title: Comparison of serological responses in two different populations with pulmonary tuberculosis.
abstract: Observational studies on the humoural immune responses of the Warao indigenous people from Delta Amacuro, an isolated area, were compared with urban residents of the Venezuelan capital. Mycobacterium tuberculosis-specific reactivities (IgM, IgE, sIgA, IgG and IgG subclasses) were measured by ELISA using PPD and 38-kDa M. tuberculosis antigens. A total of 294 individuals were studied, 162 Warao (indigenous people) and 132 Creole (non-indigenous people). The patient group consisted of 87 Warao patients and 58 Creole patients, while the control group consisted of 75 Warao controls and 74 Creole controls. Combinations among the isotypes studied were performed. The findings showed that for the Warao people, sensitivity to the combination including anti-PPD IgG and IgE was 92.0%, while for the Creole people, sensitivity to the combination including anti-PPD IgG but more so anti-PPD IgG1 and IgG2 was 90.0%. Simple tests were able to show higher specificities, which were population-specific; specificities were anti-PPD IgG3, 100.0% and anti-PPD IgM, 97.4% for the Warao and Creole peoples, respectively. In conclusion, while simple tests reached high specificity, the multi-isotype tests improved sensitivity; the latter shows this approach may be useful in diagnostic testing.
authors.affiliation: Laboratorio de Inmunología de Enfermedades Infecciosas, Instituto de Biomedicina, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela. zaraujogarcia@yahoo.com
authors.forename: Zaida
authors.initials: Z
authors.lastname: Araujo
authors.forename: Francesca
authors.initials: F
authors.lastname: Giampietro
authors.forename: Lucio Castellano
authors.initials: LC
authors.lastname: Cançado
authors.forename: Mahavir
authors.initials: M
authors.lastname: Singh
authors.forename: Albina
authors.initials: A
authors.lastname: Wide
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology*; D000937:Antigen-Antibody Reactions; D000942:Antigens, Bacterial / Q000276:immunology*; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology*; D007199:Indians, South American; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D011446:Prospective Studies; D014374:Tuberculin Test; D014397:Tuberculosis, Pulmonary / Q000208:ethnology / Q000276:immunology*; D014505:Urban Population; D014687:Venezuela / Q000208:ethnology; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D007074:Immunoglobulin G; C072681:Mycobacterium tuberculosis antigens; D007073:Immunoglobulin E