Search

BackgroundLupus pathogenesis is mainly ascribed to increased production and/or impaired clearance of dead cell debris. Although self-reactive T and B lymphocytes are critically linked to lupus development, neutrophils, monocytes, and natural killer (NK) cells have also been implicated. This study assessed apoptosis-related protein expressions in NK cells of patients with juvenile-onset systemic lupus erythematosus (jSLE) and relations to disease activity parameters, nephritis, and neuropsychiatric involvement.MethodsThirty-six patients with jSLE, 13 juvenile dermatomyositis (JDM) inflammatory controls, and nine healthy controls had Fas, FasL, TRAIL, TNFR1, Bcl-2, Bax, Bim, and caspase-3 expressions in NK cells (CD3−CD16+CD56+) simultaneously determined by flow cytometry. Disease activity parameters included Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score, erythrocyte sedimentation rate, C-reactive protein level, anti-double strain DNA antibody level, complement fractions C3 and C4 levels.ResultsPatients with jSLE had a profile of significantly reduced expression of TRAIL, Bcl-2, and TNFR1 proteins in NK cells when compared to healthy controls. Similar profile was observed in patients with jSLE with active disease, positive anti-dsDNA, nephritis, and without neuropsychiatric involvement. Patients with jSLE with positive anti-dsDNA also had reduced expression of Bax in NK cells when compared healthy controls and to those with negative anti-dsDNA. Yet, patients with jSLE with negative anti-dsDNA had reduced mean fluorescence intensity (MFI) of Bim in NK cells compared to healthy controls. Patients with jSLE with nephritis also had reduced MFI of Fas in NK cells when compared to those without nephritis. In addition, in patients with jSLE, the proportion of FasL-expressing NK cells directly correlated with the SLEDAI-2K score (rs = 0.6, p = 0.002) and inversely correlated with the C3 levels (rs = −0.5, p = 0.007). Moreover, patients with jSLE had increased NK cell percentage and caspase-3 protein expression in NK cells when compared to JDM controls.ConclusionThis study extends to NK cells an altered profile of TRAIL, Bcl-2, TNFR1, Fas, FasL, Bax, Bim, and caspase-3 proteins in patients with jSLE, particularly in those with active disease, positive anti-dsDNA, nephritis, and without neuropsychiatric involvement. This change in apoptosis-related protein expressions may contribute to the defective functions of NK cells and, consequently, to lupus development. The full clarification of the role of NK cells in jSLE pathogenesis may pave the way for new therapies like those of NK cell–based.

Abstract We describe the first cases of germline biallelic null mutations in ARPC5, part of the Arp2/3 actin nucleator complex, in two unrelated patients presenting with recurrent and severe infections, early-onset autoimmunity, inflammation, and dysmorphisms. This defect compromises multiple cell lineages and functions, and when protein expression is reestablished in-vitro, the Arp2/3 complex conformation and functions are rescued. As part of the pathophysiological evaluation, we also show that interleukin (IL)−6 signaling is distinctively impacted in this syndrome. Disruption of IL-6 classical but not trans-signaling highlights their differential roles in the disease and offers perspectives for therapeutic molecular targets.

ObjectivesTo prospectively assess health-related quality of life (HRQoL), global functionality, and disability in primary caregivers of surviving children and adolescents after COVID-19.MethodsA longitudinal observational study was carried out on primary caregivers of surviving pediatric post-COVID-19 patients (n = 51) and subjects without COVID-19 (n = 60). EuroQol five-dimension five-level questionnaire (EQ-5D-5L) and 12-question WHO Disability Assessment Schedule 2.0 (WHODAS 2.0) were answered for both groups. The univariate regression analysis was carried out using SPSS (v 20) and significance was established at 5%.ResultsThe median duration between COVID-19 diagnosis in children and adolescents and longitudinal follow-up visits was 4.4 months (0.8–10.7). The median age of children and adolescents caregivers with laboratory-confirmed COVID-19 was similar to primary caregivers of subjects without laboratory-confirmed COVID-19 [43.2 (31.6–60.9) vs. 41.5 (21.6–54.8) years, p = 0.08], as well as similar female sex (p = 1.00), level of schooling (p = 0.11), social assistance program (p = 0.28), family income/month U$ (p = 0.25) and the number of household’s members in the residence (p = 0.68). The frequency of slight to extreme problems (level ≥ 2) of the pain/discomfort domain according to EQ-5D-5L score was significantly higher in the former group [74% vs. 52.5%, p = 0.03, OR = 2.57 (1.14–5.96)]. The frequency of disability according to WHODAS 2.0 total score was similar to those without disability and unknown (p = 0.79); however, with a very high disability in both groups (72.5% and 78.3%). Further analysis of primary caregivers of children and adolescents with post-COVID-19 condition (PCC) [n = 12/51 (23%)] compared to those without PCC [n = 39/51(77%)] revealed no differences between demographic data, EQ-5D-5L and WHODAS 2.0 scores in both groups (p > 0.05).ConclusionWe longitudinally demonstrated that pain/discomfort were predominantly reported in approximately 75% of primary caregiver of COVID-19 patients, with high disability in approximately three-quarters of both caregiver groups. These data emphasized the prospective and systematic caregiver burden evaluation relevance of pediatric COVID-19.

Abstract We investigated the anti-SARS-CoV-2 post-vaccine response through serum and salivary antibodies, serum antibody neutralizing activity and cellular immune response in samples from health care workers who were immunized with two doses of an inactivated virus-based vaccine (CoronaVac) who had or did not have COVID-19 previously. IgA and IgG antibodies directed at the spike protein were analysed in samples of saliva and/or serum by ELISA and/or chemiluminescence assays; the neutralizing activity of serum antibodies against reference strain B, Gamma and Delta SARS-CoV-2 variants were evaluated using a virus neutralization test and SARS-CoV-2 reactive interferon-gamma T-cell were analysed by flow cytometry. CoronaVac was able to induce serum and salivary IgG anti-spike antibodies and IFN-γ producing T cells in most individuals who had recovered from COVID-19 and/or were vaccinated. Virus neutralizing activity was observed against the ancestral strain, with a reduced response against the variants. Vaccinated individuals who had previous COVID-19 presented higher responses than vaccinated individuals for all variables analysed. Our study provides evidence that the CoronaVac vaccine was able to induce the production of specific serum and saliva antibodies, serum virus neutralizing activity and cellular immune response, which were increased in previously COVID-19-infected individuals compared to uninfected individuals.

Resumo Fundamento Algumas síndromes têm características específicas e facilmente reconhecíveis, enquanto outras podem ser mais complexas de se identificar e podem apresentar diferentes manifestações fenotípicas, por exemplo. Um diagnóstico etiológico é importante para entender a natureza da doença, para estabelecer o prognóstico e para começar o tratamento, permitindo a inclusão de pacientes na sociedade e reduzindo o custo financeiro dessas doenças. Objetivo A proposta inicial deste estudo foi a triagem citogenética para detectar a síndrome de deleção 22q11.2 (SD22q11.2) em recém-nascidos e crianças com doença cardíaca congênita utilizando a técnica da amplificação multiplex de sondas dependente de ligação (MLPA). Assim, por meio da pesquisa, outras mudanças genômicas foram identificadas nesses pacientes cardíacos. Nosso objetivo se estendeu a investigar essas outras mudanças citogenéticas. Métodos Investigamos 118 recém-nascidos com doenças cardíacas congênitas nascidos consecutivamente durante um ano, utilizando a técnica da MLPA. Resultados A técnica da MLPA permitiu a detecção da SD22q11.2 em 10/118 pacientes (8,5%). Outras alterações genômicas foram identificadas em 6/118 pacientes (5%): 1p36 del, 8p23 del (2 casos), 7q dup, 12 dup e 8q24 dup. Conclusão Este estudo ressalta a relevância da detecção de alterações genômicas que estão presentes em recém-nascidos e crianças com doenças cardíacas congênitas por meio de ferramentas citogenômicas.

Resumo Fundamento A pandemia da COVID-19 representa uma enorme carga para o sistema de saúde do mundo. Apesar de pacientes pediátricos terem sido relativamente poupados em comparação a adultos, estudos recentes mostraram um número crescente de pacientes críticos com Síndrome Inflamatória Multisistêmica Pediátrica (SIM-P) com disfunção cardiovascular importante. No entanto, pouco se conhece a respeito da relação entre anormalidades cardíacas e biomarcadores inflamatórios e de coagulação. Objetivos Investigar anormalidades ecocardiográficas em pacientes pediátricos com COVID-19 admitidos em um hospital terciário. Métodos Este foi um estudo longitudinal retrospectivo, baseado na revisão de prontuários médicos e ecocardiogramas de pacientes (0-19 anos) admitidos em um hospital terciário entre 30 de março e 30 de junho de 2020. Para a análise estatística, o nível de significância foi estabelecido em 5% (p+2,5). Anormalidades ecocardiográficas foram significativamente associadas com SIM-P, admissão na unidade de terapia intensiva pediátrica, suporte ventilatório/vasoativo, e morte ( p

In this article we revised the literature on Inborn Errors of Immunity (IEI) keeping our focus on those diseases presenting with intrauterine or perinatal clinical manifestations. We opted to describe our findings according to the IEI categories established by the International Union of Immunological Societies, predominantly addressing the immunological features of each condition or group of diseases. The main finding is that such precocious manifestations are largely concentrated in the group of primary immune regulatory disorders (PIRDs) and not in the group of classical immunodeficiencies. The IEI categories with higher number of immunological manifestations in utero or in perinatal period are: (i) diseases of immune dysregulation (HLH, IPEX and other Tregopathies, autosomal recessive ALPS with complete lack of FAS protein expression) and (ii) autoinflammatory diseases (NOMID/CINCA, DIRA and some interferonopathies, such as Aicardi-Goutières syndrome, AGS, and USP18 deficiency). Regarding the other IEI categories, some patients with Omenn syndrome (an atypical form of SCID), and a few X-linked CGD patients present with clinical manifestations at birth associated to immune dysregulation. The most frequent clinical features were hydrops fetalis, intrauterine growth retardation leading to fetal loss, stillbirths, and prematurity, as in HLH and IPEX. Additionally, pseudo-TORCH syndrome was observed in AGS and in USP18 deficiency. The main goal of our review was to contribute to increasing the medical awareness of IEI with intrauterine and perinatal onset, which has obvious implications for diagnosis, treatment, and genetic counseling.

Objectives: To evaluate mortality in adolescents and young adult patients with chronic diseases followed in a Latin American tertiary hospital. Methods: A cross‐sectional retrospective study was performed in a tertiary/academic hospital in the state of São Paulo, Brazil. Death occurred in 529/2850 (18.5%) adolescents and young adult patients with chronic diseases, and 25/529 (4.7%) were excluded due to incomplete medical charts. Therefore, 504 deaths were evaluated. Results: Deaths occurred in 316/504 (63%) of early adolescent patients and in 188/504 (37%) of late adolescent/young adult patients. Further comparisons between early adolescents (n = 316) and late adolescent/young adult patients (n = 188) with pediatric chronic diseases at the last hospitalization showed that the median disease duration (22.0 [0–173] vs. 43.0 [0–227] months, p

Inborn errors of immunity (IEI), which were previously termed primary immunodeficiency diseases, represent a large and growing heterogeneous group of diseases that are mostly monogenic. In addition to increased susceptibility to infections, other clinical phenotypes have recently been associated with IEI, such as autoimmune disorders, severe allergies, autoinflammatory disorders, benign lymphoproliferative diseases, and malignant manifestations. The IUIS 2019 classification comprises 430 distinct defects that, although rare individually, represent a group affecting a significant number of patients, with an overall prevalence of 1:1,200-2,000 in the general population. Early IEI diagnosis is critical for appropriate therapy and genetic counseling, however, this process is deeply dependent on accurate laboratory tests. Despite the striking importance of laboratory data for clinical immunologists, several IEI-relevant immunoassays still lack standardization, including standardized protocols, reference materials, and external quality assessment programs. Moreover, well-established reference values mostly remain to be determined, especially for early ages, when the most severe conditions manifest and diagnosis is critical for patient survival. In this article, we intend to approach the issue of standardization and quality control of the nonfunctional diagnostic tests used for IEI, focusing on those frequently utilized in clinical practice. Herein, we will focus on discussing the issues of nonfunctional immunoassays (flow cytometry, enzyme-linked immunosorbent assays, and turbidimetry/nephelometry, among others), as defined by the pure quantification of proteins or cell subsets without cell activation or cell culture-based methods.

Background and AimsCongenital heart diseases (CHDs) are diagnosed in approximately 9 in 1,000 newborns, and early cardiac corrective surgery often requires partial or complete thymectomy. As the long-term effect of early thymectomy on the subsequent development of the immune system in humans has not been completely elucidated, the present study aimed to evaluate the effects of thymus removal on the functional capacity of the immune system after different periods.MethodsA systematic review of the literature was performed using MEDLINE, EMBASE, LILACS and Scopus. The inclusion criteria were original studies that analyzed any component of the immune system in patients with CHD who had undergone thymectomy during cardiac surgery in the first years of life. The results were evaluated for the quality of evidence.ResultsTwenty-three studies were selected and showed that patients who underwent a thymectomy in the first years of life tended to exhibit important alterations in the T cell compartment, such as fewer total T cells, CD4+, CD8+, naïve and CD31+ T cells, lower TRECs, decreased diversity of the TCR repertoire and higher peripheral proliferation (increased Ki-67 expression) than controls. However, the numbers of memory T cells and Treg cells differed across the selected studies.ConclusionsEarly thymectomy, either partial or complete, may be associated with a reduction in many T cell subpopulations and TCR diversity, and these alterations may persist during long-term follow-up. Alternative solutions should be studied, either in the operative technique with partial preservation of the thymus or through the autograft of fragments of the gland.Systematic Review RegistrationProspero [157188].

OBJECTIVES: To compare demographic/clinical/laboratory/treatments and outcomes among children and adolescents with laboratory-confirmed coronavirus disease 2019 (COVID-19). METHODS: This was a cross-sectional study that included patients diagnosed with pediatric COVID-19 (aged

OBJECTIVES: To prospectively evaluate demographic, anthropometric and health-related quality of life (HRQoL) in pediatric patients with laboratory-confirmed coronavirus disease 2019 (COVID-19) METHODS: This was a longitudinal observational study of surviving pediatric post-COVID-19 patients (n=53) and pediatric subjects without laboratory-confirmed COVID-19 included as controls (n=52) was performed. RESULTS: The median duration between COVID-19 diagnosis (n=53) and follow-up was 4.4 months (0.8-10.7). Twenty-three of 53 (43%) patients reported at least one persistent symptom at the longitudinal follow-up visit and 12/53 (23%) had long COVID-19, with at least one symptom lasting for >12 weeks. The most frequently reported symptoms at the longitudinal follow-up visit were headache (19%), severe recurrent headache (9%), tiredness (9%), dyspnea (8%), and concentration difficulty (4%). At the longitudinal follow-up visit, the frequencies of anemia (11% versus 0%, p=0.030), lymphopenia (42% versus 18%, p=0.020), C-reactive protein level of >30 mg/L (35% versus 0%, p=0.0001), and D-dimer level of >1000 ng/mL (43% versus 6%, p=0.0004) significantly reduced compared with baseline values. Chest X-ray abnormalities (11% versus 2%, p=0.178) and cardiac alterations on echocardiogram (33% versus 22%, p=0.462) were similar at both visits. Comparison of characteristic data between patients with COVID-19 at the longitudinal follow-up visit and controls showed similar age (p=0.962), proportion of male sex (p=0.907), ethnicity (p=0.566), family minimum monthly wage (p=0.664), body mass index (p=0.601), and pediatric pre-existing chronic conditions (p=1.000). The Pediatric Quality of Live Inventory 4.0 scores, median physical score (69 [0-100] versus 81 [34-100], p=0.012), and school score (60 [15-100] versus 70 [15-95], p=0.028) were significantly lower in pediatric patients with COVID-19 at the longitudinal follow-up visit than in controls. CONCLUSIONS: Pediatric patients with COVID-19 showed a longitudinal impact on HRQoL parameters, particularly in physical/school domains, reinforcing the need for a prospective multidisciplinary approach for these patients. These data highlight the importance of closer monitoring of children and adolescents by the clinical team after COVID-19.

Background: COVID-19 in children is usually mild or asymptomatic, but severe and fatal paediatric cases have been described. The pathology of COVID-19 in children is not known; the proposed pathogenesis for severe cases includes immune-mediated mechanisms or the direct effect of SARS-CoV-2 on tissues. We describe the autopsy findings in five cases of paediatric COVID-19 and provide mechanistic insight into the mechanisms involved in the pathogenesis of the disease. Methods: Children and adolescents who died with COVID-19 between March 18 and August 15, 2020 were autopsied with a minimally invasive method. Tissue samples from all vital organs were analysed by histology, electron microscopy (EM), reverse-transcription polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC). Findings: Five patients were included, one male and four female, aged 7 months to 15 years. Two patients had severe diseases before SARS-CoV-2 infection: adrenal carcinoma and Edwards syndrome. Three patients were previously healthy and had multisystem inflammatory syndrome in children (MIS-C) with distinct clinical presentations: myocarditis, colitis, and acute encephalopathy with status epilepticus. Autopsy findings varied amongst patients and included mild to severe COVID-19 pneumonia, pulmonary microthrombosis, cerebral oedema with reactive gliosis, myocarditis, intestinal inflammation, and haemophagocytosis. SARS-CoV-2 was detected in all patients in lungs, heart and kidneys by at least one method (RT-PCR, IHC or EM), and in endothelial cells from heart and brain in two patients with MIS-C (IHC). In addition, we show for the first time the presence of SARS-CoV-2 in the brain tissue of a child with MIS-C with acute encephalopathy, and in the intestinal tissue of a child with acute colitis. Interpretation: SARS-CoV-2 can infect several cell and tissue types in paediatric patients, and the target organ for the clinical manifestation varies amongst individuals. Two major patterns of severe COVID-19 were observed: a primarily pulmonary disease, with severe acute respiratory disease and diffuse alveolar damage, or a multisystem inflammatory syndrome with the involvement of several organs. The presence of SARS-CoV-2 in several organs, associated with cellular ultrastructural changes, reinforces the hypothesis that a direct effect of SARS-CoV-2 on tissues is involved in the pathogenesis of MIS-C. Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Bill and Melinda Gates Foundation.

IPEX is one of the few Inborn Errors of Immunity that may manifest in the fetal period, and its intrauterine forms certainly represent the earliest human autoimmune diseases. Here, we review the clinical, histopathologic, and genetic findings from 21 individuals in 11 unrelated families, with nine different mutations, described as cases of intrauterine IPEX. Recurrent male fetal death (multigenerational in five families) due to hydrops in the midsemester of pregnancy was the commonest presentation (13/21). Noteworthy, in the affected families, there were only fetal- or perinatal-onset cases, with no affected individuals presenting milder forms with later-life manifestation. Most alive births were preterm (5/6). Skin desquamation and intrauterine growth restriction were observed in part of the cases. Fetal ultrasonography showed hyperechoic bowel or dilated bowel loops in the five cases with available imaging data. Histopathology showed multi-visceral infiltrates with T lymphocytes and other cells, including eosinophils, the pancreas being affected in most of the cases (11/21) and as early as at 18 weeks of gestational age. Regarding the nine FOXP3 mutations found in these cases, six determine protein truncation and three predictably impair protein function. Having found distinct presentations for the same FOXP3 mutation in different families, we resorted to the mouse system and showed that the scurfy mutation also shows divergent severity of phenotype and age of death in C57BL/6 and BALB/c backgrounds. We also reviewed age-of-onset data from other monogenic Tregopathies leading to IPEX-like phenotypes. In monogenic IPEX-like syndromes, the intrauterine onset was only observed in two kindreds with IL2RB mutations, with two stillbirths and two premature neonates who did not survive. In conclusion, intrauterine IPEX cases seem to constitute a particular IPEX subgroup, certainly with the most severe clinical presentation, although no strict mutation-phenotype correlations could be drawn for these cases.

ABSTRACT Objective: To assess personal, professional, medical, and scientific educational characteristics and issues reported by pediatricians. Methods: Cross-sectional study based on an online survey including 614 pediatricians who graduated in the last 15 years at a University Pediatric Department in Brazil. Results: The response rate was 331/614(54%). The majority were females (82%), the median age was 33 years (27-40) and median years of pediatric practice was 5 (1-13). High workload (>60 hours/week) occurred in 25% and 47% earned ≥15 minimum wages/month. The most work-related issues reported were long working hours, poor social life and a sedentary lifestyle (>50%). Pediatricians were further divided into two groups, according to years of pediatric clinical practice: group 1 (≤5 years) and group 2 (>5 years). The median of overall satisfaction with pediatric residency [8(0-10) vs. 9 (4-10); p=0.002] was significantly reduced in group 1. The frequencies of workload >60 hours, work on pediatric ward and pediatric intensive care were significantly higher in the first group (p5 years). The overall satisfaction with pediatric residency was good, however, reduced in very early career pediatricians.

OBJECTIVE: This study aimed to determine the personal and professional characteristics, and the physical, psychiatric/psychological, and professional issues that exist among master’s-, doctoral-, and post-doctoral-level health professionals. METHODS: A cross-sectional, online, self-reported survey of 452 postgraduates who completed master’s, doctoral, or post-doctoral degrees in one graduate program in pediatrics in São Paulo, Brazil, was conducted. RESULTS: The response rate was 47% (211/453). The majority of participants were women (78%) and physicians (74%), and the median age was 47 years (28-71). Master’s, doctoral, and post-doctoral degrees were reported by 73%, 53%, and 3%, respectively. High workload (>40 hours/week) occurred in 59%, and 45% earned ≥15 minimum wages/month. At least one participation in scientific meeting in the past year was reported by 91%, and 79% had published their research. Thirty-nine percent served as a member of a faculty of an institution of higher learning. The data were analyzed by two age groups: participants aged ≤48 years (group 1) and participants aged >48 years (group 2). The median rating of overall satisfaction with the profession in the past year [8 (0-10) vs. 9 (1-10), p=0.0113]; workload >40 hours/week (53% vs. 68%, p=0.034); and ≥15 minimum wages/month (37% vs. 56%, p=0.0083) were significantly lower in group 1. Further analysis by gender revealed that the median rating of overall satisfaction with the profession in the past year [8 (0-10) vs. 9 (3-10), p=0.0015], workload >40 hours/week (53% vs. 83%, p=0.0002), and ≥15 minimum wages/month (37% vs. 74%, p=0.0001) were significantly lower in women compared with men. The median rating of overall satisfaction with the mentorship supervision provided was significantly higher among the women 10 (5-10) vs. 10 (2-10), p=0.0324]. CONCLUSIONS: The majority of master’s-, doctoral-, and post-doctoral-level health professionals were women and physicians, and had published their thesis. Younger postgraduates and women reported low salaries, less likelihood of working >40 hours/week, and less overall satisfaction with their profession. Further longitudinal and qualitative studies are warranted to assess career trajectories after graduation.

Objective: To describe the characteristics of children and adolescentes with chronic diseases of outpatient clinics at a tertiary university hospital. Methods: A cross‐sectional study was performed with 16,237 patients with chronic diseases followed‐up in one year. The data were collected through the electronic system, according to the number of physician appointments in 23 pediatric specialties. Patients were divided in two groups: children (0–9 years) and adolescents (10–19 years). Early (10–14 years) and late (15–19 years) adolescent groups were also analyzed. Results: Of the total sample, 56% were children and 46% were adolescents. The frequencies of following pediatric specialties were significantly higher in adolescents when compared with children: cardiology, endocrinology, hematology, nephrology/renal transplantation, neurology, nutrology, oncology, palliative and pain care, psychiatry, and rheumatology (p

ABSTRACT Objective: To assess demographic data and characteristics of children and adolescents with pediatric chronic diseases (PCD), according to the number of specialties/patient. Methods: We performed a cross-sectional study with 16,237 PCD patients at outpatient clinics in one year. Data were analyzed by an electronic data system, according to the number of physician appointments for PCD. This study assessed: demographic data, follow-up characteristics, types of medical specialty, diagnosis (International Statistical Classification of Diseases and Related Health Problems - ICD-10), number of day hospital clinic visits, and acute complications. Results: Patients followed by ≥3 specialties simultaneously showed a significantly higher duration of follow-up compared to those followed by ≤2 specialties [2.1 (0.4-16.4) vs. 1.4 (0.1-16.2) years; p

Abstract Objective The potential association of mannose binding lectin (MBL) deficiency and systemic lupus erythematosus (SLE) has been investigated in several studies, but results have been mixed. One explanation for the conflicting results could be differences in ethnic background of study subjects. In this study we investigated the association of MBL deficiency and SLE in a large cohort of Brazilian SLE patients and controls. Methods Serum MBL and Complement levels were determined for 286 Brazilian adult SLE patients and 301 healthy Brazilian adults as controls. MBL deficiency was classified as mild (

OBJECTIVES: The aim of this study is to present a survey of vulnerabilities and to suggest approaches for the treatment of rare diseases according to the perceptions of a group of affected individuals, patient association representatives and health care professionals. METHODS: The focus group technique was used in interviews with patients and primary caregivers, patient support groups/non-governmental organizations, primary health care professionals and physician specialists. RESULTS: The transcript analysis focused on thematic units, which were tailored to each group and allowed comparisons in search of concordant views. Unanimity was observed in relation to the physical, emotional and social damage to the life standards of the affected individuals and their families as a result of illness. The Brazilian health system was unanimously classified as inadequate to respond to the needs of patients with rare diseases, and this inadequacy led to unpleasant experiences, such as the seemingly endless referrals among health services to reach a final diagnosis and develop a treatment plan. CONCLUSIONS: The complex set of health system requirements necessary to support the care of patients with rare diseases represents an obstacle to successfully meeting the needs of patients and their families. Therefore, it is important to develop specific public policies to create referral services, guarantee access to appropriate therapeutic modalities and incorporate technologies that promote research for developing new, affordable therapies.

Introdução: As manifestações clínicas da deficiência de imunoglobulina A (DIgA) incluem infecções recorrentes, atopia e doenças autoimunes. No entanto, para o nosso conhecimento, as avaliações concomitantes de doenças autoimunes e autoanticorpos em uma coorte de pacientes com DIgA com idade atual > 10 anos e seus parentes não foram feitas. Objetivos: Avaliar doenças autoimunes e presença de autoanticorpos em pacientes com DIgA e seus parentes de primeiro grau. Métodos: Estudo transversal feito em 34 pacientes com DIgA (idade atual > 10 anos) e em seus parentes de primeiro grau. Todos foram acompanhados em um centro terciário brasileiro para imunodeficiência primária: 27 crianças/adolescentes e sete de seus parentes de primeiro grau com diagnóstico tardio de DIgA. Doenças autoimunes e autoanticorpos (anticorpos antinucleares, fator reumatoide e antitireoglobulina, antitiroperoxidase e anticorpos antiendomísio da classe IgA) também foram avaliadas. Resultados: Doenças autoimunes (n = 14) e/ou autoanticorpos (n = 10, quatro deles com autoanticorpos isolados) foram observadas em 18/34 (53%) dos pacientes e seus parentes. As doenças autoimunes mais comuns encontradas foram tireoidite (18%), artrite crônica (12%) e doença celíaca (6%). Os autoanticorpos mais frequentes foram anticorpos antinucleares (2%), antitireoglobulina e/ou antitireoperoxidase (24%). Nenhuma diferença significativa foi observada no sexo feminino, idade no momento do diagnóstico e idade atual em pacientes com DIgA com e sem doenças autoimunes e/ou presença de autoanticorpos (p > 0,05). As frequências de imunodeficiência de primárias na família, autoimunidade em família, atopia e infecções recorrentes foram semelhantes em ambos os grupos (p> 0,05). Conclusão: Doenças autoimunes e autoanticorpos foram observadas em pacientes com DIgA durante o acompanhamento, o que reforça a necessidade de um acompanhamento rigoroso e contínuo durante a adolescência e a idade adulta.

OBJECTIVE: To perform a molecular characterization of the C1q, C2 and C4 genes in patients with juvenile systemic lupus erythematosus. METHODS: Patient 1 (P1) had undetectable C1q, patient 2 (P2) and patient 3 (P3) had decreased C2 and patient 4 (P4) had decreased C4 levels. All exons and non-coding regions of the C1q and C2 genes were sequenced. Mononuclear cells were cultured and stimulated with interferon gamma to evaluate C1q, C2 and C4 mRNA expression by quantitative real-time polymerase chain reaction. RESULTS: C1q sequencing revealed heterozygous silent mutations in the A (c.276 A>G Gly) and C (c.126 C>T Pro) chains, as well as a homozygous single-base change in the 3′ non-coding region of the B chain (c*78 A>G). C1qA mRNA expression without interferon was decreased compared with that of healthy controls (p

Background: To alert for the diagnosis of the 22q11.2 deletion syndrome (22q11.2DS) in patients with congenital heart disease (CHD). Objective: To describe the main CHDs, as well as phenotypic, metabolic and immunological findings in a series of 60 patients diagnosed with 22q11.2DS. Methods: The study included 60 patients with 22q11.2DS evaluated between 2007 and 2013 (M:F=1.3, age range 14 days to 20 years and 3 months) at a pediatric reference center for primary immunodeficiencies. The diagnosis was established by detection of the 22q11.2 microdeletion using FISH (n = 18) and/or MLPA (n = 42), in association with clinical and laboratory information. Associated CHDs, progression of phenotypic facial features, hypocalcemia and immunological changes were analyzed. Results: CHDs were detected in 77% of the patients and the most frequent type was tetralogy of Fallot (38.3%). Surgical correction of CHD was performed in 34 patients. Craniofacial dysmorphisms were detected in 41 patients: elongated face (60%) and/or elongated nose (53.3%), narrow palpebral fissure (50%), dysplastic, overfolded ears (48.3%), thin lips (41.6%), elongated fingers (38.3%) and short stature (36.6%). Hypocalcemia was detected in 64.2% and decreased parathyroid hormone (PTH) level in 25.9%. Decrease in total lymphocytes, CD4 and CD8 counts were present in 40%, 53.3% and 33.3%, respectively. Hypogammaglobulinemia was detected in one patient and decreased concentrations of immunoglobulin M (IgM) in two other patients. Conclusion: Suspicion for 22q11.2DS should be raised in all patients with CHD associated with hypocalcemia and/or facial dysmorphisms, considering that many of these changes may evolve with age. The 22q11.2 microdeletion should be confirmed by molecular testing in all patients.

Objective:To analyze toll-like receptor (TLR)-2 and TLR-4 expression in monocytes of newborns with late-onset sepsis.Methods:This prospective study included 27 full-term newborns aged 8 to 29 days, with clinical and laboratory diagnosis of late-onset sepsis. Ten newborns (37%) had positive cultures. Cytokines were measured by cytometric bead array in peripheral blood, while TLR-2, TLR-4 expression, and median fluorescence intensity (MFI) were determined by immunophenotyping peripheral whole blood monocytes, and were analyzed with a BD FACSDiva flow cytometer (Becton, Dickinson and Company, USA). A comparison was performed with healthy adults.Results:Microorganisms were identified in 37% of these septic newborns, and all of them had high levels of pro-inflammatory cytokines (IL-8, IL-6, IL-1β) and anti-inflammatory cytokine (IL-10) corroborating the inflammatory/septic process. In monocytes, the frequency of TLR-4 expression was higher in infected newborns (p = 0.01).Conclusion:This study investigated the innate immune response in septic newborns. Septic newborns that relied almost exclusively on the innate immune system showed little in vivo response at monocyte activation, suggesting impaired immune response and increased susceptibility to infection.

OBJETIVO: Avaliar a presença de anticorpos anti-C1q, anticromatina/nucleossomo e anti-DNA de duplo filamento (dsDNA) em pacientes com lúpus eritematoso sistêmico juvenil (LESJ) e controles. MÉTODOS: Foram analisados 67 pacientes com LESJ e 34 controles saudáveis para presença de anticorpos anti-C1q, anticromatina/nucleossomo e anti-dsDNA pelo método ELISA. Os níveis de C1q foram avaliados por imunodifusão radial. RESULTADOS: Na época, a média de idade era similar entre os pacientes com LESJ e os controles (14,6 ± 3,86 vs. 13,6 ± 2,93 anos; P = 0,14). Foram observadas frequências mais altas de anticorpos anti-C1q, anticromatina/nucleossomo e anti-dsDNA em pacientes com LESJ em relação aos controles (20% vs. 0%; P = 0,0037; 48% vs. 0%; P < 0,0001 e 69% vs. 3%; P < 0,0001, respectivamente). A mediana dos anticorpos anti-C1q, anticromatina/nucleossomo e anti-dsDNA também foi significativamente mais alta em pacientes com LESJ em relação aos controles [9,6 (5,5-127) vs. 7,5 (5-20) unidades, P = 0,0006; 18 (1,9-212) vs. 3,2 (1,7-17) unidades, P < 0,0001; e 111 UI/mL (6-741) vs. 14 (6-33) UI/mL, P < 0,0001, respectivamente]. A sensibilidade para os anticorpos anti-C1q, anticromatina/nucleossomo e anti-dsDNA foi: 21% (IC: 11-33), 49% (IC: 36-62) e 70% (IC: 57-81). A especificidade foi de 100% (IC: 88-100), 100% (88-100) e 97% (IC: 83-99), respectivamente. Foi observada uma correlação positiva entre os níveis de anti-dsDNA e tanto anticorpos anti-C1q (r = 0,51; IC: 0,29-0,68; P < 0,0001) como anticromatina/nucleossomo (r = 0,87; IC: 0,79-0,92; P < 0,0001). Foi observada uma correlação negativa entre os níveis de anti-C1q e C1q (r = -0,33; IC: -0,56-0,05; P = 0,018). A frequência de anti-dsDNA foi mais alta em pacientes com SLEDAI-2K > 1 (P = 0,0047), e não foram observadas diferenças nas frequências desses três autoanticorpos e nefrite (P > 0,05). CONCLUSÃO: Nosso estudo demonstrou elevada especificidade para diagnóstico de lúpus envolvendo os três autoanticorpos, especialmente anti-C1q e anticromatina/nucleossomo.OBJECTIVES: To evaluate the presence of anti-C1q, anti-chromatin/nucleosome and anti-double stranded DNA (dsDNA) antibodies in juvenile systemic lupus erythematosus (JSLE) and controls. METHODS: Sixty-seven JSLE and 34 healthy controls were analyzed for the presence of anti-C1q, anti-chromatin/nucleosome, and anti-dsDNA antibodies by ELISA. C1q levels were evaluated by radial immunodiffusion. RESULTS: The mean current age was similar in JSLE patients and controls (14.6 ± 3.86 vs. 13.6 ± 2.93 years, P = 0.14). Higher frequencies of anti-C1q, anti-chromatin/nucleossome, and anti-dsDNA antibodies were observed in JSLE compared to controls (20% vs. 0%, P = 0.0037; 48% vs. 0%, P < 0.0001 and 69% vs. 3%, P < 0.0001, respectively). The median of anti-C1q, anti-chromatin/nucleossome, and antidsDNA antibodies were also significantly higher in JSLE patients than in controls [9.6 (5.5-127) vs. 7.5 (5-20) units, P = 0.0006; 18 (1.9-212) vs. 3.2 (1.7-17) units, P < 0.0001; and 111 IU/mL (6-741) vs. 14 (6-33) IU/mL; P < 0.0001, respectively]. The sensitivity for anti-C1q, anti-chromatin/nucleosome, and anti-dsDNA antibodies was 21% (CI: 11-33), 49% (CI: 36-62), and 70% (CI: 57-81). The specificity was 100% (CI: 88-100), 100% (88-100), and 97% (CI: 83-99), respectively. A positive correlation was found between anti-dsDNA levels and both anti-C1q (r = 0.51; CI: 0.29-0.68; P < 0.0001) and anti-chromatin/nucleosome antibodies (r = 0.87; CI: 0.79-0.92; P < 0.0001) levels. A negative correlation was observed between anti-C1q and C1q levels (r = -0.33; CI: -0.56-0.05; P = 0.018). The frequency of anti-dsDNA was higher in patients with SLEDAI-2K >1 (P = 0.0047) and no differences were observed in the frequencies of these three autoantibodies and nephritis (P > 0.05). CONCLUSION: Our study demonstrated an elevated specificity for lupus diagnosis involving the three autoantibodies, especially anti-C1q and anti-chromatin/nucleosome.

OBJECTIVE: The aim of this study was to assess the IgE serum levels in juvenile systemic lupus erythematosus patients and to evaluate possible associations with clinical and laboratory features, disease activity and tissue damage. METHODS: The IgE serum concentrations in 69 consecutive juvenile systemic lupus erythematosus patients were determined by nephelometry. IgG, IgM and IgA concentrations were measured by immunoturbidimetry. All patients were negative for intestinal parasites. Statistical analysis methods included the Mann-Whitney, chi-square and Fisher's exact tests, as well as the Spearman rank correlation coefficient. RESULTS: Increased IgE concentrations above 100 IU/mL were observed in 31/69 (45%) juvenile systemic lupus erythematosus patients. The mean IgE concentration was 442.0 ± 163.4 IU/ml (range 3.5-9936.0 IU/ml). Fifteen of the 69 patients had atopic disease, nine patients had severe sepsis and 56 patients presented with nephritis. The mean IgE level in 54 juvenile systemic lupus erythematosus patients without atopic manifestations was 271.6 ± 699.5 IU/ml, and only nine of the 31 (29%) patients with high IgE levels had atopic disease. The IgE levels did not statistically differ with respect to the presence of atopic disease, severe sepsis, nephritis, disease activity, or tissue damage. Interestingly, IgE concentrations were inversely correlated with C4 levels (r = -0.25, p = 0.03) and with the SLICC/ACR-DI score (r = -0.34, p = 0.005). The IgE concentration was also found to be directly correlated with IgA levels (r = 0.52, p = 0.03). CONCLUSIONS: The present study demonstrated for the first time that juvenile systemic lupus erythematosus patients have increased IgE serum levels. This increase in IgE levels was not related to allergic or parasitic diseases. Our results are in line with the hypothesis that high IgE levels can be considered a marker of immune dysregulation.

OBJECTIVE: The establishment of the intestinal microbiota in newborns is a critical period with possible long-term consequences for human health. In this research, the development of the fecal microbiota of a group of exclusively breastfed neonates living in low socio-economic conditions in the city of São Paulo, Brazil, during the first month of life, was studied. METHODS: Fecal samples were collected from ten neonates on the second, seventh, and 30th days after birth. One of the neonates underwent antibiotic therapy. Molecular techniques were used for analysis; DNA was extracted from the samples, and 16S rRNA libraries were sequenced and phylogenetically analyzed after construction. A real-time polymerase chain reaction (PCR) was performed on the samples taken from the 30th day to amplify DNA from Bifidobacterium sp. RESULTS: The primary phylogenetic groups identified in the samples were Escherichia and Clostridium. Staphylococcus was identified at a low rate. Bifidobacterium sp. was detected in all of the samples collected on the 30th day. In the child who received antibiotics, a reduction in anaerobes and Escherichia, which was associated with an overgrowth of Klebsiella, was observed throughout the experimental period. CONCLUSION: The observed pattern of Escherichia predominance and reduced Staphylococcus colonization is in contrast with the patterns observed in neonates living in developed countries.

OBJETIVO: Descrever as principais síndromes autoinflamatórias hereditárias na faixa etária pediátrica. FONTES DOS DADOS: Foi realizada uma revisão da literatura nas bases de dados PubMed e SciELO, utilizando as palavras-chave "síndromes autoinflamatórias” e "criança”, e incluindo referências bibliográficas relevantes. SÍNTESE DOS DADOS: As principais síndromes autoinflamatórias são causadas por defeitos monogênicos em proteínas da imunidade inata, sendo consideradas imunodeficiências primárias. Elas são caracterizadas clinicamente por sintomas inflamatórios sistêmicos recorrentes ou contínuos e devem ser diferenciadas das doenças infecciosas, autoimunes e outras imunodeficiências primárias. Nesta revisão, foram enfatizadas características epidemiológicas, manifestações clínicas, alterações laboratoriais, prognóstico e terapia das principais síndromes autoinflamatórias: febre familiar do Mediterrâneo; síndrome periódica associada ao receptor de fator de necrose tumoral; criopirinopatias; deficiência de mevalonato-quinase; artrite granulomatosa pediátrica; síndrome de pioderma gangrenoso, artrite piogênica e acne; síndrome de Majeed; e deficiência do antagonista do receptor de interleucina-1. As criopirinopatias discutidas foram: doença inflamatória multissistêmica de início neonatal ou síndrome neurológica, cutânea e articular crônica infantil, síndrome de Muckle-Wells e síndrome autoinflamatória familiar associada ao frio. CONCLUSÕES: É importante que o pediatra reconheça as síndromes autoinflamatórias hereditárias mais prevalentes, pois o encaminhamento ao reumatologista pediátrico pode permitir um diagnóstico precoce e uma instituição de tratamento adequado, possibilitando uma melhora da qualidade de vida dos pacientes.OBJECTIVE: To describe the most prevalent pediatric hereditary autoinflammatory syndromes. SOURCES: A review of the literature including relevant references from the PubMed and SciELO was carried out using the keywords autoinflammatory syndromes and child. SUMMARY OF THE FINDINGS: The hereditary autoinflammatory syndromes are caused by monogenic defects of innate immunity and are classified as primary immunodeficiencies. These syndromes are characterized by recurrent or persistent systemic inflammatory symptoms and must be distinguished from infectious diseases, autoimmune diseases, and other primary immunodeficiencies. This review describes the epidemiological, clinical and laboratory features, prognosis, and treatment of the main autoinflammatory syndromes, namely: familial Mediterranean fever; TNF receptor associated periodic syndrome; the cryopyrinopathies; mevalonate kinase deficiency; pediatric granulomatous arthritis; pyogenic arthritis, pyoderma gangrenosum and acne syndrome; Majeed syndrome; and deficiency of interleukin 1 receptor antagonist. The cryopyrinopathies discussed include neonatal-onset multisystem inflammatory disease (also known as chronic infantile neurologic, cutaneous and articular syndrome) Muckle-Wells syndrome, and familial cold autoinflammatory syndrome. CONCLUSIONS: Pediatricians must recognize the clinical features of the most prevalent autoinflammatory syndromes. Early referral to a pediatric rheumatologist may allow early diagnosis and institution of treatment, with improvement in the quality of life of these patients.

INTRODUCTION: The DiGeorge Syndrome was first described in 1968 as a primary immunodeficiency resulting from the abnormal development of the third and fourth pharyngeal pouches during embryonic life. It is characterized by hypocalcemia due to hypoparathyroidism, heart defects, and thymic hypoplasia or aplasia. Its incidence is 1:3000 live births and, despite its high frequency, little is known about its natural history and progression. ←This is probably due to diagnostic difficulties and the great variety of names used to describe it, such as velocardiofacial, Shprintzen, DiGeorge, and CATCH 22 Syndromes, as well as conotruncal facial anomaly. All represent the same genetic condition, chromosome 22q11.2 deletion, which might have several clinical expressions. OBJECTIVES: To describe clinical and laboratorial data and phenotypic characteristics of patients with DiGeorge Syndrome. METHODS: Patients underwent standard clinical and epidemiological protocol and tests to detect heart diseases, facial abnormalities, dimorphisms, neurological or behavioral disorders, recurrent infections and other comorbidities. RESULTS: Of 14 patients (8m - 18y11m), only one did not have 22q11.2 deletion detected. The main findings were: conotruncal malformation (n = 12), facial abnormalities (n = 11), hypocalcemia (n = 5) and low lymphocyte count (n=2). CONCLUSION: The authors pointed out the necessity of DGS suspicion in all patient presenting with heart defects, facial abnormalities (associated or not with hypocalcemia), and immunological disorders because although frequency of DGS is high, few patients with a confirmed diagnosis are followed up.

INTRODUÇÃO: Sintomas musculoesqueléticos podem representar a primeira manifestação de imunodeficiências humorais primárias. A freqüência de deficiência seletiva de IgA em pacientes com artrite idiopática juvenil (AIJ símile) e lúpus eritematoso sistêmico juvenil (LESJ) é de 2% a 4% e de 1% a 4%, respectivamente. OBJETIVO: Descrever pacientes que apresentaram artrite como primeiro sinal de uma imunodeficiência humoral primária e determinar a prevalência de deficiência seletiva de IgA em pacientes com diagnóstico de AIJ e LESJ. PACIENTES E MÉTODOS: Entre janeiro de 1983 e dezembro de 2006, 4.876 pacientes foram acompanhados na Unidade de Reumatologia Pediátrica. Uma avaliação retrospectiva foi realizada em pacientes que apresentaram artrite como primeira manifestação de imunodeficiência. As imunodeficiências humorais foram classificadas em: deficiência seletiva de IgA, hipogamaglobulinemia e deficiência de subclasses de IgG. RESULTADOS: Onze (0,2%) pacientes apresentaram imunodeficiências humorais: deficiência seletiva de IgA ocorreu em oito, imunodeficiência comum variável em dois e deficiência de subclasses de IgG em um. Cinco dos 11 pacientes apresentaram artrite aguda e seis apresentaram artrite crônica não-erosiva (AIJ símile). Dosagem de imunoglobulinas foi realizada em 70 dos 253 pacientes com AIJ e deficiência seletiva de IgA (IgA sérica < 7 mg/dL) foi detectada em 6 (8,5%) - AIJ símile. Dos 45 pacientes com LESJ, com dosagem de IgA realizada, 3 (6,6%) apresentaram deficiência seletiva de IgA. CONCLUSÃO: O presente estudo descreveu baixa prevalência de imunodeficiências humorais primárias em pacientes com doenças reumatológicas. Entretanto, a associação entre doenças auto-imunes e imunodeficiências sugere semelhanças em sua etiopatogenia e deve incentivar estudos prospectivos para investigação desta hipótese.INTRODUCTION: Rheumatologic findings may be the first manifestation of primary humoral immunodeficiencies. The frequency of selective IgA deficiency in patients with juvenile idiopathic arthritis (JIA like) and juvenile systemic lupus erithematosus (JSLE) is 2% to 4% and 1% to 4%, respectively. OBJECTIVE: To describe patients with primary humoral immunodeficiencies associated with arthritis and to determine the prevalence of selective IgA deficiency within JIA and JSLE patients. PATIENTS AND METHODS: From January 1983 to December 2006, 4.876 patients were followed at the Pediatric Rheumatology Unit. A retrospective evaluation was performed in patients that presented arthritis as the first clinical manifestation of immunodeficiency. The humoral immunodeficiencies were classified into selective IgA deficiency, hypogammaglobulinemia and IgG subclass deficiency. RESULTS: Eleven patients (0.2%) had primary immunodeficiency: selective IgA deficiency occurred in 8, common variable immunodeficiency in two, and IgG subclass deficiency in one. Five of the 11 patients had an acute arthritis and six patients a chronic nonerosive arthritis (JIA-like). From the 253 JIA patients evaluated, 70 had IgA level evaluation done and 6 (8.5%) presented complete IgA deficiency (serum IgA < 7 mg/dl) (JIA-like). From the 45 JSLE patients with IgA levels evaluated, 3 (6.6%) had selective IgA deficiency diagnosis. CONCLUSION: The present study showed a low prevalence of humoral immunodeficiency in patients with rheumatic diseases. However, this association suggests that similar defects in immune response could be related to both diseases and that prospective studies are needed to elucidate this hypothesis.

Placental transfer of maternal IgG antibodies to the fetus is an important mechanism that provides protection to the infant while his/her humoral response is inefficient. IgG is the only antibody class that significantly crosses the human placenta. This crossing is mediated by FcRn expressed on syncytiotrophoblast cells. There is evidence that IgG transfer depends on the following: (i) maternal levels of total IgG and specific antibodies, (ii) gestational age, (iii) placental integrity, (iv) IgG subclass, and (v) nature of antigen, being more intense for thymus-dependent ones. These features represent the basis for maternal immunization strategies aimed at protecting newborns against neonatal and infantile infectious diseases. In some situations, such as mothers with primary immunodeficiencies, exogenous IgG acquired by intravenous immunoglobulin therapy crosses the placenta in similar patterns to endogenous immunoglobulins and may also protect the offspring from infections in early life. Inversely, harmful autoantibodies may cross the placenta and cause transitory autoimmune disease in the neonate.

OBJECTIVE: To investigate the transmission of anti-Staphylococcus aureus (Sa) IgG, IgG1 and IgG2 via placental transfer and the transfer of IgA via the colostrum according to maternal Sa carrier status at delivery. METHODS: We evaluated anti-Sa IgG, IgG1 and IgG2 in maternal and cord sera and IgA in colostrum from a case (n=49, Sa+) and a control group (n=98, Sa-). RESULTS: Of the 250 parturients analyzed for this study, 49 were nasally colonized with S. aureus (prevalence of 19.6%). Ninety-eight non-colonized subjects were selected for the control group. The anti-Sa IgG, IgG1 and IgG2 levels and the IgG avidity indexes in the maternal and cord sera did not differ between the groups, with a low transfer ratio of anti-Sa IgG to the newborns in both groups. The anti-Sa IgG2 titers were significantly higher than the IgG1 titers in the maternal and cord sera. Inversely, the transfer ratios were higher for anti-Sa IgG1 compared with IgG2; however, no differences between the groups were detected. The Sa-specific IgA levels and avidity indexes in the colostrum were equivalent between groups. CONCLUSIONS: Maternal Sa nasal colonization at delivery is not associated with higher antibody levels in the mother or newborns. The high titers of anti-Sa IgG2 found in the cord serum indicate a greater reactivity with non-protein antigens, which may further contribute to the susceptibility to staphylococcal infections at birth. The presence of IgA in the colostrum with avidity to S. aureus reinforces the importance of breastfeeding shortly after birth.