Table 3.
Univariate analysis of risk factors for isolation of MDR and non-MDR strains of P. mirabilisc
| Characteristic | No. (%) of patients |
Univariate analysis |
|||||
|---|---|---|---|---|---|---|---|
| Controls (n = 100) | Cases |
MDR P. mirabilis vs controls |
Non-MDR P. mirabilis vs controls |
||||
| MDR P. mirabilis (n = 36) | Non-MDR P. mirabilis (n = 63) | OR (95% CI) | P | OR (95% CI) | P | ||
| Demographics | |||||||
| Male sex | 52 (52) | 25 (69.4) | 37 (58.7) | 2.09 (0.87–5.23) | 0.07 | 1.31 (0.66–2.61) | 0.40 |
| Age >65 years | 30 (30) | 14 (38.9) | 40 (63.5) | 1.48 (0.61–3.51) | 0.32 | 4.05 (1.97–8.37) | <0.001 |
| Baseline clinical characteristics | |||||||
| Solid tumor | 32 (32) | 14 (38.9) | 17 (26.9) | 1.35 (0.56–3.18) | 0.45 | 0.78 (0.36–1.65) | 0.49 |
| Hematological malignancy | 3 (3) | 4 (11.1) | 6 (9.5) | 4.04 (0.63–28.71) | 0.06 | 3.40 (0.68–21.66) | 0.07 |
| Liver disease | 5 (5) | 6 (16.6) | 8 (12.7) | 3.80 (0.88–16.75) | 0.02 | 2.76 (0.74–11.21) | 0.07 |
| Diabetes | 18 (18) | 10 (27.8) | 14 (22.2) | 1.75 (0.63–4.59) | 0.21 | 1.30 (0.54–3.04) | 0.50 |
| Chronic renal failure | 16 (16) | 15 (41.7) | 10 (15.9) | 3.75 (1.45–9.52) | 0.001 | 0.99 (0.37–2.52) | 0.98 |
| Charlson index ≥3 | 41 (41) | 17 (47.2) | 32 (50.8) | 1.28 (0.55–2.96) | 0.51 | 1.48 (0.74–2.94) | 0.22 |
| History (prior to index admission) | |||||||
| Admission from LTCF | 3 (3) | 8 (22.2) | 2 (3.2) | 9.23 (2.01–56.44) | <0.001 | 1.06 (0.08–9.52) | 0.94 |
| Previous hospitalization | 45 (45) | 24 (66.7) | 33 (52.4) | 2.44 (1.03–5.96) | 0.02 | 1.34 (0.68–2.65) | 0.35 |
| Hospital stay (days) before BSI onset (median [range])a | 19 (6–44) | 15 (2–89) | 8 (2–140) | 0.26 | 0.001 | ||
| Previous ICU stay | 15 (15) | 8 (22.2) | 18 (28.6) | 1.61 (0.53–4.58) | 0.32 | 2.26 (0.97–5.30) | 0.03 |
| Immunosuppressive therapy | 11 (11) | 8 (22.2) | 22 (34.9) | 2.31 (0.72–7.00) | 0.09 | 4.34 (1.80–10.80) | <0.001 |
| Radiotherapy | 3 (3) | 5 (13.9) | 1 (1.6) | 5.21 (0.93–34.97) | 0.02 | 0.52 (0.01–6.68) | 0.57 |
| Surgery | 44 (44) | 20 (55.6) | 26 (41.3) | 1.59 (0.68–3.69) | 0.23 | 0.89 (0.44–1.77) | 0.73 |
| Total parenteral nutrition | 22 (22) | 16 (44.4) | 7 (11.1) | 2.83 (1.15–6.85) | 0.01 | 0.44 (0.14–1.17) | 0.07 |
| Invasive procedures | 45 (45) | 30 (83.3) | 43 (68.2) | 6.11 (2.21–19.33) | <0.001 | 2.62 (1.29–5.39) | 0.003 |
| Dialysis | 13 (13) | 9 (25) | 6 (9.5) | 2.23 (0.74–6.34) | 0.09 | 0.70 (0.20–2.13) | 0.50 |
| Central venous catheter | 39 (39) | 14 (38.8) | 23 (36.5) | 0.99 (0.41–2.32) | 0.99 | 0.89 (0.44–1.81) | 0.74 |
| Urinary catheter | 30 (30) | 22 (61.1) | 38 (60.3) | 3.66 (1.54–8.80) | 0.001 | 3.54 (1.73–7.25) | <0.001 |
| Others | |||||||
| Previous UTIs (≥2 episodes) | 8 (8) | 9 (25) | 13 (20.6) | 3.83 (1.17–12.51) | 0.008 | 2.99 (1.05–8.86) | 0.01 |
| Previous antimicrobial use | 29 (29) | 24 (66.7) | 29 (46) | 4.89 (2.01–12.14) | <0.001 | 2.08 (1.02–4.24) | 0.02 |
| Oxyimino-cephalosporins | 7 (7) | 9 (25) | 9 (14.3) | 4.42 (1.31–5.22) | 0.004 | 2.21 (0.68–7.39) | 0.12 |
| Fluoroquinolones | 5 (5) | 8 (22.2) | 8 (12.7) | 5.42 (1.41–22.58) | 0.002 | 2.76 (0.74–11.21) | 0.07 |
| Aminoglycosides | 2 (2) | 3 (8.3) | 2 (3.2) | 4.45 (0.48–54.75) | 0.08 | 1.60 (0.11–22.62) | 0.63 |
| β-Lactam–β-lactamase inhibitors | 16 (16) | 9 (25) | 7 (11.1) | 1.75 (0.60–4.77) | 0.23 | 0.65 (0.21–1.82) | 0.38 |
| Othersb | 5 (5) | 4 (11.1) | 6 (9.5) | 2.37 (0.44–11.70) | 0.20 | 2.00 (0.48–8.64) | 0.26 |
a
In cases, the number of days from admission to BSI onset. This variable was evaluated only for BSI detected after ≥48 h hospital admission. In controls, who never developed BSI, the values reflect the length of the entire hospital stay.
b
Other antimicrobials included macrolides, glycopeptides, and aminopenicillins.
c
Data are expressed as numbers (%) unless otherwise stated. Abbreviations: ICU, intensive care unit; LTCF, long-term care facility; BSI, bloodstream infection; UTI, urinary tract infection; MDR, multidrug resistant.