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. 1998 May;53(5):377–380. doi: 10.1136/thx.53.5.377

Detection of IgG and IgA against the mycobacterial antigen A60 in patients with extrapulmonary tuberculosis

M Alifano 1, R De Pascalis 1, M Sofia 1, S Faraone 1, M Del Pezzo 1, I Covelli 1
PMCID: PMC1745209  PMID: 9708230

Abstract

BACKGROUND—Diagnosis of extrapulmonary tuberculosis is often difficult to establish using standard methods. Serological techniques based on detection of antibodies against mycobacterial antigen A60 have shown good sensitivity and specificity in pulmonary tuberculosis. The present study was undertaken to define the diagnostic accuracy of testing for IgG and IgA against A60 in extrapulmonary tuberculosis.
METHODS—One hundred and ninety eight subjects were studied: 42 patients with extrapulmonary tuberculosis confirmed by microbiology and/or histology, 24 subjects with healed pulmonary or extrapulmonary tuberculosis, 44 patients with a defined non-tuberculous disease, and 88 healthy volunteers (44 PPD negative and 44 PPD positive). Detection of IgG and IgA against A60 antigen was carried out by enzyme-linked immunosorbent assay. Cut off values were determined by receiver operating characteristic curves.
RESULTS—Sensitivity of the IgG test was 73.8% in extrapulmonary tuberculosis, while the specificity was 96.1%. The IgA test showed a sensitivity of 69.0% with a specificity of 93.6%. Combination of the IgG and IgA tests showed a sensitivity of 80.9% and a specificity of 92.3%. Patients with extrapulmonary tuberculosis showed significantly higher titres of both IgG and IgA against A60 than other groups.
CONCLUSIONS—Anti-A60 IgG or IgA tests are characterised by good sensitivity and specificity. The combined use of both tests allows an increase in diagnostic accuracy of extrapulmonary tuberculosis.



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Selected References

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  1. Alifano M., De Pascalis R., Sofia M., Faraone S., Del Pezzo M., Covelli I. Evaluation of IgA-mediated humoral immune response against the mycobacterial antigen P-90 in diagnosis of pulmonary tuberculosis. Chest. 1997 Mar;111(3):601–605. doi: 10.1378/chest.111.3.601. [DOI] [PubMed] [Google Scholar]
  2. Alifano M., Sofia M., Mormile M., Micco A., Mormile A. F., Del Pezzo M., Carratù L. IgA immune response against the mycobacterial antigen A60 in patients with active pulmonary tuberculosis. Respiration. 1996;63(5):292–297. doi: 10.1159/000196563. [DOI] [PubMed] [Google Scholar]
  3. Benjamin R. G., Daniel T. M. Serodiagnosis of tuberculosis using the enzyme-linked immunoabsorbent assay (ELISA) of antibody to Mycobacterium tuberculosis antigen 5. Am Rev Respir Dis. 1982 Dec;126(6):1013–1016. doi: 10.1164/arrd.1982.126.6.1013. [DOI] [PubMed] [Google Scholar]
  4. Brisson-Noel A., Aznar C., Chureau C., Nguyen S., Pierre C., Bartoli M., Bonete R., Pialoux G., Gicquel B., Garrigue G. Diagnosis of tuberculosis by DNA amplification in clinical practice evaluation. Lancet. 1991 Aug 10;338(8763):364–366. doi: 10.1016/0140-6736(91)90492-8. [DOI] [PubMed] [Google Scholar]
  5. Charpin D., Herbault H., Gevaudan M. J., Saadjian M., de Micco P., Arnaud A., Vervloet D., Charpin J. Value of ELISA using A60 antigen in the diagnosis of active pulmonary tuberculosis. Am Rev Respir Dis. 1990 Aug;142(2):380–384. doi: 10.1164/ajrccm/142.2.380. [DOI] [PubMed] [Google Scholar]
  6. Cocito C. G. Properties of the mycobacterial antigen complex A60 and its applications to the diagnosis and prognosis of tuberculosis. Chest. 1991 Dec;100(6):1687–1693. doi: 10.1378/chest.100.6.1687. [DOI] [PubMed] [Google Scholar]
  7. Dolberg O. T., Schlaeffer F., Greene V. W., Alkan M. L. Extrapulmonary tuberculosis in an immigrant society: clinical and demographic aspects of 92 cases. Rev Infect Dis. 1991 Jan-Feb;13(1):177–179. doi: 10.1093/clinids/12.5.177. [DOI] [PubMed] [Google Scholar]
  8. Gevaudan M. J., Bollet C., Charpin D., Mallet M. N., De Micco P. Serological response of tuberculosis patients to antigen 60 of BCG. Eur J Epidemiol. 1992 Sep;8(5):666–676. doi: 10.1007/BF00145382. [DOI] [PubMed] [Google Scholar]
  9. Gupta S., Kumari S., Banwalikar J. N., Gupta S. K. Diagnostic utility of the estimation of mycobacterial Antigen A60 specific immunoglobulins IgM, IgA and IgG in the sera of cases of adult human tuberculosis. Tuber Lung Dis. 1995 Oct;76(5):418–424. doi: 10.1016/0962-8479(95)90008-x. [DOI] [PubMed] [Google Scholar]
  10. Kennedy D. H., Fallon R. J. Tuberculous meningitis. JAMA. 1979 Jan 19;241(3):264–268. [PubMed] [Google Scholar]
  11. Manjunath N., Shankar P., Rajan L., Bhargava A., Saluja S., Shriniwas Evaluation of a polymerase chain reaction for the diagnosis of tuberculosis. Tubercle. 1991 Mar;72(1):21–27. doi: 10.1016/0041-3879(91)90020-s. [DOI] [PubMed] [Google Scholar]
  12. Metz C. E. Basic principles of ROC analysis. Semin Nucl Med. 1978 Oct;8(4):283–298. doi: 10.1016/s0001-2998(78)80014-2. [DOI] [PubMed] [Google Scholar]
  13. TAKAHASHI Y. Specific serum agglutination of kaolin particles sensitized with tubercle phosphatide and its clinical evaluation as a serodiagnostic test for tuberculosis. Am Rev Respir Dis. 1962 May;85:708–719. doi: 10.1164/arrd.1962.85.5.708. [DOI] [PubMed] [Google Scholar]
  14. Weir M. R., Thornton G. F. Extrapulmonary tuberculosis. Experience of a community hospital and review of the literature. Am J Med. 1985 Oct;79(4):467–478. doi: 10.1016/0002-9343(85)90034-8. [DOI] [PubMed] [Google Scholar]

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