National Clinical Laboratory on Tuberculosis, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing Chest Hospital, Capital Medical University, Beijing, PR China.
Hebei Provincial Center for Clinical Laboratories, Second Hospital of Hebei Medical University, Shijiazhuang City, Hebei Province, PR China.
J Med Microbiol. 2022 Jun;71(6). doi: 10.1099/jmm.0.001549.
Nontuberculous mycobacteria (NTM) infections are increasing worldwide and are relatively resistant to many of the first- and second-line drugs to treat tuberculosis. Macrolide antibiotics, such as clarithromycin and azithromycin, are the key drugs for treating NTM infections. Fidaxomicin is a macrolide antibiotic that is widely used in treating infections, and has high activity against especially multidrug-resistant tuberculosis (MDR-TB) and has no cross-resistance with rifampicin. Fidaxomicin may have activity against NTM strains. To find that whether the macrolide antibiotic fidaxomicin has activity against NTM strains. Fidaxomicin used in this study was firstly tested on reference strains and has shown to be effective and workable. And then 28 rapidly growing mycobacteria (RGM), 12 slowly growing mycobacteria (SGM) reference strains and 103 NTM clinical isolates were tested by the microplate-based AlamarBlue assay (MABA) method to determine the MICs. Fidaxomicin, rifampicin and clarithromycin were tested against omplex subspecies 14 . and 5 . strains for inducible resistance determination. In total, 21 out of 28 RGM and 9 of 12 SGM reference strains have the MICs of fidaxomicin at or below 1 µg ml. Fidaxomicin also showed low MIC values for some clinical isolates including complex, complex, , and . Fidaxomicin also has no inducible macrolide resistance in complex in comparison with clarithromycin. Fidaxomicin has high activity against most of the NTM reference strains and some prevalent NTM clinical isolates. This promising finding warrants further investigation on the actions of fidaxomicn and as a potential antibiotic for NTM treatment.
非结核分枝杆菌（NTM）感染在全球范围内呈上升趋势，并且对许多治疗结核病的一线和二线药物具有相对抗性。大环内酯类抗生素，如克拉霉素和阿奇霉素，是治疗 NTM 感染的关键药物。非达霉素是一种广泛用于治疗感染的大环内酯类抗生素，对尤其是耐多药结核分枝杆菌（MDR-TB）具有高活性，并且与利福平无交叉耐药性。非达霉素可能对 NTM 菌株具有活性。为了确定大环内酯类抗生素非达霉素是否对 NTM 菌株具有活性，本研究首先在参考菌株上测试了非达霉素，结果表明其有效且可行。然后，通过微量肉汤 AlamarBlue 测定法（MABA）方法测试了 28 株快速生长分枝杆菌（RGM）、12 株缓慢生长分枝杆菌（SGM）参考菌株和 103 株 NTM 临床分离株的 MIC。测试了非达霉素、利福平克拉霉素对复合亚种 14 、 5 株诱导耐药性的菌株。总的来说，28 株 RGM 中有 21 株和 12 株 SGM 参考菌株中有 9 株的非达霉素 MIC 值为 1µg/ml 或以下。非达霉素对一些临床分离株也表现出较低的 MIC 值，包括复合亚种、复合亚种、、和。与克拉霉素相比，非达霉素在复合亚种中也没有诱导性大环内酯类耐药性。非达霉素对大多数 NTM 参考菌株和一些常见的 NTM 临床分离株具有高活性。这一有希望的发现值得进一步研究非达霉素的作用，并作为治疗 NTM 的潜在抗生素。
