Patient selection:
(1) adult >= 18 years of age
(2) presence of an intravascular catheter
(3) bacteremia with Staphylococcus aureus
(4) (inflammation about catheter insertion site or culture of catheter tip positive) AND no other source evident
(5) exclusions: neutropenia, polymicrobial infection, death before evaluation
Hematogenous complications included one or more of the following occurring within 12 weeks after the initial positive blood culture:
(1) infective endocarditis
(2) septic arthritis
(3) vertebral osteomyelitis secondary to hematogenous spread
Risk factors from multivariate analysis:
(1) duration of symptoms (defined as number of days between onset of symptoms and the day of the initial blood culture positive for Staphylococcus aureus)
(2) hemodialysis dependence
(3) either long term intravascular catheter (tunneled cuffed intravascular catheter or subcutaneous port catheter) OR permanent foreign body (noncatheter prosthesis)
(4) Staphylococcus aureus methicillin-resistant (MRSA)
where:
• Permanent foreign body may include a pacemaker, prosthetic heart valve, orthopedic hardware, or synthetic vascular graft.
• The duration of symptoms refers to the number of days before diagnosis. I assume therefore that it refers to the number of days before the blood culture was called positive, rather than the day it was drawn.
The risk increased for the duration of symptoms for each day of symptoms (odds ratio increased approximately by 1 for each day of duration).
Additional factors affecting risk:
(1) community onset
(2) higher APACHE II score after admission
(3) presence of strain producing the sea exotoxin
(4) failure to remove the infected catheter
