TABLE 2.

Demographic and clinical parameters of patients with BSI due to Proteus mirabilis strains and differences between ESBL-P-PM and ESBL-N-PM isolates

Demographic and clinical parametersNo. (%) of patientsaP valueb
ESBL-P-PMESBL-N-PM
No. of BSI patients9c14ND
No. of BSI episodes11c14ND
Age (yr) (mean ± SD)70.9 ± 17.567.3 ± 18.2NS
Sex (male/female)7/27/7ND
McCabe and Jackson groupsd
    Nonfatal5 (55.6)8 (57.1)NS
    Ultimately fatal3 (33.3)4 (28.6)NS
    Rapidly fatal1 (11.1)2 (14.3)NS
Charlson weighted index (mean ± SD)e4.0 ± 2.54.1 ± 2.6NS
Severity of septicemia
    Sepsis6 (66.7)11 (78.6)NS
    Severe sepsis2 (22.2)2 (14.3)NS
    Septic shock1 (11.1)1 (7.1)NS
Previous hospitalizations (during the last 12 months)6 (66.7)8 (57.1)NS
Previous hospitalization in nursing home5 (55.6)3 (21.4)0.04
Hospital-acquired BSI3 (33.3)6 (42.9)NS
Hospital stay before BSI diagnosis (days) (mean ± SD)16.8 ± 30.36.0 ± 6.90.10
Length of hospital stay (days) (mean ± SD)86.2 ± 193.419.4 ± 8.00.10
Empirical treatment
    Provided9 (100.0)12 (85.7)NS
    Adequate5 (55.6)12 (85.7)0.04
Adequate treatment after ID/AST results4 (44.4)12 (85.7)0.04
Predisposing factors
    Bladder catheter9 (100.0)8 (57.1)0.01
    Previous use of antibiotics4 (44.4)3 (21.4)0.09
    Intravascular catheter4 (44.4)3 (21.4)0.09
    Corticosteroids or antineoplastic therapy2 (22.2)4 (28.6)NS
    Previous surgery0 (0.0)3 (21.4)NS
    Drainages0 (0.0)3 (21.4)NS
    Intubation1 (11.1)1 (7.1)NS
Secondary BSI
    All patients4 (44.4)3 (21.4)0.09
    Urinary tract4 (44.4)f3 (21.4)g0.09
    Other0 (0.0)0 (0.0)NS
Overall mortality3 (33.3)2 (14.3)NS
Mortality attributable to BSI3 (33.3)0 (0.0)0.04
  • a Data are number (%) of patients, unless otherwise indicated.

  • b NS, not significant; ND, not determined.

  • c One patient had three different BSI; therefore, statistical analysis was performed considering only 9 BSI patients.

  • d McCabe and Jackson groups used to classify the severity of the underlying disease (22).

  • e Comorbidity scores determined according to the Charlson weighted index (6).

  • f Three from bladder catheter.

  • g One from bladder catheter.