INTRODUCTION: In Rio de Janeiro, in almost half of the cases of pleural tuberculosis (PT) treatment begins without substantiation of diagnosis. We examined variables associated with this disease. METHOD: We studied 215 consecutive patients; 104 had tuberculosis (TB) and 111 did not (NTB): 41 neoplasms, 29 transudates, 28 para-pneumonic and 13 other etiologies. Clinical and laboratory variables were assessed in ...