Capacidad de los laboratorios nacionales de referencia en Latinoamérica para detectar mecanismos de resistencia emergentes

objective: to evaluate the capability of 17 national reference laboratories participating in the latin american quality control program in bacteriology and antibiotic resistance (la-eqas) to detect emerging resistance mechanisms- namely: resistance of enterobacteria to carbapenems due to the presence of klebsiella pneumoniae carbapenemase (kpc) and metallo-beta-lactamase (mbl) type imp, and intermediate resistance of staphylococcus aureus isolates to vancomycin (vancomycin-intermediate resistant s. aureus-visa). methods: the following three isolates were sent to the 17 participating la-eqas laboratories: kpc -producing klebsiella pneumoniae paho-161, imp-producing enterobacter cloacae paho-166, and s. aureus paho-165 with intermediate resistance to vancomycin. performance of each of the following operations was evaluated: interpretation of sensitivity tests, detection of the resistance mechanism, and assessment of either inhibition halo size (disk diffusion method) or minimum inhibitory concentration (mic). results: concordance in the detection of resistance mechanisms was 76.4%, 73.3%, and 66.7% for the k. pneumoniae paho-161, e. cloacae paho-166, and s. aureus paho-165 strains, respectively. concordance between the inhibition areas observed by the participating laboratories and the ranges established by the coordinating laboratory was acceptable for all three isolates, at 90.8%, 92.8%, and 88.9%, respectively. conclusions: overall concordance in on the detection of kpc, mbl, and visa resistance mechanisms was 72.1%. we consider the national reference laboratories in latin america capable of recognizing these emerging resistance mechanisms and expect that maximum levels of concordance will be reached in the future.