Comparison of Staphylococcus Aureus Endocarditis Risk Factors With Bacteremia

Introduction: Infective endocarditis (IE) is endothelial damage of the endocardium, which is caused by infection. The etiologic agents' highest mortality and morbidity rates are associated with staphylococcus aureus (S. aureus). Accordingly, the knowledge of different risk factors for IE caused by the S. aureus is necessary.Material and methods: This study is an observational-analytical retrospective cohort study on 139 patients with staphylococcus aureus bacteremia (SAB), who referred to a cardiac center during 2011-2019. This study aimed to evaluate the risk factors in 48 patients with staphylococcus aureus endocarditis, who were selected from139 patients with S. aureus bacteremia. Results: The mean age (±SD) of the patients is 56.61 (±16.58), and85 (61.2%) persons are male. Forty-eight patients (34.5%) are diagnosed with staphylococcus aureus endocarditis regarding Duke criteria. In this study, the following risk factors were significantly associated with S. aureus endocarditis: age (p=0.003), long-term bacteremia (p=0.041), prosthetic heart valve (p=0.016), pre-existing IE (p=0.048), and embolic events (p=0.039).Conclusion: According to the findings, a significant number of patients with staphylococcus aureus bacteremia (SAB) have IE with different risk factors. Future studies with a larger sample size are recommended to detect IE risk factors.

Moxifloxacin Monotherapy in Left-Sided Staphylococcus aureus Endocarditis

Staphylococcus aureus is the major cause of endocarditis, and its mortality has remained high despite therapeutic procedures over time. A case of left-sided native valve endocarditis caused by methicillin-sensitive Staphylococcus aureus which responded well to moxifloxacin monotherapy is described. An 83-year-old woman with a history of current hospitalization presented with fatigue and fever. Transthoracic echocardiography depicted vegetation, and blood cultures were positive for Staphylococcus aureus. After a 14-day intravenous administration of moxifloxacin, a good clinical response was achieved, and antibiotic regimen transitioned to oral moxifloxacin for an additional four-week therapy.

Evolution of antimicrobial resistance and mortality in Staphylococcus aureus endocarditis during 15 years in a university hospital

Introduction. One of the most aggressive microorganisms in infective endocarditis (IE) is Staphylococcus aureus. We analyse the resistance of S. aureus to antibiotics and its impact on the clinical course of IE in a recent 15-year period. Methods. Retrospective study of patients with IE in a university hospital from 2005 to 2019. Bivariate and multivariate analysis of severity at admission, comorbidities, minimum inhibitory concentrations (MIC) and mortality. Results. Of the 293 IE cases, 66 (22.5%) were due to S. aureus, and 21 (7.2%) were methicillin-resistant S. aureus (MRSA). The prevalence of strains with a MIC to vancomycin ≥ 1mg/L increased from 4.8% to 63.6% (p <0.001) and the cases of MRSA from 38 to 27.3% (p = 0.045). Older age (p= 0.02), comorbidity (p <0.01) and nosohusial origin (p = 0.01), were factors associated with MRSA. But the antimicrobial resistance and severity on admission were not associated with exitus; predictive factors were the right-sided IE (OR = 0.08; 95% CI: 0.01-0.51), comorbidities (OR per Charlson index point = 1.30; 95% CI: 1.01-1.69) and creatinine on admission (OR per mg / dL = 1.56; 95% CI = 1.01- 2.35; p = 0.04). Conclusion. We have experienced an increase in IE cases with MIC to vancomycin ≥ 1mg/L, without significant variation in infections due to MRSA. Antimicrobial resistance was not associated with mortality, but comorbidity and left involvement were predictive factors.