Patient selection: infant <= 60 days old in the Emergency Department with history of fever at home
Exclusions: ill-appearing or with complex chronic conditions
Outcome: invasive bacterial infection (bacteremia and/or bacterial meningitis)
Parameters:
(1) age in days
(2) highest temperature recorded in the Emergency Department in °C
(3) absolute neutrophil count per µL
(4) urinalysis
|
Parameter
|
Finding
|
Points
|
|
age in days
|
< 21 days
|
1
|
|
|
21 to 60 days
|
0
|
|
highest temperature
|
< 38.0°C
|
0
|
|
|
38.0 to 38.4°C
|
2
|
|
|
>= 38.5 °C
|
4
|
|
absolute neutrophil count
|
< 5,185 per µL
|
0
|
|
|
>= 5,185 per µL
|
2
|
|
urinalysis
|
normal
|
0
|
|
|
abnormal
|
3
|
total score =
= SUM(points for all 4 parameters)
Interpretation:
• minimum score: 0
• maximum score: 10
• A score >= 2 was seen in all infants with meningitis.
|
Score
|
Risk IBI
|
|
0 or 1
|
low
|
|
2 or 3
|
moderate
|
|
4 to 10
|
high
|
Expressed as a clinical decision rule, an infant is at low risk of IBI if all of the following are true:
(1) temperature in ED < 38.0°C (fever by history only)
(2) absolute neutrophil count < 5,185 per µL
(3) normal urinalysis
(4) not ill-appearing
Performance:
• The area under the ROC curve is 0.83.
