Key points are not available for this paper at this time.
complex (MTBC) strains for implementation in a routine DST workflow. The assay was developed based on the EUCAST (European Committee on Antimicrobial Susceptibility Testing) reference protocol for determination of the minimum inhibitory concentration (MIC) of 14 anti-tuberculous drugs (isoniazid INH, rifampicin RIF, ethambutol EMB, amikacin AMI, moxifloxacin MFX, levofloxacin LFX, bedaquiline BDQ, clofazimine CFZ, delamanid DLM, pretomanid PA, para-aminosalicylic acid PAS, linezolid LZD, ethionamide ETH, and cycloserine CS). Forty MTBC strains with various drug resistance profiles were tested to determine the agreement between MIC results and genotypic drug susceptibility testing (gDST) results derived from whole-genome sequencing (WGS). The agreement between the BMD and gDST results was solid for the majority of the drugs (average agreement 98%, range 90%-100%), including key drugs such as INH, RIF, MFX, LFX, BDQ, DLM, and PA. Ten discrepancies were identified (corresponding to 1.8% of the total number of MIC determinations) and most (8/10) were characterized by MICs equal or close to the potential critical concentration (pCC) applied in the BMD assay. Importantly, the assay can be adjusted to new drug recommendations and concentrations, tailored to local needs. We conclude that the BMD assay provides reliable results, and its implementation in our MTBC routine workflow will produce valuable data that improve our understanding and management of MTBC drug resistance.
Mansjö et al. (Wed,) studied this question.