Duration of Pulmonary Tuberculosis Infectiousness under Adequate Therapy, as Assessed Using Induced Sputum Samples.
- Author:
Yousang KO
1
;
Jeong Hwan SHIN
;
Hyun Kyung LEE
;
Young Seok LEE
;
Suh Young LEE
;
So Young PARK
;
Eun Kyung MO
;
Changhwan KIM
;
Yong Bum PARK
Author Information
- Publication Type:Original Article
- Keywords: Tuberculosis, Pulmonary; Mycobacterium tuberculosis; Infectious Disease Incubation Period; Induced Sputum
- MeSH: Cohort Studies; Drug Therapy; Humans; Infectious Disease Incubation Period; Mycobacterium tuberculosis; Retrospective Studies; Sputum*; Tuberculosis, Pulmonary*
- From:Tuberculosis and Respiratory Diseases 2017;80(1):27-34
- CountryRepublic of Korea
- Language:English
- Abstract: BACKGROUND: A sputum culture is the most reliable indicator of the infectiousness of pulmonary tuberculosis (PTB); however, a spontaneous sputum specimen may not be suitable. The aim of this study was to evaluate the infectious period in patients with non–drug-resistant (DR) PTB receiving adequate standard chemotherapy, using induced sputum (IS) specimens. METHODS: We evaluated the duration of infectiousness of PTB using a retrospective cohort design. RESULTS: Among the 35 patients with PTB, 22 were smear-positive. The rates of IS culture positivity from baseline to the sixth week of anti-tuberculosis medication in the smear-positive PTB group were 100%, 100%, 91%, 73%, 36%, and 18%, respectively. For smear-positive PTB cases, the median time of conversion to culture negativity was 35.0 days (range, 28.0–42.0 days). In the smear-negative PTB group (n=13), the weekly rates of positive IS culture were 100%, 77%, 39%, 8%, 0%, and 0%, respectively, and the median time to conversion to culture-negative was 21.0 days (range, 17.5–28.0 days). CONCLUSION: The infectiousness of PTB, under adequate therapy, may persist longer than previously reported, even in patients with non-DR PTB.