IJAA Editor's Choice

The Editor in Chief of the International Journal of Antimicrobial Chemotherapy, Prof. Jean-Marc Rolain and his Scientific Assistant, Sophie Baron, have selected the following articles for the Editor's Choice section. 

You can read them both for free for a limited time!

1. Comparisons of whole genome sequencing and phenotypic drug susceptibility testing for Mycobacterium tuberculosis causing MDR-TB and XDR-TB in Thailand by Faksri et al.

Editor's comment:
Increasing the speed of tuberculosis (TB) diagnosis is a current challenge. The assessment of sensitivity to anti-TB drugs is a key diagnostic step that will change the management of the infection. Drug susceptibility tests are still using methods that are time-consuming and difficult to interpret such as the proportional method. The use of whole genome sequencing (WGS) is an interesting alternative for the detection of mutations conferring resistance to anti-TB drugs. In this study, Faksri et al. evaluated the performance of anti-TB drug resistance databases (TB-profiler and PhyResSE) on multidrug resistant (MDR-TB) and extremely drug resistant (XDR-TB) genomes compared to the proportional method. Out of 266 M. tuberculosis genomes analysed, they showed that TB-profiler had an overall concordance rate higher than PhyResSE. Both bases were relatively effective in detecting resistance to first-line anti-TB drugs but lacked sensitivity for the detection of second-line anti-TB drugs (fluoroquinolones or ethionamide). This study shows the potential of WGS for performing anti-TB drug susceptibility tests. However, this method depends on the completeness of the databases used. The use of a single database for detection of resistance is currently insufficient to detect all resistances, especially when the strains are MDR-TB or XDR-TB. In these cases, phenotypic tests seem still recommended.

2. Pandemic spread of blaKPC-2 among Klebsiella pneumoniae ST11 in China is associated with horizontal transfer mediated by IncFII-like plasmids by Fu et al.

Editor's comment:
KPC-producing Klebsiella pneumoniae (KPC-Kp) have been frequently associated to the Clonal complex CC258. This clone is frequently associated with multidrug resistance. Among this clonal complex, the ST11 is the predominant ST type in China. In this study, Fu et al. focused on the link between the ST11 isolates, the presence of blaKPC gene and the transferable IncFII plasmids to better understand the spread of this KPC-Kp in China. First, they show that even if the isolates mainly belong to the ST11, 14 different PFGE type have been detected in this study indicating the presence of several sub-lineages. Moreover, the ST11 isolates were more often associated with the presence of the blaKPC gene than with its absence. The blaKPC-2 gene was mostly surrounded by five different Tn1721 elements on IncFII-like plasmids, suggesting this family of transposon is well adapted to the transmission of the carbapenemase gene. Finally, authors found a strong association between IncFII-like plasmid, blaKPC-2 and Tn1721 transposon, suggesting the IncFII-like plasmid is an adequate vector for the transmission of the Tn1721-blaKPC among K. pneumoniae ST11. These finding represent a first step to understand how some clones have more ability to carry antibiotic resistance within the same species and to identify factors that allow these clones to spread more easily than others.