Evaluation of a western blot serum test for the diag-

Evaluation of a western blot serum test for the diagnosis of Mycobacterium tuberculosis infection. E. Rovatti, M.P. Corradi, M. Amicosante, P.L. Tartoni, W. Panini, A. Ancora, A.M. Cenci, L. Zucchi, L. Monno, G. Angarano, C. Saltini. ERS Journals Ltd 1996. ABSTRACT: This study was designed to evaluate the possibility of monitoring Mycobacterium tuberculosis infection using a serological assay. A discriminant score comprising antigen fractions of 38, 28, 24 and 19 kDa, identified in western blots using the Mycobacterium bovis bacille Calmette-Guérin (BCG) A60 antigen complex was established in a sample of 57 purified protein derivative (PPD)-negative and 47 PPD-positive individuals. It was then tested in a group of 140 subjects undergoing BCG vaccination as a model of tuberculosis complex infection and in a group of human immunodeficiency virus (HIV)-infected individuals as a model of cell-mediated immunodeficiency-related risk of tuberculosis. The discriminant score identified 57 out of 57 (100%) PPD-positives and none (0%) of the 47 PPD-negatives. In the BCG vaccinated subjects, 1.4% tested positive before vaccination and 90% after vaccination. In the HIV-positive subjects, 90% of the PPD-positive and 5% of the PPD-negative subjects had a positive score. This study suggests that the western blot discriminant score is an accurate test to survey M. tuberculosis infection in serum samples. Eur Respir J., 1996, 9, 288–292. *Dipartimento di Scienze Mediche, Oncologiche e Radiologiche, Sezione di Malattie dell'Apparato Respiratorio e Fisiopatologia Respiratoria, Università di Modena, Italy. **Direzione Sanitaria, Azienda Ospedaliera di Modena, Italy. +Dipartimento di Scienze Biomediche, Cattedra di Biometria e Statistica Medica, Università di Modena, Italy. ++Centro Pneumologico, Azienda USL Modena, Italy. #Ospedale di Castelfranco Emilia, Azienda USL Modena, Italy. ##Clinica di Malattie Infettive, Università di Bari, Italy. Correspondence: C. Saltini, Dipartimento di Scienze Mediche Oncologiche e Radiologiche Sezione di Malattie dell'Apparato Respiratorio e Fisiopatologia Respiratoria via del Pozzo 71, 41100 Modena, Italy