title: Bacteriological and virulence study of a Mycobacterium chimaera isolate from a patient in China.
abstract: A clinical isolate from a patient was identified as Mycobacterium chimaera, a recently identified species of nontuberculous Mycobacteria. The biochemical and molecular identity, drug sensitivity and virulence of this isolated strain were investigated. 16S rRNA, the 16S-23S ITS, hsp65 and rpoB were amplified, and their sequence similarities with other mycobacteria were analyzed. The minimum inhibitory concentrations of 22 anti-microbial agents against this isolate were established, and the virulence of the isolate was evaluated by intravenous injection into C57BL/6 mice using Mycobacterium tuberculosis H37Rv as a control strain. Growth and morphological characteristics and mycolic acid profile analysis revealed that this isolated strain was a member of the Mycobacterium avium complex. BLAST analysis of the amplified sequences showed that the isolated strain was closely related to M. chimaera. Susceptibility testing showed that the isolate was sensitive to rifabutin, rifapentine, clarithromycin, azithromycin, imipenem and cefoxitin. Bacterial load determination and tissue histopathology of the infected mice indicated that the isolate was highly virulent. The first case of M. chimaera infection in China was evaluated. The information derived from this case may offer valuable guidance for clinical diagnosis and treatment.
authors.affiliation: National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory on Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, 101149, China.
authors.forename: Guan
authors.initials: G
authors.lastname: Liu
authors.forename: Su-Ting
authors.initials: ST
authors.lastname: Chen
authors.forename: Xia
authors.initials: X
authors.lastname: Yu
authors.forename: Yu-Xun
authors.initials: YX
authors.lastname: Li
authors.forename: Ying
authors.initials: Y
authors.lastname: Ling
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Dong
authors.forename: Su-Hua
authors.initials: SH
authors.lastname: Zheng
authors.forename: Hai-Rong
authors.initials: HR
authors.lastname: Huang
mesh_terms: D000328:Adult; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology; D058491:Bacterial Load; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D018834:Chaperonin 60 / Q000235:genetics; D002681:China; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D012321:DNA-Directed RNA Polymerases / Q000235:genetics; D004195:Disease Models, Animal; D006651:Histocytochemistry; D006801:Humans; D008168:Lung / Q000382:microbiology / Q000473:pathology; D008297:Male; D008810:Mice, Inbred C57BL; D008826:Microbial Sensitivity Tests; D009161:Mycobacterium / Q000145:classification* / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification*; D009165:Mycobacterium Infections, Nontuberculous / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014774:Virulence
chemical_list: D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D018834:Chaperonin 60; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S; C074119:heat-shock protein 65, Mycobacterium; D012321:DNA-Directed RNA Polymerases; C105078:RNA polymerase beta subunit