Guan Liu1, Gui-Rong Wang1, Xia Yu1, Qian Liang1, Jing Mu1, Yuan-Yuan Shang1, Ying Ling1, Hai-Qing Zhang1, Su-Hua Zheng2, Hai-Rong Huang3. 1. National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory on Drug-Resistant Tuberculosis, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing 101149, People's Republic of China. 2. National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory on Drug-Resistant Tuberculosis, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing 101149, People's Republic of China. Electronic address: suhuazheng0264@sina.com. 3. National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory on Drug-Resistant Tuberculosis, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing 101149, People's Republic of China. Electronic address: hairong.huangcn@gmail.com.
Abstract
BACKGROUND: A Mycobacterium parascrofulaceum strain was isolated from a pneumonia patient-the first such reported case from China. The bacteriological characteristics of the strain were determined. METHODS: Species identification was performed by homologue gene sequence comparison, then a series of biochemical tests was conducted to elucidate the bacteriological characteristics. Drug susceptibility and pathogenicity to mice of the strain were tested. RESULTS: The clinical M. parascrofulaceum strain presented a very similar phenotypic profile to that of Mycobacterium scrofulaceum. The M. parascrofulaceum strain was sensitive to rifabutin, rifapentine, clarithromycin, azithromycin, cefoxitin, and moxifloxacin in vitro. At week 2 post-infection, the lung tissues of mice demonstrated a local inflammatory response denoted by peri-bronchiolar inflammatory infiltrates. At weeks 4 and 8, the lung tissues showed peri-bronchiolar inflammatory infiltrates with large aggregates of lymphocytes and part of the tissue showed granulomatous lesions; there was no appreciable necrosis. The colony-forming units (CFU) count of infected lung and spleen increased gradually during the 8 weeks of the experiment. CONCLUSIONS: The M. parascrofulaceum strain isolated in China was sensitive to rifabutin, rifapentine, clarithromycin, azithromycin, cefoxitin, and moxifloxacin. The mycobacteria were capable of proliferating in mice and could lead to pathological changes in the lungs of the mice.
BACKGROUND: A Mycobacterium parascrofulaceum strain was isolated from a pneumoniapatient-the first such reported case from China. The bacteriological characteristics of the strain were determined. METHODS: Species identification was performed by homologue gene sequence comparison, then a series of biochemical tests was conducted to elucidate the bacteriological characteristics. Drug susceptibility and pathogenicity to mice of the strain were tested. RESULTS: The clinical M. parascrofulaceum strain presented a very similar phenotypic profile to that of Mycobacterium scrofulaceum. The M. parascrofulaceum strain was sensitive to rifabutin, rifapentine, clarithromycin, azithromycin, cefoxitin, and moxifloxacin in vitro. At week 2 post-infection, the lung tissues of mice demonstrated a local inflammatory response denoted by peri-bronchiolar inflammatory infiltrates. At weeks 4 and 8, the lung tissues showed peri-bronchiolar inflammatory infiltrates with large aggregates of lymphocytes and part of the tissue showed granulomatous lesions; there was no appreciable necrosis. The colony-forming units (CFU) count of infected lung and spleen increased gradually during the 8 weeks of the experiment. CONCLUSIONS: The M. parascrofulaceum strain isolated in China was sensitive to rifabutin, rifapentine, clarithromycin, azithromycin, cefoxitin, and moxifloxacin. The mycobacteria were capable of proliferating in mice and could lead to pathological changes in the lungs of the mice.