1. Clavulanate combinations with mecillinam, cefixime or cefpodoxime against ESBL-producing Enterobacterales frequently associated with blaOXA-1 in a paediatric population with febrile urinary tract infections.
- Author
-
Birgy, André, Madhi, Fouad, Jung, Camille, Levy, Corinne, Cointe, Aurélie, Bidet, Philippe, Hobson, Claire Amaris, Bechet, Stéphane, Sobral, Elsa, Vuthien, Hoang, Ferroni, Agnès, Aberrane, Saïd, Cuzon, Gaëlle, Beraud, Laetitia, Gajdos, Vincent, Launay, Elise, Pinquier, Didier, Haas, Hervé, Desmarest, Marie, and Dommergues, Marie-Aliette
- Subjects
CHILD patients ,CLAVULANIC acid ,ORAL drug administration ,TREATMENT effectiveness ,URINARY tract infections ,AMOXICILLIN ,CEFTAZIDIME ,RESEARCH ,RESEARCH methodology ,CEFOTAXIME ,MEDICAL cooperation ,EVALUATION research ,PENICILLIN ,COMPARATIVE studies ,ANTIBIOTICS ,PHARMACODYNAMICS - Abstract
Objectives: Oral treatment of febrile urinary tract infections (FUTIs) can be impaired by MDR Enterobacterales often combining ESBL and inhibitor-resistant genes. We studied the impact of β-lactamases and Enterobacterales' genotypes on the cefixime, cefpodoxime and mecillinam ± amoxicillin/clavulanate MICs.Materials and Methods: In this multicentric study, we included 251 previously whole-genome-sequenced ESBL-producing Enterobacterales, isolated in French children with FUTIs. The MICs of cefixime, cefpodoxime, mecillinam alone and combined with amoxicillin/clavulanate were determined and analysed with respect to genomic data. We focused especially on the isolates' ST and their type of β-lactamases. Clinical outcomes of patients who received cefixime + amoxicillin/clavulanate were also analysed.Results: All isolates were cefixime and cefpodoxime resistant. Disparities depending on blaCTX-M variants were observed for cefixime. The addition of amoxicillin/clavulanate restored susceptibility for cefixime and cefpodoxime in 97.2% (MIC50/90 of 0.38/0.75 mg/L) and 55.4% (MIC50/90 of 1/2 mg/L) of isolates, respectively, whatever the ST, the blaCTX-M variants or the association with inhibitor-resistant β-lactamases (34.2%). All isolates were susceptible to mecillinam + amoxicillin/clavulanate with MIC50/90 of 0.19/0.25 mg/L, respectively. Neither therapeutic failure nor any subsequent positive control urine culture were reported for patients who received cefixime + amoxicillin/clavulanate as an oral relay therapy (n = 54).Conclusions: Despite the frequent association of ESBL genes with inhibitor-resistant β-lactamases, the cefixime + amoxicillin/clavulanate MICs remain low. The in vivo efficacy of this combination was satisfying even when first-line treatment was ineffective. Considering the MIC distributions and pharmacokinetic parameters, mecillinam + amoxicillin/clavulanate should also be an alternative to consider when treating FUTIs in children. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF