Influence of Acetylsalicylic Acid Use on Risk and Outcome of Community-Acquired Staphylococcus aureus Bacteremia: A Population-Based Study

Objective

To investigate the influence of acetylsalicylic acid (ASA) use on risk and outcome of community-acquired Staphylococcus aureus bacteremia (CA-SAB).

Method

We used population-based medical databases to identify all patients diagnosed in northern Denmark with first-time CA-SAB and matched population controls from 2000–2011. Categories for ASA users included current users (new or long-term users), former users, and nonusers. The analyses were adjusted for comorbidities, comedication use, and socioeconomic indicators.

Results

We identified 2638 patients with first-time CA-SAB and 26 379 matched population controls. Compared with nonusers, the adjusted odds ratio (aOR) for CA-SAB was 1.00 (95% confidence interval [CI], 0.88–1.13) for current users, 1.00 (95% CI, 0.86–1.16) for former users, 2.04 (95% CI, 1.42–2.94) for new users, and 0.95 (95% CI, 0.84–1.09) for long-term users. Thirty-day cumulative mortality was 28.0% among current users compared with 21.6% among nonusers, yielding an adjusted hazard rate ratio (aHRR) of 1.02 (95% CI, 0.84–1.25). Compared with nonusers, the aHRR was 1.10 (95% CI, 0.87–1.40) for former users, 0.60 (95% CI, 0.29–1.21) for new users, and 1.06 (95% CI, 0.87–1.31) for long-term users. We observed no difference in the risk or outcome of CA-SAB with increasing ASA dose or by presence of diseases commonly treated with ASA.

Conclusions

Use of ASA did not seem to influence the risk or outcome of CA-SAB. The apparent increased risk among new users may relate to residual confounding from the circumstances underlying ASA treatment initiation. Our finding of no association remained robust with increasing ASA dose and across multiple patient subsets.

1074. Management and Outcomes of Infective Endocarditis Due to Nutritionally Variant Streptococci

Background

Nutritionally variant streptococci (NVS) are an infrequent cause of infective endocarditis (IE) and management recommendations are based on weak levels of evidence largely derived from case reports, small case series, and animal models of experimental endocarditis. Moreover, taxonomic changes have led to some confusion in designation of these organisms.

Methods

We retrospectively collected and analyzed data from 33 patients with NVS IE from 1970 to 2017. Only patients who met modified Duke Criteria for IE were included.

Results

Mean patient age was 55 years and 61% were males. The most common comorbidities included diabetes mellitus (12%), malignancy (3%), heart failure (16%), coronary artery disease (25%), and chronic liver disease (9%). Predisposing valve abnormalities included rheumatic heart disease (11%), bicuspid aortic valve (22%), transplant valvulopathy (3%), mitral valve prolapse (3%), and congenital heart disease (11%). Cultures were reported as NVS (70%), Granulicatella species (18%) and Abiotrophia species (12%). Echocardiogram findings included vegetations (67%), new regurgitation (55%), perivalvular abscess (3%), mitral valve prolapse (3%), and ruptured mitral valve chordae (3%). Both prosthetic (26%) and native valve IE (74%) was seen, and the valves involved were aortic (37%), mitral (50%) and both aortic and mitral (13%). Complications were seen in 27% of patients, including heart failure (17%), splenic infarct (11%), stroke (8%), mycotic aneurysm (3%), and glomerulonephritis (2%). In vitro susceptibility to penicillin, ceftriaxone, and vancomycin was 88%, 80%, and 100%, respectively. The majority (77%) of patients were treated with a combination of β-lactam and aminoglycoside. Median duration of treatment was 33 days. Surgery was performed in 50% of patients with no significant difference in survival between those who were treated with combined medical/surgical treatment and those treated with medical therapy alone. Overall survival at 1, 4, and 10 years was 93%, 83%, and 66%, respectively.

Conclusion

IE due to NVS is a rare entity and is associated with a high rate of serious complications and may involve multiple valves. Long-term, two-thirds of the patients survived more than 10 years.

Disclosures

All authors: No reported disclosures.

Cardiovascular Implantable Electronic Device Infections due to Propionibacterium Species

INTRODUCTION

Propionibacterium species are part of the normal skin flora and often considered contaminants when identified in cultures. However, they can cause life-threatening infections, including prosthetic cardiovascular device infections. Clinical presentation and management of cardiovascular implantable electronic device (CIED) infection due to Propionibacterium species has not been well described.

METHODS

Retrospective review of all cases of CIED infection due to Propionibacterium species admitted to Mayo Clinic between January 1, 1990 and December 31, 2014. Patient charts were reviewed for clinical, microbiological, and imaging data. Descriptive analysis was performed.

RESULTS

We identified 14 patients with CIED infection due to Propionibacterium species, accounting for 2.3% of all CIED infections. Patients were predominantly male (n = 12, 86%). The median age at admission was 58.5 years (range 22-83). Twelve patients had implantable cardioverter defibrillators (ICDs) and two had permanent pacemaker systems. Twelve patients had generator pocket infection (86%). Two patients met clinical criteria for CIED-related infective endocarditis. Median time between last device manipulation and infection was 9 months (range 1-98). All patients were treated with complete device removal and antibiotic therapy. Six-month follow-up data were available for 10 patients (71%), with no relapses documented.

CONCLUSION

CIED infections due to Propionibacterium species accounted for 2.3% of all device infections over a 25-year period. The most common infectious syndrome was generator pocket infection with delayed onset. There was an unanticipated predominance of ICDs in this cohort. Cure was achieved in all cases with complete device removal and antibiotic therapy.

Incidence of infective endocarditis caused by viridans group streptococci before and after publication of the 2007 American Heart Association's endocarditis prevention guidelines

BACKGROUND

The American Heart Association published updated guidelines for infective endocarditis (IE) prevention in 2007 that markedly restricted the use of antibiotic prophylaxis in certain at-risk patients undergoing dental and other invasive procedures. The incidence of IE caused by viridans group streptococci (VGS) in the United States after publication of the 2007 American Heart Association guidelines has not been reported.

METHODS AND RESULTS

We performed a population-based review of all definite or possible cases of VGS-IE using the Rochester Epidemiology Project of Olmsted County, Minnesota. Patient demographics and microbiological data were collected for all VGS-IE cases diagnosed from January 1, 1999, through December 31, 2010. We also examined the Nationwide Inpatient Sample hospital discharge database to determine the number of VGS-IE cases included between 1999 and 2009. We identified 22 cases with VGS-IE in Olmsted County over the 12-year study period. Rates of incidence (per 100 000 person-years) during time intervals of 1999-2002, 2003-2006, and 2007-2010 were 3.19 (95% confidence interval, 1.20-5.17), 2.48 (95% confidence interval, 0.85-4.10), and 0.77 (95% confidence interval, 0.00-1.64), respectively (P=0.061 from Poisson regression). The number of hospital discharges with a VGS-IE diagnosis in the Nationwide Inpatient Sample database during 1999-2002, 2003-2006, and 2007-2009 ranged between 15 318 to 15 938, 16 214 to 17 433, and 14 728 to 15 479, respectively.

CONCLUSIONS

On the basis of data complete through 2010, there has been no perceivable increase in the incidence of VGS-IE in Olmsted County, Minnesota, since the publication of the 2007 American Heart Association endocarditis prevention guidelines.