Prospective multicentre study on the evaluation of antituberculosis treatment results in Italy: comparison of the culture- versus the smear-based methods

Cohort analysis of treatment outcomes is the most informative technique to evaluate the tuberculosis (TB) control programme. The aim of the study was to assess treatment outcomes comparing the smear-versus the culture-based m ethods, using data on TB patients treated under programme conditions in Ita ly. This was a prospective monitoring study based on the standardized collectio n of forms from a representative sample of Italian TB Units. The forms, wit h individual data, were reviewed and analysed on a quarterly basis accordin g to the principles of cohort analysis, using both the smear- and culture-b ased methods. The complete bacteriological profile of patients was analysed at diagnosis and at completion of treatment. Nine hundred and ninety-two TB cases were notified, Among 681 pulmonary cas es, 368 cases were culture-confirmed at diagnosis (333 new and 35 retreatme nt cases, 293 being sputum smear positive, 79.6%). At the end of treatment, out of the 333 new culture-confirmed cases, 136 (40.8%) were defined "cure d" using the culture-based method and 108 (32.3%) using the smear-based met hod (p<0.05, chi(2) test), The culture-based method is the recommended tool to evaluate pulmonary tube rculosis treatment results. Culture allows a more precise definition of a " cured" patient in both sputum smear positive and negative tuberculosis case s.