Primary immunodeficiency diseases in different age groups: a report on 1,008 cases from a single Brazilian reference center.

Primary immunodeficiencies (PIDs) represent a large group of diseases that affect all age groups. Although PIDs have been recognized as rare diseases, there is epidemiological evidence suggesting that their real prevalence has been underestimated. We performed an evaluation of a series of 1,008 infants, children, adolescents and adults with well-defined PIDs from a single Brazilian center, regarding age at diagnosis, gender and PID category according to the International Union of Immunological Societies classification. Antibody deficiencies were the most common category in the whole series (61 %) for all age groups, with the exception of <2-year-old patients (only 15 %). In the >30-year-old group, antibody deficiencies comprised 84 % of the diagnoses, mostly consisting of common variable immunodeficiency, IgA deficiency and IgM deficiency. Combined immunodeficiencies represented the most frequent category in <2-years-old patients. Most congenital defects of phagocytes were identified in patients <5 -years of age, as were the diseases of immune dysregulation, with the exception of APECED. DiGeorge syndrome and ataxia-telangiectasia were the most frequent entities in the category of well-defined syndromes, which were mostly identified in patients <10-years of age. Males represented three-quarters and two-thirds of <2 -years-old and 2-5-years -old patients, respectively, whereas females predominated among the >30-year-old patients. Our data indicated that some PIDs were only detected at early ages, likely because affected patients do not survive long. In addition, our data pointed out that different strategies should be used to search for PIDs in infants and young children as compared to older patients.

Inversion of the Vδ1 to Vδ2 γδ T cell ratio in CVID is not restored by IVIg and is associated with immune activation and exhaustion.

Common variable immunodeficiency (CVID) is defined by low levels of IgG and IgA, but perturbations in T cells are also commonly found. However, there is limited information on γδ T cells in CVID patients. Newly diagnosed CVID patients (n = 15) were enrolled before and after intravenous IgG (IVIg) replacement therapy. Cryopreserved peripheral blood mononuclear cells were then used to study γδ T cells and CVID patients were compared to healthy controls (n = 22). The frequency and absolute count of Vδ1 γδ T cells was found to be increased in CVID (median 0.60% vs 2.64%, P <0.01 and 7.5 vs 39, P <0.01 respectively), while they were decreased for Vδ2 γδ T cells (median, 2.36% vs 0.74%, P <0.01 and 37.8 vs 13.9, P <0.01 respectively) resulting in an inversion of the Vδ1 to Vδ2 ratio (0.24 vs 1.4, P <0.001). Markers of immune activation were elevated on all subsets of γδ T cells, and HLA-DR expression was associated with an expansion of Vδ1 γδ T cells (r = 0.73, P = 0.003). Elevated PD-1 expression was found only on Vδ2 γδ T cells (median 1.15% vs 3.08%, P <0.001) and was associated with the decrease of Vδ2 γδ T cells (r = -0.67, P = 0.007). IVIg had no effect on the frequency of Vδ1 and Vδ2 γδ T cells or HLA-DR expression, but alleviated CD38 expression on Vδ1 γδ T cells (median MFI 965 vs 736, P <0.05). These findings suggest that immunological perturbations of γδ T cells are a general feature associated with CVID and are only partially reversed by IVIg therapy.

Vacina rotavírus: segurança e alergia alimentar ­ Posicionamento das Sociedades Brasileiras de Alergia e Imunologia (ASBAI), Imunizações (SBIm) e Pediatria (SBP) / Rotavirus vaccine: safety and food allergy ­ Position paper of the Brazilian Societies of Allergy and Immunology (ASBAI), Immunizations (SBIm), and Pediatrics (SBP)

O rotavírus continua sendo o principal agente causador de diarreia na criança, a despeito da ampla utilização de vacinas nos programas públicos de vacinação em todo o mundo. No Brasil, a vacina monovalente foi introduzida no Programa Nacional de Imunizações (PNI) em 2006, e a segurança da vacina está bem documentada em diferentes estudos pré e pós-licenciamento. Embora não haja nenhuma associação entre o uso da vacina rotavírus e o desenvolvimento da alergia às proteínas do leite de vaca (APLV), existe o receio, por parte de alguns pediatras e familiares, da vacina estar relacionada ao surgimento ou desencadeamento desta reação de hipersensibilidade. Este artigo faz uma revisão dos dados de segurança da vacina e aborda aspectos imunológicos das reações de hipersensibilidade, demonstrando não haver nexo causal entre a vacina e a APLV, reforçando o posicionamento e recomendações de organismos nacionais, internacionais e das sociedades científicas.

Despite the widespread use of vaccines in public immunization programs worldwide, rotavirus remains the primary cause of diarrhea in children. In Brazil, the monovalent vaccine was introduced in the National Immunization Program (Programa Nacional de Imunizações - PNI) in 2006, and its safety is well documented in different studies carried out both before and after licensing. Even though there is no association between the use of rotavirus vaccine and the development of cow's milk protein allergy (CMPA), some pediatricians and family members fear that the vaccine may be somehow related to the emergence or outbreak of this hypersensitivity reaction. This article reviews safety data available for this vaccine and addresses the immunological aspects of hypersensitivity reactions. The findings demonstrate that there is no causal link between the rotavirus vaccine and CMPA, reinforcing the position and recommendations of national and international agencies as well as of scientific societies.

Avaliação da resposta clínica dos pacientes com imunodeficiência comum variável submetidos à vacinação com antígenos proteicos e polissacarídicos / Clinical evaluation of patients with common variable immunodeficiency before and after immunization with polysaccharide and protein antigens

OBJETIVO: Avaliar a resposta clínica a imunização com antígenos proteicos e polissacarídicos após administração de vacinas de antígenos específicos (Pneumococo e Influenza H2N3 e H1N1) em pacientes com imunodeficiência comum variável (ICV) acompanhados no ambulatório de Imunodeficiências Primáriasdo Serviço de Imunologia Clínica e Alergia, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). MÉTODOS: Os pacientes foram diagnosticados segundo critérios da OMS, PAGID e ESID. Os pacientes foram vacinados contra Influenza H2N3, Influenza H1N1 e Pneumococo. A avaliação clínica foi realizada a partir de um escore clínico no qual os parâmetros considerados foram: pneumonias, sinusites, otite média aguda, infecções de vias aéreas superiores virais (IVAS), amigdalite, diarreia, bronquiectasias, hospitalizações, uso de antibiótico terapêutico, uso de antibiótico profilático, sepse e meningite. Avaliação do escore clínico foi realizada durante o ano que precedeu a vacinação e um ano após a administração das vacinas. RESULTADOS: Participaram do estudo 45 pacientes (51% mulheres), com idade entre 20 a 78 anos (média 36,3 anos). Observamos mediana de 7 anos de retardo no diagnóstico dos pacientes com ICV. IVAS, pneumonias e sinusites foram as manifestações infecciosas mais frequentes em mulheres (80%, 78% e 55% respectivamente). IVAS, sinusites e pneumonias foram os achados mais frequentes em homens (78%, 65% e 35% respectivamente). Houve redução significativa do escore clínico em relação ao número de sinusites e IVAS após a administração das vacinas (p < 0,001).CONCLUSÕES: Observamos redução do número de infecções, especialmente sinusites e IVAS no ano posterior à vacinação. Esta observação reforça o benefício da vacinação e sugere modificação na orientação quanto às indicações de vacinas nos pacientes com ICV.

Objective: To evaluate clinical response to immunization with polysaccharide and protein antigens following administration of specific antigen vaccines (Pneumococcus and Influenza H2N3 and H1N1) in patients with common variable immunodeficiency (CVID) treated at the Primary Immunodeficiency Outpatient Clinic of the Division of Clinical Immunology and Allergy at the Clinical Hospital of the School of Medicine of University of São Paulo (HC-FMUSP). Methods: Patients were diagnosed according to WHO, PAGID, and ESID criteria. Patients were vaccinated against Influenza H2N3, Influenza H1N1, and Pneumococcus. Clinical evaluation was performed using clinical scores for the following parameters: pneumonia, sinusitis, acute otitis media, viral upper respiratory tract infections (URI), tonsillitis, diarrhea, bronchiectasis, hospitalizations, antibiotic therapy, antibiotic prophylaxis, sepsis, and meningitis. Evaluation focused on one year prior to immunization and one year after the administration of vaccines. Results: A total of 45 patients (51% women), aged 20 to 78 years (mean 36.3 years), were evaluated. A median delay of 7 years was observed in the diagnosis of patients with CVID. URI, pneumonia, and sinusitis were the most frequent infectious conditions found in women (80%, 78%, and 55%, respectively); URI, sinusitis, and pneumonia were the most frequent findings in men (78%, 65%, and 35%, respectively). There was a significant reduction in the clinical scores assigned to the number of sinusitis and URI episodes following administration of the vaccines (p < 0.001). Conclusions: A reduction was observed in the number of infections, particularly sinusitis and URI, in the year following immunization. This finding reinforces the benefit of vaccination and suggests modifications to current recommendations for vaccines in patients with CVID.