Dataset Information

Antimicrobial Susceptibility and Characterization of Resistance Mechanisms of Corynebacteriumurealyticum Clinical Isolates.

ABSTRACT: Corynebacterium urealyticum is a non-diphtherial urease-producing clinically relevant corynebacterial, most frequently involved in urinary tract infections. Most of the C. urealyticum clinical isolates are frequently resistant to several antibiotics. We investigated the susceptibility of 40 C. urealyticum isolated in our institution during the period 2005-2017 to eight compounds representative of the main clinically relevant classes of antimicrobial agents. Antimicrobial susceptibility was determined by the Epsilometer test. Resistance genes were searched by PCR. All strains were susceptible to vancomycin whereas linezolid and rifampicin also showed good activity (MICs90 = 1 and 0.4 mg/L, respectively). Almost all isolates (39/40, 97.5%) were multidrug resistant. The highest resistance rate was observed for ampicillin (100%), followed by erythromycin (95%) and levofloxacin (95%). Ampicillin resistance was associated with the presence of the blaA gene, encoding a class A β-lactamase. The two rifampicin-resistant strains showed point mutations driving amino acid replacements in conserved residues of RNA polymerase subunit β (RpoB). Tetracycline resistance was due to an efflux-mediated mechanism. Thirty-nine PFGE patterns were identified among the 40 C. urealyticum, indicating that they were not clonally related, but producing sporadic infections. These findings raise the need of maintaining surveillance strategies among this multidrug resistant pathogen.

SUBMITTER: Chapartegui-Gonzalez I

PROVIDER: S-EPMC7400432 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Antimicrobial Susceptibility and Characterization of Resistance Mechanisms of Corynebacterium urealyticum Clinical Isolates.

Chapartegui-González Itziar I Fernández-Martínez Marta M Rodríguez-Fernández Ana A Rocha Danilo J P DJP Aguiar Eric R G R ERGR Pacheco Luis G C LGC Ramos-Vivas José J Calvo Jorge J Martínez-Martínez Luis L Navas Jesús J

Antibiotics (Basel, Switzerland) 20200713 7

Corynebacterium urealyticum is a non-diphtherial urease-producing clinically relevant corynebacterial, most frequently involved in urinary tract infections. Most of the C. urealyticum clinical isolates are frequently resistant to several antibiotics. We investigated the susceptibility of 40 C. urealyticum isolated in our institution during the period 2005-2017 to eight compounds representative of the main clinically relevant classes of antimicrobial agents. Antimicrobial sus ...[more]

PMID: 32668585

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Dataset Information

Antimicrobial Susceptibility and Characterization of Resistance Mechanisms of Corynebacteriumurealyticum Clinical Isolates.

Publications

Antimicrobial Susceptibility and Characterization of Resistance Mechanisms of <i>Corynebacterium</i> <i>urealyticum</i> Clinical Isolates.

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