SETTING: Royal Free Hospital, London. OBJECTIVE: To investigate the relationship between sputum mycobacterial load, assessed by time to positivity (TTP) in liquid culture, radiological cavitation and change in sputum bacterial load in response to anti-tuberculosis treatment. DESIGN: The study was conducted on 95 patients treated for sputum culture-positive pulmonary tuberculosis (TB), with pre-treatment TTP and baseline chest X-ray (CXR). Of these, 31 had chest computed tomography scans assessed for number and volume of cavities. The microbiological treatment response was measured in 56 patients with serial TTP, and related to baseline radiological cavitation. RESULTS: Cavitation was present in 48% of patients, and was associated with a shorter TTP at baseline (P < 0.001). Patients with more cavities and greater total cavitary volume had a shorter TTP (P < 0.001 for both). No difference was demonstrated in the rate of change in TTP on treatment (P = 0.36) between patients with and without cavities. CONCLUSION: This study confirms that cavitation is associated with higher baseline sputum mycobacterial load. The rate of decline in bacterial load in response to treatment is similar in patients with and without radiologically demonstrable cavities, suggesting that response to, and hence duration of, effective treatment may be predicted by the initial number of organisms present in the sputum.
SETTING: Royal Free Hospital, London. OBJECTIVE: To investigate the relationship between sputum mycobacterial load, assessed by time to positivity (TTP) in liquid culture, radiological cavitation and change in sputum bacterial load in response to anti-tuberculosis treatment. DESIGN: The study was conducted on 95 patients treated for sputum culture-positive pulmonary tuberculosis (TB), with pre-treatment TTP and baseline chest X-ray (CXR). Of these, 31 had chest computed tomography scans assessed for number and volume of cavities. The microbiological treatment response was measured in 56 patients with serial TTP, and related to baseline radiological cavitation. RESULTS: Cavitation was present in 48% of patients, and was associated with a shorter TTP at baseline (P < 0.001). Patients with more cavities and greater total cavitary volume had a shorter TTP (P < 0.001 for both). No difference was demonstrated in the rate of change in TTP on treatment (P = 0.36) between patients with and without cavities. CONCLUSION: This study confirms that cavitation is associated with higher baseline sputum mycobacterial load. The rate of decline in bacterial load in response to treatment is similar in patients with and without radiologically demonstrable cavities, suggesting that response to, and hence duration of, effective treatment may be predicted by the initial number of organisms present in the sputum.
Authors: Robert Blakemore; Pamela Nabeta; Amy L Davidow; Viral Vadwai; Rasim Tahirli; Vanisha Munsamy; Mark Nicol; Martin Jones; David H Persing; Doris Hillemann; Sabine Ruesch-Gerdes; Felicity Leisegang; Carlos Zamudio; Camilla Rodrigues; Catharina C Boehme; Mark D Perkins; David Alland Journal: Am J Respir Crit Care Med Date: 2011-11-01 Impact factor: 21.405
Authors: Colleen F Hanrahan; Grant Theron; Jean Bassett; Keertan Dheda; Lesley Scott; Wendy Stevens; Ian Sanne; Annelies Van Rie Journal: Am J Respir Crit Care Med Date: 2014-06-01 Impact factor: 21.405
Authors: Emmanuel Chigutsa; Kashyap Patel; Paolo Denti; Marianne Visser; Gary Maartens; Carl M J Kirkpatrick; Helen McIlleron; Mats O Karlsson Journal: Antimicrob Agents Chemother Date: 2012-11-26 Impact factor: 5.191