RESUMO
Urinary tract infections (UTIs) due to extended-spectrum-ß-lactamase (ESBL)-producing Enterobacteriaceae in children are becoming more frequent, and they are commonly treated initially with a second- or third-generation cephalosporin. We developed a murine model of ascending UTI caused by ESBL-producing Escherichia coli. Using this model, we investigated the renal bacterial burden, interleukin-6 (IL-6) expression, and histopathological alterations caused by ESBL- and non-ESBL-producing bacteria after 1, 2, or 6 days with or without ceftriaxone therapy. The renal bacterial burden, IL-6 concentration, and histological inflammatory lesions were not significantly different between mice infected with ESBL- and non-ESBL-producing bacteria without treatment at any of the time points examined. Following ceftriaxone administration, the bacterial burden was eliminated in the kidneys of mice infected with ESBL- and non-ESBL-producing bacteria on the 6th postinfection day. The histological analysis demonstrated that among mice treated with ceftriaxone, those infected with ESBL-producing bacteria had more profound renal alterations than those infected with non-ESBL-producing bacteria on the 6th day (P < 0.001). In comparison, microbiological outcomes did not differ significantly between mice infected with ESBL- and non-ESBL-producing bacteria at any of the time points examined. The effectiveness of ceftriaxone in mice with UTIs due to ESBL-producing E. coli may have therapeutic implications; it is, however, hampered by limited activity on the histopathological lesions, a finding that needs further investigation.
Assuntos
Antibacterianos/farmacologia , Ceftriaxona/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Rim/efeitos dos fármacos , Pielonefrite/tratamento farmacológico , beta-Lactamases/genética , Animais , Carga Bacteriana/efeitos dos fármacos , Modelos Animais de Doenças , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/patologia , Feminino , Expressão Gênica , Interleucina-6/antagonistas & inibidores , Interleucina-6/biossíntese , Rim/microbiologia , Rim/patologia , Camundongos , Camundongos Endogâmicos BALB C , Pielonefrite/microbiologia , Pielonefrite/patologia , Resultado do Tratamento , beta-Lactamases/metabolismoRESUMO
We report two cases of renal abscess due to Pseudomonas aeruginosa in previously healthy children. The first patient was a nine-year old girl with a three-week history of intermittent fever and the second was a three-year old boy with a four-day history of fever. Pseudomonas aeruginosa was isolated from the urine cultures of both children. In both cases ultrasound and CT/MRI scans revealed the formation of a renal abscess. The patients were successfully treated with administration of antipseudomonal drugs for seven and five weeks, respectively. In both children no surgical intervention was required and the follow-up revealed no impact on the overall renal function or arterial pressure.