Doença de Chagas crônica: do xenodiagnóstico e hemocultura à reação em cadeia da polimerase

Although there has been an improvement in the diagnosis of chronic Chagas' disease, the low sensitivity of indirect parasitological tests is a drawback to its application in diagnosis and post-therapeutic control. Polymerase chain reaction (PCR) has limited use in routine diagnosis due to the need of specific laboratory facilities, common DNA cross-contamination, and high costs. At the same time, the high variability of PCR results found in different regions of Brazil raises some questions concerning its applicability for diagnosis. PCR's high specificity is indicative that it can be used as a confirmation method in inconclusive serology diagnosis as well as an auxiliary method in pos-therapeutic control of chronic Chagas' disease when comparing to serology and parasitological techniques. It is discussed here the applicability of molecular and indirect parasitological methods in the diagnosis and post-therapeutic control of chronic Chagas' disease based on the literature published from 1954 to 2001.Embora tenham ocorrido aprimoramentos no diagnóstico parasitológico da doença de Chagas crônica, a baixa sensibilidade dos exames indiretos é uma limitação para sua aplicação ao diagnóstico e controle pós-terapêutico. A reação em cadeia da polimerase (PCR) tem seu emprego restrito na rotina diagnóstica pela necessidade de infra-estrutura adequada, facilidade de contaminação e custo elevado. Paralelamente, a variabilidade de resultados pela PCR observados em diferentes regiões do Brasil suscita questões relativas à sua aplicação ao diagnóstico. Sua alta especificidade aponta para sua aplicação como método confirmatório no diagnóstico de pacientes com provas sorológicas duvidosas e como método auxiliar no controle pós-terapêutico da doença crônica em comparação às técnicas sorológicas e parasitológicas. O objetivo do trabalho foi discutir e comparar a aplicação dos métodos moleculares e parasitológicos indiretos no diagnóstico e controle pós-terapêutico da doença de Chagas crônica, com base na literatura publicada no período de 1954-2001

Perfil de pacientes que evoluem para óbito por tuberculose no município de São Paulo, 2002

OBJECTIVE: To profile adult patients dying of tuberculosis in the city of São Paulo with respect to biological, environmental and institutional factors. METHODS: Descriptive study covering all tuberculosis deaths (N=416) among individuals aged over 15 years in 2002. Data were obtained from hospital records, the local Mortality Information System, Coroner's Service, and tuberculosis Surveillance System. The estimates of relative risk and 95% confidence intervals (95% CI) were based on the reference group, i.e., females aged 15 to 29 years, originally from the State of São Paulo (Brazil). A comparative analysis was conducted using Pearson's chi-square test and Fisher's exact test for categorical variables and Kruskal-Wallis test for continuous variables. RESULTS: Of all tuberculosis deaths identified, 78% had pulmonary form. Tuberculosis diagnosis was made after death in 30% and in primary health care units in 14%. Of them, 44% had not started treatment; 49% were not notified; and 76% were men. The median age was 51 years; 52% had up to four years of schooling; 4% were probably living in the streets. Mortality rate increased with age; it was 5.0/100,000 for the entire city, ranging between zero to 35 according to the district. Previous treatment was reported for 82 out of 232 patients, and of them, 41 defaulted treatment. Diabetes (16%), chronic obstructive pulmonary disease (19%), HIV infection (11%), smoking (71%), and alcohol abuse (64%) were also reported. CONCLUSIONS: Adult males over 50, migrants and living in lower Human Development Index districts were more likely to die of tuberculosis. Low schooling and comorbidities are relevant characteristics. Low involvement of primary care units in tuberculosis diagnosis and high underreporting of cases were also seen.OBJETIVO: Describir el perfil de pacientes adultos residentes en el municipio de São Paulo (Sureste de Brasil) que evolucionaron a óbito asociado con tuberculosis, según factores biológicos, ambientales e institucionales. MÉTODOS: Se realizó estudio descriptivo, abarcando todos los óbitos por tuberculosis (N=416) ocurridos en 2002, entre mayores de 15 años. Los datos analizados fueron obtenidos del Sistema Municipal de Informaciones de Mortalidad, prontuarios hospitalares, Servicio de Verificación de Óbitos y Sistema de Vigilancia de Tuberculosis. Los cálculos de riesgos relativos e intervalos de confianza de 95% (IC 95%) tuvieron como referencia el sexo femenino, grupo de 15 a 29 años, y los naturales del Estado de Sao Paulo. El análisis comparativo uso la prueba de Chi-cuadrado de Pearson y el exacto de Fisher para variables categóricas y la prueba de Kruskal-Wallis para variables continuas. RESULTADOS: Del total de óbitos, 78% presentaron la forma pulmonar; el diagnóstico fue efectuado posterior a la muerte en 30% y en unidades de atención primaria en 14% de los casos; 44% no iniciaron tratamiento; 49% no fueron notificados; 76% eran hombres y la edad mediana fue de 51 años; 52% tenían cuatro años de estudio, 4% probablemente vivían en las calles. Las tasas de mortalidad aumentaban con la edad, con un valor de 5,0/100.000 en el municipio, variando de cero a 35, dependiendo del distrito. Para 82 de 232 pacientes con registro de tratamiento, había registro de tratamiento anterior, y de esos, 41 lo habían abandonado. Se comprobó presencia de diabetes (16%), enfermedad pulmonar obstructiva crónica (19%), HIV (11%), tabaquismo (71%) y alcoholismo (64%) en los pacientes. CONCLUSIONES: Los hombres por encima de los 50 años, migrantes y residentes en distritos con bajo Índice de Desarrollo Humano presentaron mayores riesgos de óbito. La baja escolaridad y presentar co-morbilidad son características importantes. Se observo baja participación de las unidades básicas de salud en el diagnóstico y una elevada sub-notificación.OBJETIVO: Descrever o perfil de pacientes adultos residentes no município de São Paulo que evoluíram para óbito associado à tuberculose, segundo fatores biológicos, ambientais e institucionais. MÉTODOS: Estudo descritivo, abrangendo todos os óbitos por tuberculose (N=416) ocorridos em 2002, entre maiores de 15 anos. Os dados analisados foram obtidos do Sistema Municipal de Informações de Mortalidade, prontuários hospitalares, Serviço de Verificação de Óbitos e Sistema de Vigilância de Tuberculose. Os cálculos dos riscos relativos e intervalos de confiança de 95% (IC 95%) tiveram como referência o sexo feminino, grupo de 15 a 29 anos, e os naturais do Estado de São Paulo. A análise comparativa usou o teste do qui-quadrado de Pearson e o exato de Fisher para variáveis categóricas e o teste Kruskal-Wallis para variáveis contínuas. RESULTADOS: Do total de óbitos, 78% apresentavam a forma pulmonar; o diagnóstico foi efetuado após a morte em 30% e em unidades de atendimento primário em 14% dos casos; 44% não iniciaram tratamento; 49% não foram notificados; 76% eram homens e a mediana da idade foi de 51 anos; 52% tinham até quatro anos de estudo, 4% eram prováveis moradores de rua. As taxas de mortalidade aumentavam com a idade, sendo de 5,0/100.000 no município, variando de zero a 35, conforme o distrito. Para 82 de 232 pacientes com registro de tratamento, havia referência de tratamento anterior, e desses, 41 o haviam abandonado. Constatou-se presença de diabetes (16%), doença pulmonar obstrutiva crônica (19%), HIV (11%), tabagismo (71%) e alcoolismo (64%) nos pacientes. CONCLUSÕES: Homens acima de 50 anos, migrantes e residentes em distritos com baixo Índice de Desenvolvimento Humano apresentam maiores riscos de óbito. A pouca escolaridade e apresentar co-morbidades são características importantes. Observou-se baixa participação das unidades básicas de saúde no diagnóstico e a elevada sub-notificação

Previous BCG vaccination is associated with less severe clinical progression of COVID-19

Background: BCG vaccination, originally used to prevent tuberculosis, is known to “train” the immune system to improve defence against viral respiratory infections. We investigated whether a previous BCG vaccination is associated with less severe clinical progression of COVID-19./ Methods: A case-control study comparing the proportion with a BCG vaccine scar (indicating previous vaccination) in cases and controls presenting with COVID-19 to health units in Brazil. Cases were subjects with severe COVID-19 (O2 saturation < 90%, severe respiratory effort, severe pneumonia, severe acute respiratory syndrome, sepsis, and septic shock). Controls had COVID-19 not meeting the definition of “severe” above. Unconditional regression was used to estimate vaccine protection against clinical progression to severe disease, with strict control for age, comorbidity, sex, educational level, race/colour, and municipality. Internal matching and conditional regression were used for sensitivity analysis./ Results: BCG was associated with high protection against COVID-19 clinical progression, over 87% (95% CI 74–93%) in subjects aged 60 or less and 35% (95% CI − 44–71%) in older subjects./ Conclusions: This protection may be relevant for public health in settings where COVID-19 vaccine coverage is still low and may have implications for research to identify vaccine candidates for COVID-19 that are broadly protective against mortality from future variants. Further research into the immunomodulatory effects of BCG may inform COVID-19 therapeutic research.

Previous BCG vaccination is associated with less severe clinical progression of COVID-19

BACKGROUND: BCG vaccination, originally used to prevent tuberculosis, is known to "train" the immune system to improve defence against viral respiratory infections. We investigated whether a previous BCG vaccination is associated with less severe clinical progression of COVID-19 METHODS: A case-control study comparing the proportion with a BCG vaccine scar (indicating previous vaccination) in cases and controls presenting with COVID-19 to health units in Brazil. Cases were subjects with severe COVID-19 (O2 saturation < 90%, severe respiratory effort, severe pneumonia, severe acute respiratory syndrome, sepsis, and septic shock). Controls had COVID-19 not meeting the definition of "severe" above. Unconditional regression was used to estimate vaccine protection against clinical progression to severe disease, with strict control for age, comorbidity, sex, educational level, race/colour, and municipality. Internal matching and conditional regression were used for sensitivity analysis. RESULTS: BCG was associated with high protection against COVID-19 clinical progression, over 87% (95% CI 74-93%) in subjects aged 60 or less and 35% (95% CI - 44-71%) in older subjects. CONCLUSIONS: This protection may be relevant for public health in settings where COVID-19 vaccine coverage is still low and may have implications for research to identify vaccine candidates for COVID-19 that are broadly protective against mortality from future variants. Further research into the immunomodulatory effects of BCG may inform COVID-19 therapeutic research

Doença de Chagas crônica: do xenodiagnóstico e hemocultura à reação em cadeia da polimerase

Embora tenham ocorrido aprimoramentos no diagnóstico parasitológico da doença de Chagas crônica, a baixa sensibilidade dos exames indiretos é uma limitação para sua aplicação ao diagnóstico e controle pós-terapêutico. A reação em cadeia da polimerase (PCR) tem seu emprego restrito na rotina diagnóstica pela necessidade de infra-estrutura adequada, facilidade de contaminação e custo elevado. Paralelamente, a variabilidade de resultados pela PCR observados em diferentes regiões do Brasil suscita questões relativas à sua aplicação ao diagnóstico. Sua alta especificidade aponta para sua aplicação como método confirmatório no diagnóstico de pacientes com provas sorológicas duvidosas e como método auxiliar no controle pós-terapêutico da doença crônica em comparação às técnicas sorológicas e parasitológicas. O objetivo do trabalho foi discutir e comparar a aplicação dos métodos moleculares e parasitológicos indiretos no diagnóstico e controle pós-terapêutico da doença de Chagas crônica, com base na literatura publicada no período de 1954-2001

Profile of tuberculosis patients progressing to death, city of São Paulo, Brazil, 2002.

OBJECTIVE: To profile adult patients dying of tuberculosis in the city of São Paulo with respect to biological, environmental and institutional factors. METHODS: Descriptive study covering all tuberculosis deaths (N=416) among individuals aged over 15 years in 2002. Data were obtained from hospital records, the local Mortality Information System, Coroner's Service, and tuberculosis Surveillance System. The estimates of relative risk and 95% confidence intervals (95% CI) were based on the reference group, i.e., females aged 15 to 29 years, originally from the State of São Paulo (Brazil). A comparative analysis was conducted using Pearson's chi-square test and Fisher's exact test for categorical variables and Kruskal-Wallis test for continuous variables. RESULTS: Of all tuberculosis deaths identified, 78% had pulmonary form. Tuberculosis diagnosis was made after death in 30% and in primary health care units in 14%. Of them, 44% had not started treatment; 49% were not notified; and 76% were men. The median age was 51 years; 52% had up to four years of schooling; 4% were probably living in the streets. Mortality rate increased with age; it was 5.0/100,000 for the entire city, ranging between zero to 35 according to the district. Previous treatment was reported for 82 out of 232 patients, and of them, 41 defaulted treatment. Diabetes (16%), chronic obstructive pulmonary disease (19%), HIV infection (11%), smoking (71%), and alcohol abuse (64%) were also reported. CONCLUSIONS: Adult males over 50, migrants and living in lower Human Development Index districts were more likely to die of tuberculosis. Low schooling and comorbidities are relevant characteristics. Low involvement of primary care units in tuberculosis diagnosis and high underreporting of cases were also seen