Table 5.
Logistic models to identify factors associated by univariate analysis with coverage of the isolated organism by the antibiotic prescribed (A), treatment with multiple antibiotics (“double coverage”) (B), and discordant anti-mrsa therapy (C)
| Variable | (A) Coverage of the organism isolated Δ (n=156) or (95%C.I.) | (B) Double coverage (n = 804) or (95%C.I.) | (C) Discordant anti-mrsa therapy (n = 181) or (95%C.I.) |
|---|---|---|---|
|
Age group (adult vs. pediatric) |
1.92 (0.78-4.76) |
5.60 (3.39-9.25) |
1.63 (0.82-3.23) |
|
Infection Location |
|
|
|
| Hand |
Ref. |
Ref. |
Ref. |
| Other extremity |
1.71 (0.45-6.44) |
1.37 (0.87-2.18) |
1.16 (0.41-3.25) |
| Buttock |
*** |
1.07 (0.55-2.11) |
1.00 (0.28-3.54) |
| Trunk |
2.31 (0.5-10.67) |
1.00 (0.56-1.78) |
0.64 (0.22-1.87) |
| Head |
0.62 (0.1-3.66) |
1.15 (0.44-2.96) |
4.00 (0.40-39.83) |
| Face |
4.92 (0.49-49.61) |
0.95 (0.54-1.68) |
0.46 (0.13-1.59) |
| Genitalia |
0.31 (0.02-6.11) |
1.07 (0.30-3.81) |
0.67 (0.04-12.27) |
| Multiple Locations |
1.23 (0.11-14.42) |
1.07 (0.45-2.54) |
0.67 (0.08-5.75) |
|
Previous assessment for this infection |
1.27 (0.4-4.02) |
0.85 (0.60-1.20) |
0.86 (0.42-1.79) |
|
Previous antibiotic treatment for this infection |
4.13 (0.53-32.28) |
0.81 (0.54-1.22) |
0.45 (0.19-1.07) |
|
Disposition (hospital admission) |
2.78 (1.12-6.89)* |
0.99 (0.73-1.35) |
0.66 (0.33-1.32) |
|
I&D performed |
4.47 (1.71-11.65)* |
1.07 (0.77-1.47) |
0.87 (0.47-1.60) |
|
Culture performed |
N/A |
1.37 (1.00-1.87) |
N/A |
|
Gender |
|
|
|
| Male |
Ref. |
Ref. |
Ref. |
| Female |
0.92 (0.38-2.24) |
0.75 (0.56-1.00) |
0.82 (0.45-1.47) |
|
Ethnicity/race |
|
|
|
| White |
Ref. |
Ref. |
Ref. |
| Black |
1.58 (0.49-5.05) |
0.65 (0.43-0.97)* |
0.89 (0.41-1.89) |
| Hispanic/Other |
5.62 (0.71-44.27) |
0.72 (0.48-1.09) |
1.06 (0.46-2.42) |
|
Health insurance status |
|
|
|
| Private |
Ref. |
Ref. |
Ref. |
| Governmental |
1.31 (0.41-4.19) |
0.94 (0.66-1.34) |
0.85 (0.40-1.77) |
| Both private and Governmental |
0.11 (0.02-0.5)* |
0.80 (0.45-1.43) |
1.94 (0.36-10.50) |
| None | 1.63 (0.44-5.98) | 1.23 (0.84-1.81) | 0.69 (0.33-1.47) |
Δ excludes cultures with no growth or mixed flora and patients not treated with antibiotics.
* denotes statistically significant result.
*** variable had perfect prediction in the model.
NB: Three univariable logistic models were created to identify demographic or clinical variables associated with (A) coverage of the organism isolated by the empiric ED antibiotic therapy, (B) use of multiple antibiotics as empiric therapy (“double coverage”), and (C) discordance between use of anti-MRSA antibiotics and presence of MRSA as identified by microbiologic culture. In the third regression model, concordance was defined as presence of MRSA in culture when any anti-MRSA treatment was prescribed or presence of MSSA in culture when only anti-MSSA treatment was prescribed.