Impact of adherence to surgical and non-surgical components of infective endocarditis guidelines and recommendations

Clinical characteristics and analysis of prognostic factors in methicillin-resistant Staphylococcus aureus endocarditis: A retrospective multicenter study in Japan

BACKGROUND

Infective endocarditis (IE) caused by MRSA (methicillin-resistant Staphylococcus aureus) is associated with a high mortality rate. This study aimed to elucidate the characteristics of patients with MRSA-IE in Japan and identify the factors associated with prognosis.

METHODS

This retrospective study included patients with a confirmed diagnosis of IE caused by MRSA, between January 2015 and April 2019.

RESULTS

A total of 65 patients from 19 centers were included, with a mean age of 67 years and 26 % were female. Fifty percent of the patients with IE were had nosocomial infections and 25 % had prosthetic valve involvement. The most common comorbidities were hemodialysis (20 %) and diabetes (20 %). Congestive heart failure was present in 86 % of patients (NYHA class I, II: 48 %; III, IV: 38 %). The 30-day and in-hospital mortality rates were 29 % and 46 %, respectively. Multi-organ failure was the primary cause of death, accounting for 43 % of all causes of death. Prognostic factors for in-hospital mortality were age, disseminated intravascular coagulation, daptomycin and/or linezolid as initial antibiotic therapy, and surgery. Surgical treatment was associated with a lower mortality rate (odds ratio [OR], 0.026; 95 % confidence interval [CI], 0.002-0.382; p = 0.008 for 30-day mortality and OR, 0.130; 95 % CI; 0.029-0.584; p = 0.008 for in-hospital mortality).

CONCLUSION

Mortality due to MRSA-IE remains high. Surgical treatment is a significant prognostic predictor of MRSA-IE.

Infective endocarditis outcomes at a tertiary hospital in Western Australia: a retrospective cohort study from 2016 to 2021

BACKGROUND

Infective endocarditis (IE) is a severe infection with considerable mortality. It is associated with geographical variation, complicating diagnosis and treatment of patients in a standardised manner.

AIM

To evaluate the characteristics and management outcomes of patients with IE in Royal Perth Hospital (RPH).

METHODS

A single-centre, retrospective cohort study. Data were collected from medical records of 131 patients with a diagnosis of IE admitted to RPH between 2016 and 2021.

RESULTS

Eighty-four patients with definite IE were included for analysis. The median age of patients was 51.5 years and 77.4% were male. Compared to the general Australian population, there was disproportionately greater representation of Indigenous Australians (21.4%), those with a history of injecting drug use (IDU) (27.4%), rheumatic heart disease (14.3%) and previous IE (13.1%). The most commonly affected valve was the mitral valve in 46.4% of patients, and the most common pathogen was Staphylococcus aureus in 47.6% of patients. Twelve-month mortality was 16.7%, with significantly increased mortality in those treated non-surgically (25.6% vs 7.3%, P = 0.025). Factors associated with undergoing surgery included the presence of aortic valve disease, perivalvular extension of infection and infection with Enterococcus faecalis, whereas IDU, tricuspid valve disease and S. aureus infection were associated with non-surgical management. Adherence to multidisciplinary team review was 75.0%, and surgical management was performed in 70.7% of patients meeting an indication for surgery.

CONCLUSION

IE mortality rates remain high, particularly in patients who do not undergo surgical management. Streamlined MDT assessment and referral for surgical management where appropriate is necessary to improve outcomes.

A clinical and in vitro assessment of outpatient parenteral benzylpenicillin and ceftriaxone combination therapy for enterococcal endovascular infections

Background

Amoxicillin plus ceftriaxone combination therapy is now standard of care for enterococcal endocarditis. Due to amoxicillin instability in infusion devices, benzylpenicillin plus ceftriaxone may be substituted to facilitate outpatient parenteral antimicrobial therapy (OPAT) delivery, despite lack of guideline endorsement.

Objectives

To assess the clinical efficacy of benzylpenicillin plus ceftriaxone for the management of enterococcal endovascular infections, in addition to assessing this combination’s in vitro synergy.

Patients and methods

Retrospective cohort study assessing unplanned readmissions, relapses and mortality for 20 patients with endovascular Enterococcus faecalis infections treated with benzylpenicillin plus ceftriaxone delivered via OPAT. For a subset of isolates, synergism for both amoxicillin and benzylpenicillin in combination with ceftriaxone was calculated using a chequerboard method.

Results

Patients had endovascular infections of native cardiac valves (n = 11), mechanical or bioprosthetic cardiac valves (n = 7), pacemaker leads (n = 1) or left ventricular assistant devices (n = 1). The median duration of OPAT was 22 days, and the most frequent antimicrobial regimen was benzylpenicillin 14 g/day via continuous infusion and ceftriaxone 4 g once daily via short infusion. Rates of unplanned readmissions were high (30%), although rates of relapsed bacteraemia (5%) and 1 year mortality (15%) were comparable to the published literature. Benzylpenicillin less frequently displayed a synergistic interaction with ceftriaxone when compared with amoxicillin (3 versus 4 out of 6 isolates).

Conclusions

Lower rates of synergistic antimicrobial interaction and a significant proportion of unplanned readmissions suggest clinicians should exercise caution when treating enterococcal endovascular infection utilizing a combination of benzylpenicillin and ceftriaxone via OPAT.