Distribution of genes encoding 16S rRNA methyltransferase in plazomicin-nonsusceptible carbapenemase-producing Enterobacterales in Brazil

• Published in: Diagnostic microbiology and infectious disease Vol. 99; no. 2; p. 115239
• Main Authors: Bail, Larissa, Ito, Carmen Antonia Sanches, Arend, Lavinia Nery Villa Stangler, Pilonetto, Marcelo, Nogueira, Keite da Silva, Tuon, Felipe Francisco
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.02.2021
• Subjects: Amikacin; Aminoglycosides; Carbapenemase; Enterobacterales; Gentamicin; Carbapenemase; Aminoglycosides; Enterobacterales; Amikacin; Gentamicin
• ISSN: 0732-8893; 1879-0070
• DOI: 10.1016/j.diagmicrobio.2020.115239

•The presence of 16S rRNA methyltranferases in carbapenemase-producing Enterobacterales (CPE) is important to understand the mechanism of resistance in this area and possible dissemination in the country and world.•From 499 CPE, 67 nonclonal and nonsusceptible plazomicin isolates, and 54 encoded 16S-RMTase genes (41 rmtB1, 7 armA, 3 rmtD2, 1 rmtD1 and 2 rmtC). Among 41 samples rmtB1 positive, 40 co-harbored blaKPC-2 and 1 blaOXA-48 gene.•The co-existence of 16S-RMTase and CPE is worrisome because of limited treatment options and the endemic characteristic of KPC and NDM. Despite low rates of susceptibility to amikacin and gentamicin, plazomicin could be an important therapeutic option for CPE. Background: The presence of 16S rRNA methyltranferases (16S-RMTases) in carbapenemase-producing Enterobacterales (CPE) is a major concern because it inactivates all clinical use of aminoglycosides, including plazomicin. The aim of this study is to investigate the prevalence of 16S-RMTases in CPE nonsusceptible to plazomicin collected in different Brazilian hospitals. Methods: All isolates with plazomicin MIC ≥ 4 µg/mL (n = 67) were screened for the presence of 16S-RMTases by sequencing. Results: 54 (80.6%) isolates encoded 16S-RMTase genes (41 rmtB1, 7 armA, 3 rmtD2, 1 rmtD1 and 2 rmtC). Among 41 samples rmtB1 positive, 40 co-harbored blaKPC-2 and 1 blaOXA-48 gene. Of the seven isolates harboring armA gene, 6 were New Delhi Metallo-beta-lactamase (NDM)-producer. rmtD was only found in isolates Klebsiella pneumoniae Carbapenemase (KPC)-producers, one in Serratia marcescens with rmtD2, not reported in Brazil. Conclusion: The co-existence of 16S-RMTase and CPE is worrisome because of limited treatment options and the endemic characteristic of (KPC) and NDM in Brazil.