RESUMO
Specific immunoglobulin (IgA, IgG and IgM) responses to different antigen targets (soluble eggs antigen--SEA, soluble worm adult protein--SWAP and keyhole limpet hole--KLH) were measured by enzyme linked immunosorbent assay (ELISA) in patients with acute and chronic schistosomiasis, as well as patients without schistosomiasis. SEA IgA and KLH IgM presented high discriminatory powers to distinguish acute from chronic schistosomiasis, with calculated areas under the curve (AUCs) of 0.88 and 0.82, respectively, obtained from receiver operating characteristic (ROC) curve. On the other hand, these tests, particularly SEA IgA were not useful to distinguish schistosomiasis (including the acute and chronic forms) from individuals without this disease, but infected with other intestinal parasites (Ascaris lumbricoides, Trichuris trichiura and hookworm). By contrast, SWAP IgG and SEA IgG were able to discriminate schistosomiasis patients from healthy individuals and patients infected with other parasites (AUCs of 0.96 and 0.85, respectively). Thus, it is possible to use a combination of serological tests, such as SEA IgA and SWAP IgG, to simultaneously establish the diagnosis of schistosomiasis and discriminate the acute from the chronic forms of the disease.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Esquistossomose mansoni/diagnóstico , Adolescente , Adulto , Idoso , Animais , Antígenos de Helmintos , Área Sob a Curva , Criança , Pré-Escolar , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Curva ROCRESUMO
The aim of this work was to study the difference in interferon gamma (IFN-gamma) production by T lymphocytes after early secretory antigen target 6 (ESAT-6) or purified protein derivate (PPD) stimulation in whole blood culture supernatants from children with suspected tuberculosis (TB) disease (n = 21), latent TB infection (n = 16) and negative controls (NC) (n = 22) from an endemic area in Brazil. The concentration of IFN-gamma (pg/ml) was measured by enzyme linked immunosorbent assay and the differences in the IFN-gamma levels for each group were compared and evaluated using an unpaired Student's t-test; p values < 0.05 were considered significant. Measurement of IFN-gamma levels after ESAT-6 stimulation raised the possibility of early diagnosis in the latent TB group (p = 0.0030). Nevertheless, the same group showed similar responses to the NC group (p > 0.05) after PPD stimulation. The IFN-gamma assay using ESAT-6 as an antigenic stimulus has the potential to be used as a tool for the immunodiagnosis of early TB in children.
Assuntos
Antígenos de Bactérias , Proteínas de Bactérias , Interferon gama/biossíntese , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/diagnóstico , Adolescente , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Tuberculose Pulmonar/imunologiaRESUMO
The aim of this work was to study the difference in interferon gamma (IFN-gamma) production by T lymphocytes after early secretory antigen target 6 (ESAT-6) or purified protein derivate (PPD) stimulation in whole blood culture supernatants from children with suspected tuberculosis (TB) disease (n = 21), latent TB infection (n = 16) and negative controls (NC) (n = 22) from an endemic area in Brazil. The concentration of IFN-gamma (pg/ml) was measured by enzyme linked immunosorbent assay and the differences in the IFN-gamma levels for each group were compared and evaluated using an unpaired Student's t-test; p values < 0.05 were considered significant. Measurement of IFN-gamma levels after ESAT-6 stimulation raised the possibility of early diagnosis in the latent TB group (p = 0.0030). Nevertheless, the same group showed similar responses to the NC group (p > 0.05) after PPD stimulation. The IFN-gamma assay using ESAT-6 as an antigenic stimulus has the potential to be used as a tool for the immunodiagnosis of early TB in children.
Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Antígenos de Bactérias , Proteínas de Bactérias , Interferon gama/biossíntese , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/diagnóstico , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Sensibilidade e Especificidade , Tuberculose Pulmonar/imunologiaRESUMO
Specific IgG and IgM responses to soluble egg antigen (SEA) and keyhole limpet haemocyanin (KLH) were measured by ELISA in patients with acute and chronic schistosomiasis. The tests based upon IgM and IgG antibodies responses to KLH presented the best diagnostic discrimination, and can be used in conjunction with clinical and epidemiological data to the differential diagnosis of acute schistosomiasis.
Assuntos
Antígenos de Helmintos/sangue , Proteínas de Helminto/sangue , Hemocianinas/imunologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/diagnóstico , Doença Aguda , Animais , Anticorpos Anti-Helmínticos/imunologia , Biomarcadores/sangue , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Hemocianinas/análise , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Esquistossomose mansoni/sangue , Sensibilidade e EspecificidadeRESUMO
Specific IgG and IgM responses to soluble egg antigen (SEA) and keyhole limpet haemocyanin (KLH) were measured by ELISA in patients with acute and chronic schistosomiasis. The tests based upon IgM and IgG antibodies responses to KLH presented the best diagnostic discrimination, and can be used in conjunction with clinical and epidemiological data to the differential diagnosis of acute schistosomiasis.
