Resistance to quinolones, cephalosporins and macrolides in Escherichia coli causing bacteraemia in Peruvian children. (December 2017)

• Record Type: Journal Article
• Authors: Palma, Noemí; Pons, Maria J.; Gomes, Cláudia; Mateu, Judit; Riveros, Maribel; García, Wilfredo; Jacobs, Jan; García, Coralith; Ochoa, Theresa J.; Ruiz, Joaquim
• Is Part Of: Journal of global antimicrobial resistance. Volume 11(2017)
• Page Start: 28
• Page End: 33
• Publication Date: 2017-12
• Subjects: Bacteraemia -- Antimicrobial resistance -- Extended-spectrum β-lactamase (ESBL) -- Quinolone resistance -- Macrolide resistance -- Peru; Drug resistance -- Periodicals; Drug resistance -- Periodicals; Drug resistance; Periodicals; 616.9041
• DOI: 10.1016/j.jgar.2017.06.011
• Languages: English
• ISSNs: 2213-7165

Abstract

Highlights: Escherichia coli from bacteraemia in Peruvian children have high levels of antimicrobial resistance. Widespread of bla CTX-M-15 and first description of bla CTX-M-65 in Peru. Relevant role of efflux pump overexpression in azithromycin resistance. Low number of transferable mechanisms of quinolone resistance among bacteraemic E. coli . Mph(A) was the most frequent transferable mechanisms of macrolide resistance. Abstract: Objectives: To characterise the β-lactam, quinolone and macrolide resistance levels and mechanisms in 62 Escherichia coli isolates causing bacteraemia in Peruvian children. Methods: Minimum inhibitory concentrations (MICs) of ciprofloxacin, nalidixic acid (NAL) and azithromycin were determined in the presence and absence of Phe-Arg-β-naphthylamide. Susceptibility to other 14 antimicrobial agents was also established. Extended-spectrum β-lactamases (ESBLs) were identified, and mutations in gyrA and parC as well as the presence of transferable mechanisms of quinolone resistance (TMQR) and macrolide resistance (TMMR) were determined. Results: Fifty isolates (80.6%) were multidrug-resistant. High proportions of resistance to ampicillin (93.5%), NAL (66.1%) and trimethoprim/sulfamethoxazole (66.1%) were observed. No isolate showed resistance to carbapenems and only two isolates were resistant to nitrofurantoin. Twenty-seven isolates carried ESBL-encoding genes: 2 bla SHV-12 ; 13 bla CTX-M-15 ; 4 bla CTX-M-2 ; 6 bla CTX-M-65 ; and 2 non-identified ESBLs. Additionally, 27 bla TEM-1 and 9 bla OXA-1-like genes were detected. All quinolone-resistant isolates showed target mutations, whilst TMQR were present in four isolates. Efflux pumps played a role in constitutive NAL resistance. The association between quinolone resistance and ESBL production was significant ( P = 0.0011). The mph (A) gene was the most frequent TMMR (16 isolates); msr (A) and erm (B) genes were also detected. Only one TMMR-carrying isolate [presenting mph (A) and erm (B) concomitantly] remained resistant to azithromycin when efflux pumps were inhibited. Conclusions: A variety of ESBL-encoding genes and widespread of bla CTX-M-15 in Lima has been shown. The role of efflux pumps in azithromycin resistance needs to be further evaluated, as well as effective control of the use of antimicrobial agents.