Purpose: Investigation on the influence of early start of chemotherapy on the results of sputum smear and culture (Ogawa medium and BACTEC MGIT960).
Object and method: Retrospective study for tubercle bacilli positive pulmonary tuberculosis cases in our hospital.
Result: Starting chemotherapy before the completion of pretreatment sputum examination was found to have no adverse effect on smear positive rate and smear positive grade (246 cases), culture contamination rate on Ogawa medium and BACTEC MGIT960 (1128 sputums), culture positive rate and culture positive grade/time to confirm positive on Ogawa medium (245 cases), and culture positive rate on BACTEC MGIT960 (239 cases). Time to confirm positive on BACTEC MGIT960 was slightly, but significantly prolonged (1.16 days delay in cases with 1-3 days chemotherapy [228 cases], and 4.01 days delay in cases with 4-6 days chemotherapy [59 cases]).
Conclusion: Unfluence of early start of chemotherapy on the results of sputum smear and culture is minor. In most of bacilli positive pulmonary tuberculosis cases chemotherapy can be started before the completion of pretreatment sputum examination.