RESUMO
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 7.91g/L (range, 4.59-12.20). All patients had antibody levels above 0.35µg/mL to the six serotypes on all four measurements. However, only 28.6% of patients had pneumococcal antibodies for the six analysed serotypes above 1.3µg/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.
Assuntos
Anticorpos Antibacterianos/sangue , Imunoglobulinas Intravenosas/uso terapêutico , Síndromes de Imunodeficiência/imunologia , Pneumonia Pneumocócica/imunologia , Streptococcus pneumoniae/imunologia , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Imunoglobulina G/sangue , Síndromes de Imunodeficiência/terapia , Masculino , Pneumonia Pneumocócica/terapia , Estudos Prospectivos , Adulto JovemRESUMO
Tuberculosis (TB) infection was evaluated in Brazilian immunocompetent children and adolescents exposed and unexposed (control group) to adults with active pulmonary TB. Both groups were analysed by clinical and radiological assessment, TST, QFT-IT and T-SPOT.TB. The three tests were repeated after 8 weeks in the TB-exposed group if results were initially negative. Individuals with latent tuberculosis infection (LTBI) were treated and tests were repeated after treatment. Fifty-nine TB-exposed and 42 controls were evaluated. Rate of infection was 69·5% and 9·5% for the exposed and control groups, respectively. The exposed group infection rate was 61% assessed by TST, 57·6% by T-SPOT.TB, and 59·3%, by QFT-IT. No active TB was diagnosed. Agreement between the three tests was 83·1% and 92·8% in the exposed and control groups, respectively. In the exposed group, T-SPOT.TB added four TB diagnoses [16%, 95% confidence interval (CI) 1·6-30·4] and QFT-IT added three TB diagnoses (12%, 95% CI 0-24·7) in 25 individuals with negative tuberculin skin test (TST). Risk factors associated to TB infection were contact with an adult with active TB [0-60 days: odds ratio (OR) 6·9; >60 days: OR 27·0] and sleeping in the same room as an adult with active TB (OR 5·2). In Brazilian immunocompetent children and adolescents, TST had a similar performance to interferon-gamma release assays and detected a high rate of LTBI.
Assuntos
Testes de Liberação de Interferon-gama/métodos , Mycobacterium tuberculosis/isolamento & purificação , Teste Tuberculínico/métodos , Tuberculose/epidemiologia , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Prevalência , Fatores de Risco , Tuberculose/microbiologiaRESUMO
Children born to female kidney recipients are exposed to immunosuppressive drugs during gestation. Little is known about their immune system at birth or in the long term. Twenty-eight children born to female kidney recipients and 40 full-term children born to healthy mothers were evaluated. T, B, NK, NKT, γδT cells were assessed by flow cytometry and functional evaluation of T and dendritic cells after in vitro activation was performed at birth and at 8 months of age. At birth, infants born to female kidney recipients showed lower numbers of CD4+ T, NKT and intense reduction of B cells (median cells/mm(3) , transplant: 153.7 X control: 512.4; p < 0.001). There was also a reduced percentage of activated CD8+ T and of CD4+ regulatory T cells. Activated memory and exhausted memory B cells showed higher percentages among children exposed to immunosuppressors when compared to control group. At 8 months, most immune alterations were no longer observed, but four children still had low numbers of some lymphocyte subsets at this age. Children born to female kidney recipients had 4.351 (95% CI: 1.026-15.225; p = 0.046) higher risk of hospital admission in the first months of life-some, with severe clinical manifestations-than those born to healthy women.
Assuntos
Hospitalização/estatística & dados numéricos , Imunofenotipagem , Infecções/epidemiologia , Transplante de Rim , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Transplantados , Imunidade Adaptativa/efeitos dos fármacos , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Idade Gestacional , Rejeição de Enxerto/prevenção & controle , Humanos , Imunidade Inata/efeitos dos fármacos , Imunossupressores/efeitos adversos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Lactente , Recém-Nascido , Gravidez , Fatores de Risco , Linfócitos T Reguladores/patologia , Adulto JovemRESUMO
BACKGROUND: PIDs are a heterogeneous group of genetic illnesses, and delay in their diagnosis is thought to be caused by a lack of awareness among physicians concerning PIDs. The latter is what we aimed to evaluate in Brazil. METHODS: Physicians working at general hospitals all over the country were asked to complete a 14-item questionnaire. One of the questions described 25 clinical situations that could be associated with PIDs and a score was created based on percentages of appropriate answers. RESULTS: A total of 4026 physicians participated in the study: 1628 paediatricians (40.4%), 1436 clinicians (35.7%), and 962 surgeons (23.9%). About 67% of the physicians had learned about PIDs in medical school or residency training, 84.6% evaluated patients who frequently took antibiotics, but only 40.3% of them participated in the immunological evaluation of these patients. Seventy-seven percent of the participating physicians were not familiar with the warning signs for PIDs. The mean score of correct answers for the 25 clinical situations was 48.08% (±16.06). Only 18.3% of the paediatricians, 7.4% of the clinicians, and 5.8% of the surgeons answered at least 2/3 of these situations appropriately. CONCLUSIONS: There is a lack of medical awareness concerning PIDs, even among paediatricians, who have been targeted with PID educational programmes in recent years in Brazil. An increase in awareness with regard to these disorders within the medical community is an important step towards improving recognition and treatment of PIDs.
Assuntos
Competência Clínica/estatística & dados numéricos , Síndromes de Imunodeficiência/epidemiologia , Médicos/estatística & dados numéricos , Brasil , Estudos Transversais , Cirurgia Geral , Hospitais Gerais , Humanos , Síndromes de Imunodeficiência/diagnóstico , Medicina Interna , Pediatria , Papel do Médico , Prática Profissional , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Severe combined immunodeficiency (SCID) is one of the most severe forms of primary immunodeficiency. The objectives of this study were to analyze the diagnosis, treatment, and prognosis of SCID in Brazil and to document the impact of BCG vaccine. METHODS: We actively searched for cases by contacting all Brazilian referral centers. RESULTS: We contacted 23 centers and 70 patients from 65 families. Patients were born between 1996 and 2011, and 49 (70%) were male. More than half (39) of the diagnoses were made after 2006. Mean age at diagnosis declined from 9.7 to 6.1 months (P = .058) before and after 2000, respectively, and mean delay in diagnosis decreased from 7.9 to 4.2 months (P = .009). Most patients (60/70) were vaccinated with BCG before the diagnosis, 39 of 60 (65%) had complications related to BCG vaccine, and the complication was disseminated in 29 of 39 (74.3%). Less than half of the patients (30, 42.9%) underwent hematopoietic stem cell transplantation (HSCT). Half of the patients died (35, 50%), and 23 of these patients had not undergone HSCT. Disseminated BCG was the cause of death, either alone or in association with other causes, in 9 of 31 cases (29%, no data for 4 cases). CONCLUSIONS: In Brazil, diagnosis of SCID has improved over the last decade, both in terms of the number of cases and age at diagnosis, although a much higher number of cases had been expected. Mortality is higher than in developed countries. Complications of BCG vaccine are an important warning sign for the presence of SCID and account for significant morbidity during disease progression.
Assuntos
Vacina BCG/efeitos adversos , Imunodeficiência Combinada Severa/terapia , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Imunodeficiência Combinada Severa/complicações , Imunodeficiência Combinada Severa/epidemiologiaRESUMO
BACKGROUND: Patients with common variable immunodeficiency (CVID) present with low antibody levels, impaired lymphocyte function, and chronic inflammation. Vitamin A and zinc are essential components of the immune system and can be redistributed in the body as a result of inflammation. OBJECTIVE: To compare levels of retinol, beta-carotene, and zinc in patients with CVID and healthy controls after evaluating a series of parameters for each participant. PATIENTS AND METHODS: We performed a cross-sectional study of CVID patients and healthy controls matched for age and gender. All participants underwent a nutritional and laboratory evaluation comprising a complete blood count and determination of levels of C-reactive protein (CRP), lipopolysaccharide (LPS), soluble CD14 (sCD14), retinol, beta-carotene, and serum and erythrocyte zinc. RESULTS: We included 17 patients (mean age, 28.54 years) and 17 controls. Mean (SD) retinol levels were lower in patients: 1.99 (0.67) micromol/L vs 2.72 (0.96) micromol/L. Median beta-carotene levels were similar in both groups (0.30 micromol/L). Median serum zinc levels were 50.0 microg/dL (50-100 microg/dL) in the patients and 100.0 microg/dL (50-150 microg/dL) in the controls. Mean levels of erythrocyte zinc were lower among patients: 37.32 (10.51) microgZn/gHb vs 44.91 (7.67) microgZn/gHb in the controls. Median CRP levels were significantly higher among patients: 4.99 (0.15-34.51) mg/L vs 0.55 (0.17-6.06) mg/L. No differences in translocation marker levels were observed between the groups. CONCLUSIONS: CVID patients had lower levels of retinol and zinc than controls. Since micronutrient deficiency could aggravate their disease and contribute to chronic inflammation, micronutrient status should always be assessed in patients with primary immunodeficiency.
Assuntos
Imunodeficiência de Variável Comum/diagnóstico , Estado Nutricional/imunologia , Vitamina A/sangue , Zinco/metabolismo , Adolescente , Adulto , Proteína C-Reativa/metabolismo , Imunodeficiência de Variável Comum/metabolismo , Eritrócitos/metabolismo , Feminino , Humanos , Receptores de Lipopolissacarídeos/sangue , Masculino , Adulto Jovem , beta Caroteno/sangueRESUMO
IPEX is a rare X-linked syndrome, with immune dysfunction, polyendocrinopathy and enteropathy. We describe an infant who died at the age of 11 months after developing eczema, severe diarrhoea, diabetes, hypothyroidism, thrombocytopenia and four episodes of septicaemia. Immunophenotyping of peripheral blood at 8 months revealed normal CD3+ T, CD4+ T and CD8+ T cell numbers, with low NK and B cells. CD4+ and CD8+ T lymphocytes showed remarkably low numbers and percentages of naïve cells and high numbers of memory CD4 and CD8 cells. At autopsy, an intense depletion of immune cells in thymus, spleen and lymph nodes was observed. No Hassall's corpuscles were found in thymus. Lymphocytic pancreatitis and intense villous atrophy with mucosal lymphocytic infiltration in small bowel were also seen. FOXP3 gene studies revealed a: C-->G substitution 3 bp upstream of exon 10, which prevents splicing between exons 9 and 10, likely resulting in a functionally altered or deficient protein. Florid clinical findings are usually observed in association of forkhead DNA-binding domain mutations. The intense depletion of naïve T cells we report suggest that depletion of immune cells might take place due to uncontrolled activation due to the absence of regulatory T cells.
Assuntos
Fatores de Transcrição Forkhead/genética , Linfócitos T/imunologia , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/genética , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/imunologia , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Memória Imunológica , Recém-Nascido , Masculino , MutaçãoRESUMO
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.
Assuntos
ELISPOT/estatística & dados numéricos , Testes de Liberação de Interferon-gama/estatística & dados numéricos , Teste Tuberculínico/estatística & dados numéricos , Tuberculose/diagnóstico , Adolescente , Brasil , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Hospedeiro Imunocomprometido , Lactente , Masculino , Adulto JovemRESUMO
Tetanus and diphtheria vaccines are of special concern in adolescents because boosters are necessary for adequate maintenance of protection and are often omitted. We assessed serum levels of tetanus and diphtheria antibodies in adolescents and their association with vaccination status. From May to October 2001, we evaluated the vaccination records of 208 adolescents aged 10 to 20 years in São Paulo, Brazil. Antibodies to tetanus and diphtheria were detected using double-antigen ELISA and vaccination records were analyzed according to the guidelines of the Brazilian National Immunization Program. All adolescents had received complete primary vaccinations against tetanus and diphtheria, but 23.1% of them had not received a booster dose in the last 10 years. All adolescents were immune to tetanus and 88.9% were fully protected (antibodies (3)0.1 IU/mL). One individual (0.5%) was non-immune to diphtheria and 86% were fully protected against the disease. Adolescents with up-to-date vaccination records had higher antibody levels than those with not up-to-date records for tetanus (0.763 vs 0.239 IU/mL, t-test: P < 0.0001) and diphtheria (0.366 vs 0.233 IU/mL, t-test: P = 0.014). Full immunity against tetanus (antibodies (3)0.1 IU/mL) was higher among individuals with up-to-date vaccination (93.1%) when compared to those with not up-to-date records (75%, Fisher's exact test: P = 0.001). All adolescents had received basic immunization in childhood and were protected against tetanus and diphtheria. However, these data indicate that more emphasis should be placed on the tetanus-diphtheria booster in order to avoid a decay in antibody levels.
Assuntos
Anticorpos Antibacterianos/sangue , Vacina contra Difteria e Tétano/imunologia , Difteria/prevenção & controle , Tétano/prevenção & controle , Adolescente , Adulto , Anticorpos Antibacterianos/imunologia , Brasil , Criança , Difteria/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Tétano/imunologiaRESUMO
Epidemiological data regarding tetanus and diphtheria immunity in elderly people in Brazil are scarce. During the First National Immunization Campaign for the Elderly in Brazil in April 1999, 98 individuals (median age: 84 years) received one tetanus-dyphtheria (Td) vaccine dose (Butantan Institute, lot number 9808079/G). Inclusion criteria were elderly individuals without a history of severe immunosuppressive disease, acute infectious disease or use of immunomodulators. Blood samples were collected immediately before the vaccine and 30 days later. Serum was separated and stored at -20 degrees C until analysis. Tetanus and diphtheria antibodies were measured by the double-antigen ELISA test. Tetanus and diphtheria antibody concentrations lower than 0.01 IU/mL were considered to indicate the absence of protection, between 0.01 and 0.09 IU/mL were considered to indicate basic immunity, and values of 0.1 IU/mL or higher were considered to indicate full protection. Before vaccination, 18% of the individuals were susceptible to diphtheria and 94% were susceptible to tetanus. After one Td dose, 78% became fully immune to diphtheria, 13% attained basic immunity, and 9% were still susceptible to the disease. In contrast, 79% remained susceptible to tetanus, 4% had basic immunity and 17% were fully immune. Although one Td dose increases immunity to diphtheria in many elderly people who live in Brazil, a complete vaccination series appears to be necessary for the prevention of tetanus.
Assuntos
Anticorpos Antibacterianos/sangue , Vacina contra Difteria e Tétano/imunologia , Difteria/prevenção & controle , Tétano/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/imunologia , Brasil , Difteria/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Tétano/imunologiaRESUMO
The immunogenicity and tolerability of hepatitis A virus vaccine was evaluated in a group of 32 children with human immunodeficiency virus (HIV) infection and 27 children with seroreversion. After 2 doses of vaccine, 100% of children experienced seroconversion with good toleration of the vaccine. There were no differences in variation of virus load between immunized HIV-positive children and a group of 31 nonimmunized HIV-positive children with similar characteristics.
Assuntos
Infecções por HIV/imunologia , Anticorpos Anti-Hepatite A/biossíntese , Vacinas contra Hepatite A/imunologia , Tolerância Imunológica , Terapia Antirretroviral de Alta Atividade , Criança , Infecções por HIV/tratamento farmacológico , Anticorpos Anti-Hepatite A/sangue , Vacinas contra Hepatite A/administração & dosagem , HumanosRESUMO
Human herpesvirus-8 (HHV-8) appears to be transmitted mainly by sexual contact. However, several studies suggest that in developing countries the infection may be acquired early in life by routes other than sexual transmission. The present study estimated the seroprevalence of HHV-8 in Brazilian children born to HIV-1-infected mothers. The serum samples were collected in a cross-sectional cohort study from 99 children born to HIV-infected mothers (median age 3.27 years; range 1.5-13.8 years) attending the outpatient clinic of the Federal University of Sao Paulo. IgG antibodies to HHV-8 latency-associated nuclear antigen and lytic phase antigens were detected by immunofluorescence assays. The samples tested were collected from children aged 12 months or older to exclude the possibility of cross-placental antibody transport. The total prevalence of anti-lytic antibodies in this population (5/99; 5%) reveals that HHV-8 infection can occur during childhood. Children aged 1.5 to 2 years had a seroprevalence of 2% (1/50) and children aged 3.25 to 13.8 years had a seroprevalence of 8% (4/49). This difference was not statistically significant, probably because of the small size of the sample, but it suggests that HHV-8 infection occurs more commonly late in infancy. Further prospective studies are necessary to evaluate the timing and risk factors for primary HHV-8 infection in the pediatric population.
Assuntos
Infecções por HIV/complicações , HIV-1/imunologia , Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/imunologia , Complicações Infecciosas na Gravidez/virologia , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Métodos Epidemiológicos , Feminino , Técnica Direta de Fluorescência para Anticorpo , Anticorpos Anti-HIV/sangue , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/transmissão , Infecções por Herpesviridae/virologia , Humanos , Imunoglobulina G/sangue , Lactente , Transmissão Vertical de Doenças Infecciosas , Masculino , GravidezRESUMO
An increased incidence of pertussis has been observed recently in adults, and healthcare workers (HCWs) are considered a risk group for transmission to infants. Prevalence of recent pertussis infection was assessed in HCWs from a paediatric department of a tertiary care hospital in Brazil. Serum pertussis toxin IgG antibodies were measured by enzyme-linked immunosorbent assay. Of 388 HCWs included in the analysis, 6.4% had serology suggestive of recent infection. Medical residents [odds ratio (OR): 4.15; 95% confidence interval (CI): 1.42-12.14; P = 0.009] and those working >40 h a week (OR: 3.29; 95% CI: 1.17-9.26; P = 0.024) had increased risk of pertussis infection.
Assuntos
Infecção Hospitalar/epidemiologia , Transmissão de Doença Infecciosa/prevenção & controle , Transmissão de Doença Infecciosa/estatística & dados numéricos , Pessoal de Saúde/estatística & dados numéricos , Hospitais Pediátricos/estatística & dados numéricos , Centros de Atenção Terciária/estatística & dados numéricos , Coqueluche/epidemiologia , Adulto , Idoso , Bordetella pertussis , Brasil/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto JovemRESUMO
The acquisition of maternal immunoglobulin G (IgG) is fundamental to the immune defence of the neonate. The receptor responsible for IgG transfer across the human placenta has also been implicated in the maintenance of IgG levels in the circulation. beta2-microglobulin is part of the Fc receptor (FcR) that has recently been purified from the human placenta. In HIV infection, increasing serum levels of total IgG and beta2-microglobulin are observed as the disease progresses. Herein, we have investigated the correlation between beta2-microglobulin and total serum IgG levels in HIV-seropositive mothers and their term neonates (HIV group, n = 37), as well as in HIV-seronegative mothers and their term neonates (control group, n = 50). Serum maternal beta2-microglobulin was directly correlated with total serum IgG levels in HIV-infected mothers (r = 0.58; P = 0.0002), but not in healthy HIV-seronegative mothers (r = -0.20; P = 0.16). Maternal serum beta2-microglobulin was also inversely correlated with placental antibody transfer of total IgG in mother-newborn pairs from the HIV group (r = 0.38; P = 0.02), but not from the control group (r = 0.15. P = 0.31). These results seem to indicate that, in HIV infection, elevated serum beta2-microglobulin levels could be involved in maintenance of abnormally high total serum IgG concentrations; by interfering with the binding of IgG to Fc receptors at the maternal-fetal interface, they might also reduce IgG transfer. By contrast, in normal non-HIV infected individuals, serum beta2-microglobulin levels do not appear implicated in regulation of these two phenomena.
Assuntos
Infecções por HIV/imunologia , Imunidade Materno-Adquirida/imunologia , Imunoglobulina G/imunologia , Placenta/imunologia , Microglobulina beta-2/imunologia , Adulto , Feminino , Humanos , Imunoglobulina G/sangue , Recém-NascidoRESUMO
Although frequently reported in the literature, a staff varicella policy is not standard in many hospitals even in developed countries. In the present study, we assessed varicella zoster immunity in staff from two neonatal units from hospitals in São Paulo, Brazil. Ninety-seven percent of all staff working in both units agreed to participate. A simple and cost-effective varicella policy was subsequently set up, based on costs and data from serology and a history of previous varicella infection. Our results confirm that a varicella vaccination programme can be implemented in a healthcare facility, even in developing countries.
Assuntos
Anticorpos/imunologia , Pessoal de Saúde , Herpesvirus Humano 3/imunologia , Vacinas contra Herpesvirus/imunologia , Adulto , Brasil , Feminino , Política de Saúde/economia , Departamentos Hospitalares , Humanos , Masculino , Pessoa de Meia-Idade , NeonatologiaRESUMO
AIM: To determine the influence of placental malaria, maternal HIV infection, and maternal hypergammaglobulinaemia on transplacental IgG antibody transfer. METHODS: One hundred and eighty materno-neonatal pairs from a Malawian population were assessed. Cord and maternal serum samples were tested for total serum IgG antibody titres using nephelometry, and for specific IgG antibody titres to Streptococcus pneumoniae, measles, and tetanus toxoid antibodies using an enzyme linked immunosorbent assay (ELISA). RESULTS: Multiple regression analyses showed that placental malaria was associated with a decrease in placental IgG antibody transfer to S pneumoniae and measles to 82% and 81%, respectively. Maternal HIV infection was associated with a reduction in IgG antibody transfer to S pneumoniae to 79%; raised maternal total serum IgG titres were correlated with S pneumoniae and measles IgG antibody transfer reduction to 86% and 87%, respectively. No effect was seen with tetanus toxoid antibody transfer. CONCLUSION: The combined influence of placental malaria, maternal HIV infection, and maternal hypergammaglobulinaemia seems to be linked to the low transplacental antibody transfer observed in the Malawian population.
Assuntos
Infecções por HIV/imunologia , Hipergamaglobulinemia/imunologia , Imunidade Materno-Adquirida , Malária Falciparum/imunologia , Placenta/imunologia , Adulto , Anticorpos Antibacterianos/metabolismo , Anticorpos Antivirais/metabolismo , Feminino , Humanos , Imunoglobulina G/metabolismo , Recém-Nascido , Malaui , Troca Materno-Fetal , Sarampo/imunologia , Placenta/parasitologia , Placenta/virologia , Gravidez , Streptococcus pneumoniae/imunologiaRESUMO
A flow cytometry-adapted fluorescent antibody to membrane antigen (FAMA) assay to detect IgG antibodies against varicella-zoster virus (VZV) was developed and tested in 62 serum samples, showing 90.32% accuracy obtained from a receiver operating characteristic (ROC) curve with a 0.9125 (95% confidence interval [CI], 0.829 to 1.00) area below the curve compared to the result with standard FAMA.
Assuntos
Anticorpos Antivirais/sangue , Citometria de Fluxo , Imunofluorescência , Herpesvirus Humano 3/imunologia , Imunidade , Antígenos de Superfície , Humanos , Imunoglobulina G/sangue , Curva ROC , Sensibilidade e EspecificidadeRESUMO
The immune consequences of in utero HIV exposure to uninfected children whose mothers were submitted to highly active antiretroviral therapy (HAART) during gestation are not well defined. We evaluated 45 HIV-exposed uninfected (ENI) neonates and 45 healthy unexposed control (CT) neonates. All HIV-infected mothers received HAART during pregnancy, and the viral load at delivery was <50 copies/mL for 56.8%. Twenty-three ENI neonates were further evaluated after 12 months and compared to 23 unexposed healthy age-matched infants. Immunophenotyping was performed by flow cytometry in cord and peripheral blood. Cord blood lymphocyte numbers did not differ between groups. However, ENI neonates had a lower percentage of naive T cells than CT neonates (CD4+, 76.6 vs 83.1%, P < 0.001; CD8+, 70.9 vs 79.6%, P = 0.003) and higher percentages of central memory T cells than CT neonates (CD4+, 13.9 vs 8.7%, P < 0.001; CD8+, 8.6 vs 4.8%, P = 0.001). CD38 mean fluorescence intensity of T cells was higher in ENI neonates (CD4+, 62.2 vs 52.1, P = 0.007; CD8+, 47.7 vs 35.3, P < 0.001). At 12 months, ENI infants still had higher mean fluorescence intensity of CD38 on T cells (CD4+, 34.2 vs 23.3, P < 0.001; CD8+, 26.8 vs 19.4, P = 0.035). Despite effective maternal virologic control at delivery, HIV-exposed uninfected children were born with lower levels of naive T cells. Immune activation was present at birth and remained until at least 12 months of age, suggesting that in utero exposure to HIV causes subtle immune abnormalities.
Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/imunologia , Memória Imunológica/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Contagem de Células Sanguíneas , Estudos de Casos e Controles , Feminino , Sangue Fetal , Citometria de Fluxo , Infecções por HIV/prevenção & controle , Humanos , Memória Imunológica/efeitos dos fármacos , Imunofenotipagem , Lactente , Ativação Linfocitária/imunologia , Masculino , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Efeitos Tardios da Exposição Pré-Natal/imunologia , Carga Viral , Adulto JovemRESUMO
The introduction of routine vaccination against tetanus and diphtheria in Brazil has decreased the incidence and changed the epidemiology of both diseases. We then investigated the prevalence of Corynebacterium diphtheriae carrier status and diphtheria and tetanus immunity in São Paulo, Brazil. From November 2001 to March 2003, 374 individuals were tested for the presence of C. diphtheriae in the naso-oropharynx and of serum diphtheria and tetanus antibodies. Participants were all healthy individuals without acute or chronic pathologies and they were stratified by age as follows: 0-12 months and 1-4, 5-9, 10-14, 15-24, 25-39, 40-59, and > or =60 years. Antibodies were assessed using a double-antigen ELISA. C. diphtheriae species were identified by biochemical analysis and toxigenicity was assessed by the Elek test. For diphtheria, full protection (antibodies > or =0.1 IU/mL) was present in 84% of the individuals, 15% had basic protection (antibodies > or =0.01 and <0.1 IU/mL) and 1% were susceptible (antibodies <0.01 IU/mL). Full tetanus protection (antibodies > or =0.1 IU/mL) was present in 79% of the participants, 18% had basic protection (antibodies > or =0.01 and <0.1 IU/mL) and 3% were susceptible (antibodies <0.01 IU/mL). The geometric mean of diphtheria and tetanus antibodies reached the highest values at 5-9 years and decreased until the 40-59-year age range, increasing again in individuals over 60 years. Three participants (0.8%) were carriers of C. diphtheriae, all non-toxigenic strains. The present results demonstrate the clear need of periodic booster for tetanus and diphtheria vaccine in adolescents and adults after primary immunization in childhood.