Staph Endocarditis, METs, COPD CPGs & More
A review of staphylococcal Endocarditis
VG Fowler Jr, Miro JM, Hoen B, et al for the ICE Investigators. Staphylococcus aureus endocarditis: a consequence of medical progress. JAMA. 2005;June 22;293(24):3061-3062.
Agroup of infectious diseases experts from centers throughout the world formed the International Collaboration on Endocarditis (ICE) in 1999 to gain a global understanding of infective endocarditis. Using the Duke Criteria patients with definite infective endocarditis in a prospective manner, 275 variables were reported with these cases to a central database maintained at Duke University. The ICE-Prospective Cohort Study (ICE-PCS) enrolled 1,779 patients with infective endocarditis in 39 centers in 16 countries between June 15, 2000, and December 31, 2003, and has been described in a recent report. (Cabell CH, Abrutyn E. Infect Dis Clin North Am. 2002;16:255-72). Staphylococcus aureus was the most common cause of infective endocarditis in this group of patients (n=558; 31.6%); the authors characterized risk factors and clinical issues associated with these cases in this report.
By univariate analysis, compared with non-Staphylococcus aureus infective endocarditis, patients with infective endocarditis due to Staphylococcus aureus were more likely than patients with infective endocarditis due to other pathogens to be female (P<0.001), hemodialysis dependent (P<0.001), have diabetes mellitus (P=0.009), have other chronic illnesses (P<0.001), have a healthcare association (P<0.001), have higher rates of stroke (P<0.001), have systemic embolization (P<0.001), have persistent bacteremia (P<0.001), or die (P<0.001).
Although healthcare associated Staphylococcus aureus infective endocarditis was the most common form of Staphylococcus aureus infective endocarditis, more than 60% of healthcare-associated patients acquired the infection outside the hospital. This reflects the global trend in healthcare delivery patterns favoring ambulatory treatment (e.g., outpatient medication infusion via long-term IV access, hemodialysis)
Multivariate analysis, clinical features independently associated with Staphylococcus aureus infective endocarditis (versus non-Staphylococcus aureus infective endocarditis) were: IV drug use (OR, 9.3; 95% CI, 6.3-13.7); first clinical presentation less than one month after first symptoms (OR, 5.1; 95% CI, 3.2-8.2); healthcare-associated infection (OR, 2.9; 95% CI, 2.1-3.8), persistent bacteremia (OR, 2.3; 95% CI, 1.5-3.8), presence of a presumed intravascular device source (OR, 1.7; 95% CI, 1.2-2.6), stroke (OR, 1.6; 95% CI, 1.2-2.3), or diabetes mellitus (OR, 1.3; 95% CI, 1.1-1.8).
Patients from the United States with Staphylococcus aureus infective endocarditis were more likely to be hemodialysis-dependent, to be diabetic, to have a hemodialysis fistula or a chronic indwelling central catheter as a presumed source of infection, and to have a non-nosocomial healthcare association. Patients from the United States and Brazil were more likely to have Methicillin-resistant Staphyloccocus aureus (MRSA) than were patients from Europe, the Middle East, Australia, or New Zealand. In-hospital mortality rates were similar across regions, although American patients were significantly more likely to develop persistent bacteremia (25.6%, P<0.001).
Characteristics independently associated with mortality among patients with nonintravenous drug-use-associated Staphylococcus aureus infective endocarditis by multivariate analysis included stroke (OR, 3.67; 95% CI, 1.94-6.94), persistent bacteremia (OR, 3.06; 95% CI, 1.75-5.35), diagnosis in Southern Europe or the Middle East (OR, 3.21; 95% CI, 1.17-10.56).
This study establishes Staphylococcus aureus infective endocarditis as the leading cause of infective endocarditis in many regions of the world and spotlights the global emergence of healthcare contact as a risk factor for Staphylococcus aureus infective endocarditis. In a significant portion of these patients, an IV device was the presumed source of bacteremia; prosthetic cardiac devices (pacemakers, defibrillators, or prosthetic cardiac valves) were present in almost one-quarter of the patients.
MRSA was a significant cause of Staphylococcus aureus infective endocarditis and displayed regional variation, accounting for almost 40% of the infective endocarditis caused by Staphylococcus aureus in some regions. Patients with infective endocarditis caused by MRSA were significantly more likely to have pre-existing chronic conditions and healthcare associated infective endocarditis by both univariate and multivariate analysis. They also were often associated with persistent bacteremia. On the other hand, 20% of patients with MRSA infective endocarditis developed their infection in the absence of identifiable healthcare contact.
