyotype with 45 chromosomes is a rare event, with no previous reports involving chromosomes 6p and 22q.

Summary Objective: To evaluate the carotid intima-media complex (CIMC) thickness and lipid metabolism biomarkers associated with cardiovascular risk (CR) in parents of patients with ataxia-telangiectasia and verify an association with gender. Method: A cross-sectional and controlled study with 29 ATM heterozygotes and 14 healthy controls. Biochemical tests and CIMC thickness measurement were performed. Results: The mean CIMC measurement in heterozygous ATM was 0.72 ± 0.1 mm (minimum: 0.5 mm and maximum: 1.0 mm). Noticed high percentage of amounts above 75 percentile compared to the population referential (16 [76.2%]), without any significant statistical differences between the female and the male gender (11/15 [73.3%] vs. 5/6 [83.3%]; p=0.550). The comparison between heterozygous and controls, stratified by gender, showed that in heterozygous ATMs, women had higher concentrations of HDL-c compared to men, as well as higher values of hs-CRP in relation to the control women. In heterozygous ATMs, stratified by gender, the correlation between HDL-c and hs-CRP was inversely proportional and stronger among women, with a tendency to statistical significance. Conclusion: Heterozygous ATMs did not differ from controls in relation to the biomarkers studied related to CR. However, most of them presented increased CIMC, independent predictor of death, risk for myocardial infarction and stroke, compared to the referential for the same age group. This finding suggests CR in the heterozygous ATM and shows to the need to monitor CIMC thickness and nutritional orientations. Resumo Objetivo: Avaliar a espessura do complexo médio-intimal da carótida (CMIC) e os biomarcadores do metabolismo lipídico associados ao risco cardiovascular (RC) em pais de pacientes com ataxia-telangiectasia (AT) e verificar associação com gênero. Método: Estudo transversal prospectivo e controlado com 29 ATM heterozigotos e 14 controles saudáveis. Foram realizados exames bioquímicos e a espessura do CMIC por ultrassonografia. Resultados: A média da medida do CMIC nos ATM heterozigotos foi de 0,72± 0,1 mm (mínimo: 0,5 mm e máximo: 1,0 mm). Observou-se elevado percentual de valores acima do percentil 75 em relação ao referencial populacional (16 [76,2%]), sem diferença estatisticamente significante entre o gênero feminino e o masculino (11/15 [73,3%] vs. 5/6 [83,3%]; p=0.550). A comparação entre os ATM heterozigotos e os controles, estratificados por gênero, mostrou que, nos ATM heterozigotos, as mulheres tinham maiores concentrações de HDL-c em comparação aos homens, e valores mais elevados de PCR-us em relação às mulheres controle. Nos ATM heterozigotos, estratificando segundo gênero, a correlação entre HDL-c e PCR-us foi inversamente proporcional e mais forte entre as mulheres, com tendência à significância estatística. Conclusão: Os ATM heterozigotos não diferiram dos controles em relação aos biomarcadores estudados relacionados ao RC. Entretanto, a maioria deles apresentou aumento na espessura do CMIC, preditor independente de morte, risco para infarto do miocárdio e AVC, quando comparado ao referencial para a mesma faixa etária. Esse achado sugere RC nos ATM heterozigotos e aponta para a necessidade de monitoramento da espessura do CMIC e de orientações nutricionais.

This study investigated phenotypic and functional characteristics of lymphocytes in children with common variable immunodeficiency (CVID) and unclassified hypogammaglobulinemia (UH), as well as B-cell subsets in non-consanguineous parents. Blood samples of 30 children, CVID (n = 9), UH (n = 9), healthy donors HD (n = 12), and 19 adults (parents and controls) were labeled by a combination of surface markers to identify CD4, CD8 T-cell and B-cell subpopulations. T-cell cytokine production in children was analyzed in vitro after stimulation with phytohemagglutinin (PHA) and tetanus toxoid. We observed low percentages of switched memory B cells in children with CVID, increase in total CD4+ T-cell counts, and high percentages of transitional B cells only in UH group. Analysis of T-cell immunity showed that CVID children had decreased percentages of CD8+ IFN-γ-producing cells after stimulation with PHA and tetanus toxoid. Parent of children with CVID had low percentages of naive B cell and increased percentages of memory B cells in comparison with controls. These results suggest that (i) early combined immune defect in children with CVID and (ii) a possible familial B-cell disturbance in pediatric CVID.

International audience; X-linked recessive ectodermal dysplasia with immunodeficiency is a rare primary immunodeficiency caused by hypomorphic mutations of the gene encoding the nuclear factor κB essential modulator (NEMO) protein. This condition displays enormous allelic, immunological, and clinical heterogeneity, and therapeutic decisions are difficult because NEMO operates in both hematopoietic and nonhematopoietic cells. Hematopoietic stem cell transplantation (HSCT) is potentially life-saving, but the small number of case reports available suggests it has been reserved for only the most severe cases. Here, we report the health status before HSCT, transplantation outcome, and clinical follow-up for a series of 29 patients from unrelated kindreds from 11 countries. Between them, these patients carry 23 different hypomorphic mutations. HSCT was performed from HLA-identical related donors (n = 7), HLA-matched unrelated donors (n = 12), HLA-mismatched unrelated donors (n = 8), and HLA-haploidentical related donors (n = 2). Engraftment was documented in 24 patients, and graft-versus-host disease in 13 patients. Up to 7 patients died 0.2 to 12 months after HSCT. The global survival rate after HSCT among NEMO-deficient children was 74% at a median follow-up after HSCT of 57 months (range, 4-108 months). Preexisting mycobacterial infection and colitis were associated with poor HSCT outcome. The underlying mutation does not appear to have any influence, as patients with the same mutation had different outcomes. Transplantation did not appear to cure colitis, possibly as a result of cell-intrinsic disorders of the epithelial barrier. Overall, HSCT can cure most clinical features of patients with a variety of mutations.

Antibodies are an essential component of the adaptative immune response and hold long-term memory of the immunological experiences throughout life. Antibody defects represent approximately half of the well-known primary immunodeficiencies requiring immunoglobulin replacement therapy. In this article, the authors review the current indications and therapeutic protocols in the Latin American environment. Immunoglobulin replacement therapy has been a safe procedure that induces dramatic positive changes in the clinical outcome of patients who carry antibody defects. COL0012426

Background Patients with X-linked hyper-IgM syndrome caused by CD40 ligand (CD40L) deficiency often present with episodic, cyclic, or chronic neutropenia, suggesting abnormal neutrophil development in the absence of CD40L-CD40 interaction. However, even when not neutropenic and despite immunoglobulin replacement therapy, CD40L-deficient patients are susceptible to life-threatening infections caused by opportunistic pathogens, suggesting impaired phagocyte function and the need for novel therapeutic approaches. Objectives We sought to analyze whether peripheral neutrophils from CD40L-deficient patients display functional defects and to explore the in vitro effects of recombinant human IFN-γ (rhIFN-γ) on neutrophil function. Methods We investigated the microbicidal activity, respiratory burst, and transcriptome profile of neutrophils from CD40L-deficient patients. In addition, we evaluated whether the lack of CD40L in mice also affects neutrophil function. Results Neutrophils from CD40L-deficient patients exhibited defective respiratory burst and microbicidal activity, which were improved in vitro by rhIFN-γ but not soluble CD40L. Moreover, neutrophils from patients showed reduced CD16 protein expression and a dysregulated transcriptome suggestive of impaired differentiation. Similar to CD40L-deficient patients, CD40L knockout mice were found to have impaired neutrophil responses. In parallel, we demonstrated that soluble CD40L induces the promyelocytic cell line HL-60 to proliferate and mature by regulating the expression of genes of the same Gene Ontology categories (eg, cell differentiation) when compared with those dysregulated in peripheral blood neutrophils from CD40L-deficient patients. Conclusion Our data suggest a nonredundant role of CD40L-CD40 interaction in neutrophil development and function that could be improved in vitro by rhIFN-γ, indicating a potential novel therapeutic application for this cytokine.

Summary. Background: Ataxia telangiectasia (AT) is a genetic syndrome caused by a mutation of chromosome 11. The clinical features are cerebellar ataxia, telangiectasia, and progressive loss of muscular coordination, including an inefficient cough secondary to progression of neurological disease. Objective: To evaluate the effects of inspiratory muscle training (IMT) on ventilation, lung volume, dyspnoea, respiratory muscle strength, and quality of life in patients with AT. Methods: A longitudinal study was conducted with 11 AT patients and nine healthy volunteers. Ventilometry, subjective sensation of dyspnoea, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and quality of life were assessed before and after a 24-week IMT program. The IMT load used was set at 60% of the MIP, and the training was performed for 20 min daily. Results: Patientswith AT had lower height and weight and also had lower respiratory muscle strength and lung volume compared with healthy volunteers. Furthermore, patients with AT showed a significant improvement when pre- and post-IMTwere comparedfor ventilatory pattern: Vt (476.5 � 135 ml vs. 583.3 � 66 ml, P ¼ 0.015) and f (23.3 � 6 rpm vs. 20.4 � 4r pm, P ¼ 0.018), and VC (1,664 � 463 ml/kg vs. 2,145 � 750 ml/kg, P ¼ 0.002). IMT also significantly improved the sensation of dyspnoea (median 0.5; minimum 0; maximum 1.0; P ¼ 0.022) and respiratory muscle strength: MIP (� 22.2 � 2 cmH2 Ov s.� 38 � 9 cmH2O, P < 0.001) and MEP (29 � 7 cmH2 Ov s. 40� 8 cmH2O, P ¼ 0.001). The health and vitality domains of the SF-36 also showed significant improvement (P ¼ 0.009 and P ¼ 0.014, respectively) post-IMT. Conclusion: IMT was effective in improving ventilatory pattern, lung volume, respiratory muscle strength, and the health and vitality domains for quality of life in patients with AT. IMT may be an effective adjunct therapy to drug treatment for patients with AT.

The subspecialty of pediatric allergy and immunology in Brazil is in its early years and progressing steadily. This review highlights the research developed in the past years aiming to show the characteristics of allergic and immunologic diseases in this vast country. Epidemiologic studies demonstrated the high prevalence of asthma in infants, children, and adolescents. Mortality rates and average annual variation of asthma hospitalization have reduced in all pediatric age groups. Indoor aeroallergen exposure is excessively high and contributes to the high rates of allergy sensitization. Prevalence of food allergy has increased to epidemic levels. Foods (35%), insect stings (30%), and drugs (23%) are the main etiological agents of anaphylaxis in children and adolescents. Molecular diagnosis of primary immunodeficiencies (PID) showed a high incidence of fungal infections including paracoccidioidomycosis in X-linked hyper-IgM syndrome, and the occurrence of BCG adverse reactions or other mycobacterial infections in patients with chronic granulomatous disease. Education in pediatric allergy and immunology is deficient for medical students, but residency programs are effective in training internists and pediatricians for the practice of allergy. The field of PID requires further training. Last, this review is a tribute to Prof. Dr. Charles Naspitz, one of the pioneers of our specialty in Brazil.

Implementing precise techniques in routine diagnosis of chronic granulomatous disease (CGD), which expedite the screening of molecular defects, may be critical for a quick assumption of patient prognosis. This study compared the efficacy of single-strand conformation polymorphism analysis (SSCP) and high-performance liquid chromatography under partially denaturing conditions (dHPLC) for screening mutations in CGD patients. We selected 10 male CGD patients with a clinical history of severe recurrent infections and abnormal respiratory burst function. gDNA, mRNA and cDNA samples were prepared by standard methods. CYBB exons were amplified by PCR and screened by SSCP or dHPLC. Abnormal DNA fragments were sequenced to reveal the nature of the mutations. The SSCP and dHPLC methods showed DNA abnormalities, respectively, in 55% and 100% of the cases. Sequencing of the abnormal DNA samples confirmed mutations in all cases. Four novel mutations in CYBB were identified which were picked up only by the dHPLC screening (c.904 insC, c.141+5 g>t, c.553 T>C, and c.665 A>T). This work highlights the relevance of dHPLC, a sensitive, fast, reliable and cost-effective method for screening mutations in CGD, which in combination with functional assays assessing the phagocyte respiratory burst will contribute to expedite the definitive diagnosis of X-linked CGD, direct treatment, genetic counselling and to have a clear assumption of the prognosis. This strategy is especially suitable for developing countries.

In today's global economy and affordable vacation travel, it is increasingly important that visitors to another country and their physician be familiar with emerging infections, infections unique to a specific geographic region, and risks related to the process of travel. This is never more important than for patients with primary immunodeficiency disorders (PIDD). A recent review addressing common causes of fever in travelers provides important information for the general population Thwaites and Day (N Engl J Med 376:548-560, 2017). This review covers critical infectious and management concerns specifically related to travel for patients with PIDD. This review will discuss the context of the changing landscape of infections, highlight specific infections of concern, and profile distinct infection phenotypes in patients who are immune compromised. The organization of this review will address the environment driving emerging infections and several concerns unique to patients with PIDD. The first section addresses general considerations, the second section profiles specific infections organized according to mechanism of transmission, and the third section focuses on unique phenotypes and unique susceptibilities in patients with PIDDs. This review does not address most parasitic diseases. Reference tables provide easily accessible information on a broader range of infections than is described in the text.

CD40 ligand (CD40L) deficiency or X-linked hyper-IgM syndrome (X-HIGM) is a well-described primary immunodeficiency in which Pneumocystis jiroveci pneumonia is a common clinical feature. We have identified an unusual high incidence of fungal infections and other not yet described infections in a cohort of 11 X-HIGM patients from nine unrelated Brazilian families. Among these, we describe the first case of paracoccidioidomycosis (PCM) in X-HIGM. The molecular genetic analysis of CD40L was performed by gene sequencing and evaluation of CD40L protein expression. Nine of these 11 patients (82%) had fungal infections. These included fungal species common to CD40L deficiency (P. jiroveci and Candida albicans) as well as Paracoccidioides brasiliensis. One patient presented with PCM at age 11 years and is now doing well at 18 years of age. Additionally, one patient presented with a simultaneous infection with Klebsiella and Acinetobacter, and one with condyloma caused by human papilloma virus. Molecular analysis revealed four previously described CD40L mutations, two novel missense mutations (c.433 T G and c.476 G C) resulting in the absence of CD40L protein expression by activated CD4(+) cells and one novel insertion (c.484_485insAA) within the TNFH domain leading to a frame shift and premature stop codon. These observations demonstrated that the susceptibility to fungal infections in X-HIGM extends beyond those typically associated with X-HIGM (P. jiroveci and C. albicans) and that these patients need to be monitored for those pathogens.

Objective The aim of this study was to evaluate pulmonary complications in patients with primary antibody deficiency (X-linked agammaglobulinaemia [XLA] and common variable immunodeficiency [CVID]). Methods Thirty patients over six years of age regularly followed in a reference out-patient clinic on primary immunodeficiency were studied. All of them have been treated with intravenous immunoglobulin (IVIG) replacement therapy. Pulmonary complications were evaluated analysing clinical data (medical records review), lung function test (spirometry) and pulmonary imaging (chest computed tomography [CCT]). Results Patients with normal CCT (N=14) and those with abnormal CCT (N=16) have shown no differences regarding the age at onset of symptoms, age of diagnosis, and duration of IVIG treatment. The mean number of pneumonia episodes before IVIG replacement was significantly higher among patients with abnormal CCT (4 vs 7 episodes, p=0.008). CCT abnormalities observed in 16 patients were: bronchiectasis (12/16); peribronchial thickening (3/16); air trapping (5/16); lung volume reduction (4/16); atelectasis (2/16), follicular bronchiolitis and ground-glass abnormality (2/16) and parenchyma nodule (1/16). Lung function tests showed ventilatory disturbance in 18/30: obstructive pattern in 38.8%, restrictive pattern in 44.4%, and mix pattern in 16.7%. There were no significant differences in lung function between those with and without CCT abnormalities. Negative significant correlations were observed between lung function and number of episodes of pneumonia. Chronic persistent cough was associated with a reduction in lung function. Conclusions Pulmonary complications are not rare in patients with antibody deficiencies and they must be monitored.

Early diagnosis and appropriate therapy are essential for the best prognosis and quality of life in patients with primary immunodeficiency diseases (PIDDs). Experts from several Latin American countries have been meeting on a regular basis as part of an ongoing effort to improve the diagnosis and treatment of PIDD in this region. Three programmes are in development that will expand education and training and improve access to testing facilities throughout Latin America. These programmes are: an educational outreach programme (The L-Project); an immunology fellowship programme; and the establishment of a laboratory network to expand access to testing facilities. This report provides the status of these programmes based on the most recent discussions and describes the next steps toward full implementation of these programmes.

We studied the levels of immunoglobulins in colostrum, milk and sera from two common variable immunodeficiency (CVID) mothers (M1 and M2), and in sera from their newborn infants. During pregnancy they continued intravenous immunoglobulin therapy (IVIG). Antibody levels from maternal and cord blood collected at delivery and colostrum and milk, collected on the 3rd and 7th post-partum days, respectively, were analyzed. Although cord/maternal blood ratios of total immunoglobulins and subclasses, as well as specific antibodies differed between M1 and M2, both showed good placental transfer of anti-protein and anti-polysaccharide antibodies, despite lower cord/maternal blood ratios in M2. Anti-Streptococcus pneumoniae antibody avidity indexes were similar between paired maternal and cord serum. Both mothers' colostrum and milk samples showed only traces of IgA, and IgM and IgG levels in colostrum were within normal range in M1, whereas M2 presented elevated IgG and low IgM levels, when compared with healthy mothers. The study of colostrum and milk activity showed that they strongly inhibited enteropathogenic Escherichia coli adhesion in vitro. CVID patients must be informed about the relevance of regular IVIG administration during pregnancy, not only for their own health but also for their immune immature offspring. Breast-feeding should be encouraged as colostra from these CVID patients strongly inhibited E. coli adhesion to human epithelial cells thus providing immunological protection plus nutritional and psychological benefits for the infant.

Universidade Federal de Sao Paulo, Dept Pediat, Div Allergy Clin Immunol & Rheumatol, Sao Paulo, Brazil

This study evaluated the vaccination response to Haemophilus influenzae type b (Hib) in malnourished pregnant women (MN), cord blood (CB) and in infants at two and six months of age for comparison with a control group (C). Twenty-eight malnourished pregnant women and 29 pregnant controls were immunized with conjugated Act-HIB(R) in the third trimester of pregnancy. Blood samples were collected from all before the immunization, during labor (post immunization), and from CB. All infants were immunized with Hib vaccine according to normal vaccine schedule and sera were collected at two and six months of age. Antibody levels to polyribosylribitol phosphate (PRP) were similar for both groups. Preimmunization: MN 1.94 microg/mL, C 1.68 microg/mL; post-vaccination: MN 18.53 microg/mL and C 17.55 microg/mL; in CB from MN 14.46 microg/mL and from C 17.04 microg/mL. Infants from MN and C mothers presented respectively at two months: 5.18 microg/mL and 8.60 microg/mL and at six months: MN 3.42 microg/mL and C 2.18 microg/mL. Antibody levels were similar in both groups studied (p = 0.485), however the vertical transmission rate was 14% lower in the MN pregnant group. Levels of antibodies > 0.15 microg/mL were found in all newborns from the MN pregnant group. Pregnant MN presented an immunological response to Hib vaccine similar to group C, however, vertical transmission rate of antibodies to PRP in the MN pregnant group was 14% lower than that in C, suggesting a less efficient passage of antibodies within this group.

Purpose Health-related quality of life (HRQOL) has not been examined in patients with predominant antibody deficiency both pre- and post-immunoglobulin G (IgG) treatment initiation. HRQOL and health resource utilization (HRU) were assessed in newly diagnosed patients with primary immunodeficiency disease (PIDD) pre- and 12 months post-IgG treatment initiation. Methods Adults (age ≥18 years) completed the 36-item Short Form Health Survey, version 2; pediatric patients (PP)/caregivers completed the Pediatric Quality of Life Inventory (PedsQL). Scores were compared with normative data from the US general population (GP) and patients with other chronic conditions (OCC). Results Seventeen adult patients (APs), 8 PPs, and 8 caregivers completed baseline assessments. APs had significantly lower baseline mean physical component summary scores versus GP (37.4 vs 50.5, p

Introduction: Common variable immunodeficiency and X-linked agammaglobulinaemia are primary immunodeficiencies classified as antibody deficiencies, and they both result in hypogammaglobulinaemia. Objective: Evaluate the lipid profile and other cardiovascular risk biomarkers in CVID and XLA patients. Methods: In total, 24 patients and 12 healthy controls matched by age and gender were included in the study. We evaluated anthropometric measurements, and seric total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), triglycerides (TG), apo A-I, small dense LDL (sdLDL), C-reactive protein (CRP), and tumour necrosis factor alpha (TNF-alpha), myeloperoxidase (MPO), cholesteryl ester transfer protein (CETP), and lecithin cholesterol acyltransferase (LCAT) were assessed. Results: CRP (p = 0.008) and TNF-alpha (p < 0.001) concentrations were significantly higher, whereas HDL-c (p = 0.025) and apo A-I (p = 0.013) levels were significantly lower in patients than in the controls. In the patient group, a negative and significant correlation was observed between HDL-c and TNF-alpha (r = -0.406; p = 0.049) and between HDL-c and TG (r = -0.641; p = 0.001). Conclusion: Common variable immunodeficiency and X-linked agammaglobulinaemia patients presented themselves with increased inflammatory markers associated with a decreased HDL-c and apo A-I levels, which can predispose to a high cardiovascular risk.

Neonates born to renal transplanted women are exposed in utero to immunosuppressors and to antenatal conditions that may predispose the neonate to a high risk of prematurity and intrauterine growth retardation. These factors might interfere with the transfer of maternal IgG immunity. Total IgG levels and specific antibodies to measles, varicella, tetanus, Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae (serotypes 4,6B,9V,14,18C,19F and 23F) were evaluated on maternal and cord blood samples of 23 sets of renal transplanted women and their newborns and 32 sets of healthy women-newborns at term. Total IgG levels were measured by nephelometry and specific antibodies, by ELISA. Renal transplanted mothers had lower median tetanus antibodies (0.67 IU/mL) than controls (1.53 IU/mL; p = 0.017). Neonates from renal transplanted mothers had lower median tetanus antibodies (0.95 IU/mL) than controls (1.97 IU/mL, p = 0.008). Antibodies to measles, varicella, Hib and the 7 serotypes of S. pneumoniae were similar between groups. Maternal antibodies were associated with an increase in neonatal antibodies for all antigens; gestational age was associated with an increase in Hib neonatal antibodies. Preeclampsia was associated with a decrease in neonatal total IgG and serotype 4 S. pneumoniae antibodies; chronic hypertension was associated with a decrease in neonatal serotype 6B S. pneumoniae antibodies. As neonates from transplanted women may be born with lower tetanus antibodies than controls, efforts should be made to keep maternal vaccines up-to-date. Clinical antenatal care with control of preeclampsia, chronic hypertension and prevention of premature delivery might also contribute to neonatal antibody levels to specific antigens at birth.

This is the second report on the continuing efforts of LAGID to increase the recognition and registration of patients with primary immunodeficiency diseases in 12 Latin American countries: Argentina, Brazil, Chile, Colombia, Costa Rica, Honduras, Mexico, Panama, Paraguay, Peru, Uruguay, and Venezuela. This report reveals that from a total of 3321 patients registered, the most common form of primary immunodeficiency disease was predominantly antibody deficiency (53.2%) with IgA deficiency reported as the most frequent phenotype. This category was followed by 22.6% other well-defined ID syndromes, 9.5% combined T- and B-cell inmunodeficiency, 8.6% phagocytic disorders, 3.3% diseases of immune dysregulation, and 2.8% complement deficiencies. All countries that participated in the first publication in 1998 reported an increase in registered primary immunodeficiency cases, ranging between 10 and 80%. A comparison of the estimated minimal incidence of X-linked agammaglobulinemia, chronic granulomatous disease, and severe combined immunodeficiency between the first report and the present one shows an increase in the reporting of these diseases in all countries. In this report, the estimated minimal incidence of chronic granulomatous disease was between 0.72 and 1.26 cases per 100,000 births in Argentina, Chile, Costa Rica, and Uruguay and the incidence of severe combined immunodeficiency was 1.28 and 3.79 per 100,000 births in Chile and Costa Rica, respectively. However, these diseases are underreported in other participating countries. In addition to a better diagnosis of primary immunodeficiency diseases, more work on improving the registration of patients by each participating country and by countries that have not yet joined LAGID is still needed.

The majority of children with Down syndrome (DS) tend to have frequent bacterial infections including recurrent respiratory infections. Our objective was to evaluate the production of antibodies to pneumococcal polysaccharide antigens after active immunization in DS subjects. IgG antibodies to pneumococcal serotypes (1, 3, 6B, 9V, and 14) were measured before and 6 weeks after immunization with a 23-valent pneumococcal vaccine (Pneumo23, Pasteur-Merrieux) in 6- to 13-year-old DS children (N = 17) and in aged-matched normal controls (N = 30). An adequate response was defined as a 4-fold increase over baseline or a post-immunization level of specific pneumococcal serotype antibodyor = 1.3 microg/mL. After immunization, all DS children had an increase in post-immunization levels against all serotypes analyzed. A 4-fold or more increase was observed in all DS children concerning serotypes 1 and 14, in 90% of subjects for serotypes 3 and 9V, and in 65% for serotype 6B. Regarding this increase, 8 of the 17 DS children had an adequate response to all serotypes analyzed, 8/17 patients to 4 serotypes and 1/17 to 3 serotypes. However, when we compared post-immunization levels between DS children and controls, we observed lower levels in the former group (P0.05) for all serotypes except serotype 3. We conclude that pneumococcal polysaccharide immunization could be beneficial for these DS children.

OBJETIVO: Estudar a produção de anticorpos a antígenos polissacarídicos em pacientes com ataxia-telangiectasia CASUÍSTICA E MÉTODO: Utilizando a técnica de ELISA, determinamos os níveis de IgG aos sorotipos 1, 3, 5, 6B, 9V e 14 do pneumococo em 14 pacientes com ataxia-telangiectasia, antes e após a imunização com a vacina pneumocócica 23-valente. Resposta adequada a cada sorotipo foi definida como IgG > 1,3 µg/ml ou o incremento de quatro vezes dos níveis pós em relação aos pré-imunização. RESULTADOS: Seis pacientes (43%) não responderam a todos os sorotipos analisados, quatro a apenas um sorotipo, um paciente a dois, dois a três e apenas um paciente a quatro dos seis sorotipos analisados. Nenhum paciente apresentou resposta adequada a todos os sorotipos testados. Os níveis de IgG ao pneumococo pós-imunização foram superiores aos pré-imunização para todos os sorotipos testados, exceto o 3. Apesar disso, os valores médios pós-imunização foram inferiores a 1,3 µg/ml para todos os sorotipos analisados, exceto o 14. A média de incremento da resposta foi inferior a quatro para todos os sorotipos analisados. CONCLUSÃO: Nossos resultados sugerem que pacientes com ataxia-telangiectasia têm grande risco de apresentar resposta inadequada ao pneumococo, o que pode ser uma das causas das infecções sinopulmonares de repetição. OBJECTIVE: To analyze the production of antibodies to polysaccharide antigens in patients with ataxia-telangiectasia. PATIENTS AND METHODS: We used the ELISA technique to measure the levels of IgG antibodies to serotypes 1, 3, 5, 6B, 9V and 14 of Streptococcus pneumoniae in 14 patients with ataxia-telangiectasia before and after immunization with 23-valent polysaccharide vaccine. Adequate response to individual polysaccharide can be defined as a postimmunization antibody titer equal to or greater than 1.3 µg/ml or as a minimum fourfold increase over the baseline (preimmunization) value. RESULTS: Six (43%) patients showed an absent response to all serotypes analyzed. Four patients showed adequate response to only one serotype, one patient to two serotypes, two patients to three serotypes and only one patient to four out of six serotypes analyzed. No patient had adequate response to all serotypes tested. Postimmunization pneumococcus IgG levels were higher than preimmunization levels to all serotypes analyzed, except for serotype 3. In spite of this, the mean postimmunization levels were lower than 1.3 µg/ml in all serotypes, except for serotype 14. Mean increment was less than four in all serotypes analyzed. CONCLUSION: Our results suggest that patients with ataxia-telangiectasia are at a high risk of having an impaired response to pneumococcus, which may be one of the causes of recurrent sinopulmonary infections in these patients.

Sixty patients (16 children, 44 adults) participated in the study aiming at evaluating: (i) IgG levels when switching patients from intravenous IgG (IVIG) infusions in hospital to subcutaneous (SCIG) self-infusions at home using the same cumulative monthly dose, (ii) protections against infections, and (iii) safety of a new, ready-to-use 16% IgG preparation. All children and 33 adults had received IVIG therapy for >6 months at enrolment. Ten adults who had been on SCIG therapy for many years served as controls. Mean serum IgG trough levels increased in the pre-IVIG children from 7.8 to 9.2 g/L (non-inferiority: p < 0.001) and in the adults from 8.6 to 8.9 g/L (non-inferiority: p < 0.001). Totally 114 respiratory tract infections occurred, 90% of them mild. One serious bacterial infection (pneumonia) was reported for one adult. The annualized rate of serious infections was 0.04 episodes/patient. In total 2297 infusions were given and 28 (1%) systemic adverse reactions occurred, none of them severe. Local tissue reactions declined over time, this being particularly distinct after 8 to 10 weeks. In conclusion, the SCIG administration route was safe. High IgG levels were easily maintained resulting in a very good protection against infections.