|
Overview :
The presence of certain clinical findings can help predict
bacteremia or fungemia in critical care patients with the Sepsis Syndrome. Since
most patients with the Sepsis Syndrome do not have bloodstream infections, this
can help separate patients according to their risk for bloodstream
infection.
NOTE: The Sepsis Syndrome is described in the chapter on
Critical Care.
Method:
• The
variables associated with disease state are identified by logistic regression
analysis.
• Points
are assigned by dividing the beta coefficient by an appropriate denominator to
yield an integer score.
• Since a
model for Gram-positive bacteremia did not perform well, the model for
Staphylococcus aureus was developed.
Any Bacteremia
|
Variable |
beta
coefficient |
Odds Ratio |
Points |
|
intercept |
-2.03 |
|
|
|
suspected or documented focal infection at onset |
0.86 |
2.4 |
3 |
|
no antibiotics before onset |
0.84 |
2.4 |
3 |
|
any liver disease |
0.59 |
1.8 |
2 |
|
Hickman catheter present |
0.57 |
1.8 |
2 |
|
altered mental status within 24 hours |
0.61 |
1.8 |
2 |
|
focal abdominal signs within 24 hours |
0.49 |
1.6 |
2 |
where:
• any liver
disease = cirrhosis with or without portal hypertension, chronic hepatitis
within last 6 months, hepatic failure with coma or encephalopathy within last 6
months
risk score for any bacteremia =
= SUM(points for variables present)
Interpretation:
• minimum score: 0
• maximum score: 14
|
Risk Score |
Percent with
Bacteremia |
|
0 |
14.5% |
|
1-2 |
18.5% |
|
3-4 |
20.5% |
|
5-6 |
38% |
|
>= 7 |
60.6% |
Staphylococcus Aureus
Bacteremia
|
Variable |
beta
coefficient |
Odds Ratio |
Points |
|
intercept |
-3.62 |
|
|
|
suspected or documented focal infection with S. aureus
at onset |
1.89 |
6.6 |
2 |
|
hemodialysis before onset |
1.09 |
3.0 |
1 |
|
ventilator use before onset |
0.79 |
2.2 |
1 |
risk score for S. aureus bacteremia =
= SUM(points for variables present)
Interpretation:
• minimum score: 0
• maximum score: 4
|
Risk Score |
Percent with S. aureus
Bacteremia |
|
0 |
2.6% |
|
1 |
4.8% |
|
2 |
18.9% |
|
>= 3 |
21% |
Any Gram-negative Rod
Bacteremia
|
Variable |
beta
coefficient |
Odds Ratio |
Points |
|
intercept |
-3.1 |
|
|
|
total parenteral nutrition before onset |
1.57 |
4.8 |
3 |
|
no antibiotics before onset |
1.30 |
3.7 |
2 |
|
history of Gram-negative bacteremia |
1.15 |
3.2 |
2 |
|
Hickman catheter present |
0.72 |
2.1 |
1 |
|
focal abdominal signs within 24 hours |
0.63 |
1.9 |
1 |
|
chills |
0.51 |
1.7 |
1 |
risk score for Gram-negative bacteremia =
= SUM(points for variables present)
Interpretation:
• minimum score: 0
• maximum score: 10
|
Risk Score |
Percent with Gram-negative
Bacteremia |
|
0 |
5.3% |
|
1 |
6.2% |
|
2 |
12.8% |
|
3 |
20.3% |
|
>= 4 |
41.9% |
Any Fungemia
|
Variable |
beta
coefficient |
Odds ratio |
Points |
|
intercept |
-5.27 |
|
|
|
fungal infection at any site |
2.32 |
10.1 |
5 |
|
bowel perforation |
1.58 |
4.9 |
3 |
|
pyuria |
1.27 |
3.6 |
2 |
|
any liver disease |
1.16 |
3.2 |
2 |
|
Hickman catheter present |
1.10 |
3.0 |
2 |
|
altered mental status within 24 hours |
0.99 |
2.7 |
2 |
risk score for any fungemia =
= SUM(points for variables present)
Interpretation:
• minimum score: 0
• maximum score: 16
|
Risk Score |
Percent with
Fungemia |
|
0 |
0.6% |
|
1-3 |
1.3% |
|
4-6 |
5.1% |
|
>= 7 |
26.1% |
|