Proteus mirabilis Bloodstream Infections: Risk Factors and Treatment Outcome Related to the Expression of Extended-Spectrum β-Lactamases

作者：Andrea Endimiani, Francesco Luzzaro, Gioconda Brigante, Mariagrazia Perilli, Gianluigi Lombardi, Gianfranco Amicosante, Gian María Rossolini, Antonio Toniolo · 发表于：Antimicrobial Agents and Chemotherapy · 年份：2005 · DOI：10.1128/aac.49.7.2598-2605.2005 · 被引用次数：146 · 研究领域：Antibiotic Resistance in Bacteria、Bacterial Identification and Susceptibility Testing、Antibiotic Use and Resistance

Bloodstream infection (BSI) due to Proteus mirabilis strains is a relatively uncommon clinical entity, and its significance has received little attention. This study was initiated to evaluate risk factors and treatment outcome of BSI episodes due to P. mirabilis producing extended-spectrum beta-lactamases (ESBLs). Twenty-five BSI episodes caused by P. mirabilis occurred at our hospital (Ospedale di Circolo e Fondazione Macchi, Varese, Italy) over a 7.5-year period. Phenotypic and molecular methods were used to assess ESBL production. Clinical records of BSI patients were examined retrospectively. Demographic data, underlying diseases (according to McCabe and Jackson classification and Charlson weighted index), risk factors, and treatment outcome were investigated by comparing cases due to ESBL-positive strains to cases due to ESBL-negative strains. Eleven isolates were found to express ESBLs (TEM-52 or TEM-92). The remaining 14 isolates were ESBL negative and were uniformly susceptible to extended-spectrum cephalosporins and monobactams. Comparison of the two groups showed that previous hospitalization in a nursing home (P = 0.04) and use of bladder catheter (P = 0.01) were significant risk factors for infections due to ESBL-positive strains. In addition, cases due to ESBL-positive strains showed a significantly higher mortality attributable to BSI (P = 0.04). BSI cases due to ESBL-negative isolates uniformly responded to therapy, whereas 5/11 cases due to ESBL-positive isola...