Model of Chung-Esaki et al for Endocarditis in a Febrile Injection Drug User

 

Patient selection: injection drug user > 17 years old with fever >= 38°C

 

Parameters:

(1) tachycardia (heart rate > 100 bpm at any time during the first 6 hours in the ED)

(2) cardiac murmur

(3) skin infection (abscess or cellulitis)

Parameter	Finding	Points
tachycardia	absent	0
	present	1
cardiac murmur	absent	0
	present	1
skin infection	absent	0
	present	1

 

X =

= (0.63 * (points for tachycardia)) + (0.61 * (points for murmur)) – (points for skin infection)) – 2.61

 

probability of endocarditis =

= 1 / (1 + EXP((-1) * X))

 

Alternatively a point score was developed

 

score =

= (points for tachycardia) + (points for cardiac murmur) – (points for skin infection

 

Interpretation:

• minimum score: -1

• maximum score: 2

• The higher the score the greater the risk of endocarditis.

 

Score	Endocarditis Risk
-1	3%
0	5-7%
1	9-10%
2	20%