a group of 250 patients with new or enlarging apical lung lesions which were thought to be tuberculous , and who had positive tuberculin tests but negative sputum smears and cultures for mycobacterium tuberculosis , were treated with an ultrashort ( 3-month ) , 4-drug ( rifampicin , isoniazid , pyrazinamide and ethambutol ) regimen .
C0041296
tuberculous
C0034239
pyrazinamide