Diagnostic performances of the ALS assay by using single TB specific antigens and simultaneous determination of these antigens in various combinations.

BCG vaccine- glutamate-BCG vaccine for intradermal use, lot 1861, Japan BCG Laboratories, Japan; CFP10-ESAT6-A- fusion protein of Culture filtrate protein-10 and Early secretory antigenic target-6; TB51A, TB15.3 antigens from RD1 region; CFP- culture filtrate proteins and CW− cell wall fraction from M. tuberculosis H37Rv and clinical isolate CSU93; LAM− lipoarabinomannan of M. tuberculosis H37Rv. ALS titers are given from 48 hrs culture. Receiver-operator characteristic curves were constructed from the ALS responses to all antigens, comparing TB patients with non-TB patients to select the best cutoff point at which the accuracy was maximum for each antigen. The cut-off values for all antigens were very close (0.408 to 0.423) except for CFP10-ESAT6-A (0.397). All patients could not be tested for all 7 antigens because in some cases we did not have enough ALS supernatant.