Cigarette smoking and culture conversion in patients with susceptible and M/XDR-TB.

BACKGROUND: Tuberculosis (TB) is a leading cause of morbidity and mortality worldwide. Active cigarette smoking may have a significant impact on treatment responses to anti-tuberculosis treatment. OBJECTIVE: To ascertain the effect of smoking on Mycobacterium tuberculosis sputum culture conversion rates following treatment initiation in patients with susceptible, multidrug-resistant and extensively drug-resistant TB (M/XDR-TB). METHOD: Sputum cultures of smoking and non-smoking patients with pulmonary TB (PTB) treated at a referral centre in Germany were evaluated. RESULTS: Between January 2012 and March 2017, 247 patients with PTB treated at the Medical Clinic of Research Center Borstel, Borstel, Germany, were included in the study. Of 247 patients, 65 (26.3%) were infected with multidrug-resistant strains of M. tuberculosis (MDR-TB). Sputum culture examinations were performed on a weekly basis. Active smoking (n = 111; time to culture conversion [TCC] 50.7 days, interquartile range [IQR] 26.5-73.0) and former smoking (n = 72; TCC 43.1 days, IQR 19.8-56.0) significantly delayed culture conversion rates (P < 0.001) when compared with never smoking (n = 64; TCC 33.2 days, IQR 8.0-50.3). Delay in TCC among smoking, non-MDR-TB patients (n = 138; TCC 47.3 days, IQR 19.0-89.0) was comparable with non-smoking, MDR-TB patients (n = 20; TCC 53.0 days, IQR 18.0-71.0). The shortest TCC was observed in non-smoking, non-MDR-TB patients (n = 44; TCC 33.0 days, IQR 10.0-48.5), whereas the longest was seen in smoking, MDR-TB patients (n = 45; TCC 60.7 days, IQR 33.3-89.0); P < 0.001). CONCLUSION: Active cigarette smoking and, to a lesser extent, former cigarette smoking, substantially delayed culture conversion in PTB.

Treatment responses in multidrug-resistant tuberculosis in Germany.

BACKGROUND: Excellent treatment outcomes have recently been reported for patients with multi/extensively drug-resistant tuberculosis (M/XDR-TB) in settings where optimal resources for individualised therapy are available. OBJECTIVE: To ascertain whether differences remain in treatment responses between patients with M/XDR-TB and those with non-M/XDR-TB. METHOD: Patients with TB were prospectively enrolled between March 2013 and March 2016 at five hospitals in Germany. Treatment was conducted following current guidelines and individualised on the basis of drug susceptibility testing. Two-month and 6-month sputum smear and sputum culture conversion rates were assessed. A clinical and radiological score were used to assess response to anti-tuberculosis treatment. RESULTS: Non-M/XDR-TB (n = 29) and M/XDR-TB (n = 46) patients showed similar rates of microbiological conversion: 2-month smear conversion rate, 90% vs. 78%; culture conversion rate, 67% vs. 61%; time to smear conversion, 19 days (IQR 10-32) vs. 31 days (IQR 14-56) (P = 0.066); time to culture conversion, 39 days (IQR 17-67) vs. 39 days (IQR 6-85) (P = 0.191). Both clinical and radiological scores decreased after the introduction of anti-tuberculosis treatment. CONCLUSION: There were no significant differences in scores between the two groups until 6 months of treatment. Under optimal clinical conditions, with the availability of novel diagnostics and a wide range of therapeutic options for individualised treatment, patients with M/XDR-TB achieved 6-month culture conversion rates that were compatible with those in patients with non-M/XDR-TB.