Infection and Drug Resistance (Apr 2022)

Inducible Resistance to Amikacin in Mycobacterium abscessus Isolated in Beijing, China

  • Zhang Z,
  • Wang W,
  • Wang Y,
  • Xue Z,
  • Li S,
  • Pang Y

Journal volume & issue
Vol. Volume 15
pp. 2287 – 2291

Abstract

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Zhijian Zhang,1,* Wei Wang,2,* Yufeng Wang,3 Zhongtan Xue,3 Shanshan Li,2 Yu Pang2 1Department of Respiratory and Critical Care Medicine, the Second Medical Center of Chinese PLA General Hospital, Beijing, 100036, People’s Republic of China; 2Department of Bacteriology and Immunology, Beijing Key Laboratory on Drug-Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute/Beijing Chest Hospital, Capital Medical University, Beijing, 101149, People’s Republic of China; 3Innovation Alliance on Tuberculosis Diagnosis and Treatment, Beijing, 101149, People’s Republic of China*These authors contributed equally to this workCorrespondence: Shanshan Li; Yu Pang, Department of Bacteriology and Immunology, Beijing Key Laboratory on Drug-Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute/Beijing Chest Hospital, Capital Medical University, Beijing, 101149, People’s Republic of China, Tel +86-010-89509368 ; +86-010-89509162, Email [email protected]; [email protected]: We aimed to determine the prevalence of amikacin (AMK) resistance of clinical Mycobacterium abscessus (MAB) isolates and to investigate if AMK resistance was induced by AMK exposure. A total of 75 MAB isolates underwent susceptibility testing for AMK after 3 and 14 days of incubation, respectively. The partial fragment of the rrs gene conferring AMK resistance was sequenced. The MIC values for AMK ranged from 0.5 to 128 μg/mL, with MIC50 and MIC90 values of 2 and 32 μg/mL, respectively. In addition, 9.3% of isolates (7/75) were resistant to AMK, all of which harbored a mutation within the rrs locus, including six with A1408G mutation and one with a C1409T mutation. Of note, the MICs of three isolates were significantly increased from 2 μg/mL to 64 μg/mL (one isolate) and 2 μg/mL to 128 μg/mL (two isolates), suggesting that three of the MAB isolates had inducible resistance to AMK. In conclusion, our data demonstrate that approximately one-tenth of clinical MAB isolates in Beijing harbored AMK resistance due to the acquisition of rrs mutations. Additionally, we firstly identified that intrinsic AMK resistance is inducible in MAB isolates, highlighting the urgent need to establish a proper method for the in vitro detection of AMK susceptibility in MAB.Keywords: amikacin, intrinsic resistance, inducible, Mycobacterium abscessus

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