Citations

Abstract Background Staphylococcus aureus bacteremia (SAB) is common and is characterized by high rates of morbidity and mortality. The clinical importance of a single positive blood culture bottle (SPBCB), however, is poorly defined despite it being a frequent laboratory finding. We therefore examined patients with SPBCB to determine its clinical significance and to understand the rationale of current practice. Methods We performed a retrospective, multicenter study of patients with a SPBCB for S. aureus in initial cultures from January 2019 to December 2019 using data collected from both electronic health records and the clinical microbiology laboratory. Results Overall, 534 patients with SAB were identified, and 118 (22.1%) had a SPBCB. Among SPBCB cases, 106 (89.3%) were classified as clinically significant while 12 were considered contaminated or of unclear clinical significance. Baseline characteristics were similar between the groups (Table 1). A majority (92.4%) received antibiotic therapy, but patients with clinically significant bacteremia were treated with a longer antibiotic course (25.9 vs 5.7 days, p< 0.001). Outcomes between those with SPBCB (contaminant vs clinically significant) were similar (Table 2). Of note, while there was no difference in use of echocardiography based on PREDICT criteria between the clinically significant SPBCB vs. the multiple positive blood culture bottles (MPBC) cohorts (Table 3), significant differences were seen in both frequency of echocardiography (65.1% vs. 84.6%, P< 0.001) and IE diagnosis (3.8% vs. 14.2%, P=0.002) for patients in the SPBCB vs. MPBC groups, respectively. In addition, those with MPBC had higher 90-day, 6-month and 1-year mortality rates. Conclusion SPBCB was documented in almost one-quarter of SAB cases and should trigger a thorough investigation as its associated mortality was high and complications, including IE, occurred. Although some SPBCB cases may represent contamination, antibiotic treatment of SPBCB was commonplace. Patients with clinically significant SPBCB were less likely to undergo echocardiography and had a reduced prevalence of an IE diagnosis as compared to those with MPBC. Patients with SPBCB may have a more favorable long-term prognosis as compared to that in patients with MPBC. Disclosures Muhammad R. Sohail, MD, Medtronic (Consultant)Philips (Consultant) Larry M. Baddour, MD, Boston Scientific (Individual(s) Involved: Self): Consultant; Botanix Pharmaceuticals (Individual(s) Involved: Self): Consultant; Roivant Sciences (Individual(s) Involved: Self): Consultant

Abstract Background The aim of this study was to determine the incidence, epidemiology, and associated risk factors of bloodstream infection (BSI) in patients who had previously undergone cardiac valve repair. Methods A population-based study that included 7 counties in southeastern Minnesota using the expanded Rochester Epidemiology Project (e-REP) for adults (≥18 years) who underwent valve repair between 1 January 2010 and 31 December 2018 was conducted. Electronic health records were screened for development of BSI and infective endocarditis (IE) from the date of valve repair through 30 July 2020. A 1:4 nested case-control analysis was performed to determine an association, if any, of male sex, Charlson comorbidity index (CCI), and county of residence with BSI. Results A total of 335 patients underwent valve repair, of whom 28 (8.3%) developed an index case of BSI, with 14 episodes occurring within 1 year of surgery. The median age of patients with BSI was 70 years, and 79% were male. The crude incidence of BSI was 1671 cases per 100000 person-years and Escherichia coli was the most common pathogen. Case-control analysis demonstrated a significant correlation between CCI and incidence of BSI (P < .001). Only 4 (14.3%) patients developed IE concurrent with the onset of BSI, and no patients developed IE subsequent to BSI. Conclusions The crude incidence of BSI following valve repair was higher in our e-REP cohort than previous population-based studies, and half of the BSI cases occurred within 1 year of surgery. Patients with a higher CCI at baseline were at increased risk of subsequent BSI.

Aim To provide a contemporary analysis of incidence trends of infective endocarditis (IE) with its changing epidemiology over the past two decades in Europe. Methods A systematic review was conducted at the Mayo Clinic, Rochester. Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus and Web of Science were searched for studies published between 1 January 2000 and 30 November 2020. All studies were independently reviewed by four referees and those that included a population-based incidence of IE in patients, irrespective of age, in Europe were included. Least squares regression was used to estimate pooled temporal trends in IE incidence. Results Of 9138 articles screened, 18 studies were included in the review. Elderly men predominated in all studies. IE incidence increased 4.1% per year (95% CI 1.8% to 6.4%) in the pooled regression analysis of eight studies that included comprehensive and consistent trends data. When trends data were weighted according to population size of individual countries, an increase in yearly incidence of 0.27 cases per 100 000 people was observed. Staphylococci and streptococci were the most common pathogens identified. The rate of surgical intervention ranged from 10.2% to 60.0%, and the rate of inpatient mortality ranged from 14.3% to 17.5%. In six studies that examined the rate of injection drug use, five of them reported a rate of less than 10%. Conclusion Based on findings from our systematic review, IE incidence in Europe has doubled over the past two decades in Europe. Multiple factors are likely responsible for this striking increase. Trial registeration number CRD42020191196.

Abstract Background The objective of this paper was to examine temporal changes of infective endocarditis (IE) incidence and epidemiology in North America. Methods A systematic review was conducted at Mayo Clinic, Rochester. Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus, and Web of Science were searched for studies published between January 1, 2000, and May 31, 2020. Four referees independently reviewed all studies, and those that reported a population-based incidence of IE in patients aged 18 years and older in North America were included. Results Of 8588 articles screened, 14 were included. Overall, IE incidence remained largely unchanged throughout the study period, except for 2 studies that demonstrated a rise in incidence after 2014. Five studies reported temporal trends of injection drug use (IDU) prevalence among IE patients with a notable increase in prevalence observed. Staphylococcus aureus was the most common pathogen in 7 of 9 studies that included microbiologic findings. In-patient mortality ranged from 3.7% to 14.4%, while the percentage of patients who underwent surgery ranged from 6.4% to 16.0%. Conclusions The overall incidence of IE has remained stable among the 14 population-based investigations in North America identified in our systematic review. Standardization of study design for future population-based investigations has been highlighted for use in subsequent systematic reviews of IE.

Objectives: Clinicians need to identify which patients presenting with S. aureus bacteremia (SAB) have underlying cardiovascular implantable electronic device (CIED) infection and therefore need device extraction. The goal of this study was to identify clinical predictors of CIED infection in patients presenting with SAB. Methods: We retrospectively reviewed all cases of SAB in CIED recipients at Mayo Clinic from Jan 2001 to Dec 2011. CIED infection was defined using clinical, microbiologic and echocardiographic criteria. Patients who presented with clinical signs of CIED pocket infection were excluded. A multivariable model was developed to identify independent predictors of CIED infection. Model discrimination was summarized using the area under a receiver operating characteristics curve (AUC). Results: Among the 131 patients with SAB and CIED, 45 (34%) had underlying CIED infection. Permanent pacemaker (PPM) devices (OR 3.90, 95% CI 1.65-9.23, p=0.002), >1 device-related procedure (OR 3.30, 95% CI 1.23-8.86, p=0.018), and duration of SAB ≥4 days (OR 5.54, 95% CI 3.32-13.23, p <0.001) were independently associated with an increased risk of CIED infection. The AUC for this multivariable model was 0.79 indicating good discriminatory capacity to separate SAB patients with and without CIED infection. Various combinations of these three features and the corresponding predicted probabilities of CIED infection are summarized in Table. Conclusions: An individual patient’s risk of underlying CIED infection can be calculated based on the type of device, number of device-related procedures, and duration of SAB. Patients without any of these high-risk features have very low risk of underlying CIED infection and may be monitored closely without immediate device extraction.

Background: In 2007, the American Heart Association (AHA) infective endocarditis (IE) prevention guidelines recommended that antibiotic prophylaxis before invasive dental procedures for the “moderate risk” (MR) group, which represented the bulk of patients who were to receive prophylaxis before 2007, be eliminated. This decision was met with much concern among some healthcare providers and that concern persists today. We therefore evaluated dental office records in Olmsted County (OC), Minnesota to determine whether patients included in the MR group continue to receive antibiotic prophylaxis despite the 2007 AHA recommendations. Methods: Eligible patients include all adult (≥18 years) residents of OC, classified as having MR cardiac condition for IE (i.e. mitral valve prolapse [MVP], bicuspid aortic valve [BAV], hypertrophic obstructive cardiomyopathy [HOCM], acquired valvular dysfunction [AVD]), with at least one dental visit between January 1, 2005 and June 1, 2015. Eight dental offices located within OC were sampled to identify both dental procedures and whether antibiotic prophylaxis was administered according to AHA guidelines. Results: We identified 334 MR patients. Approximately 62% of MR patients received antibiotic prophylaxis prior to the change in AHA guidelines in 2007. There was a decrease to 7% post-2007 AHA guidelines (P<.001). The magnitude of decline was greater among visits for dental cleanings (from 63% to 6%), as compared to other invasive procedures (57% to 11%; P=0.003) (Figure 1). AVD was the most common cardiac condition (85%), followed by MVP (8%), and BAV (4%). Conclusion: Following publication of the 2007 AHA IE prevention guidelines, there was a rapid, 9-fold decrease in antibiotic prophylaxis in patients with MR cardiac conditions who underwent invasive dental procedures in OC. These data are also critical as we attempt to evaluate the impact, if any, of this practice on the incidence of IE due to viridans group streptococci.

AbstractBackgroundOptimal timing of cardiovascular implantable electronic device (CIED) re‐implantation following device removal due to infection is undefined. Multinational guidelines reflect this and include no specific recommendation for this timing, while others have recommended waiting at least 14 days in cases of CIED related infective endocarditis (CIED‐IE). The current work seeks to clarify this issue.MethodsWe retrospectively reviewed institutional data at Mayo Clinic, Minnesota of patients aged ≥ 18 years who developed CIED‐IE from January 1, 1991 to February 1, 2016. CIED‐IE was defined as echocardiogram reported device lead or valvular vegetation. Regression analyses were used to relate the risk of clinical outcomes to the interval between CIED removal and re‐implantation and the location of vegetations.ResultsA total of 109 patients met study inclusion criteria. A majority (68.8%) of patients were men and the median age was 68.0 years. Transoesophageal echocardiogram (TEE) was performed in 95.4% of patients, with valve vegetations detected in 33.9% (n = 37). Survival analysis comparing patients in whom device re‐implantation was < 14 days vs. ≥14 days, and further categorized by those with and without valve vegetation, showed a significant difference (P = 0.028); patients with valve vegetation and reimplantation interval < 14 days had the lowest (58.7%) 12‐month survival. When adjusted for valve vegetation, longer time interval for reimplantation trended toward increased hospital length of stay (P = 0.079).ConclusionOur findings suggest that the recommended 14‐day delay between CIED extraction and re‐implantation in CIED‐IE patients is associated with a survival benefit, but longer length of hospital stay following re‐implantation.

Introduction: Cardiovascular implantable electronic devices (CIED) infections are frequently complicated with bloodstream infection (BSI). Complete device removal and prolonged antimicrobial therapy is essential for cure. The frequency of persistent BSI after source control (device extraction) is not well described. This study aims to assess the utility of repeat blood cultures (BC) after device extraction as recommended by the American Heart Association (AHA) guidelines. Methods: We selected patients who presented with BSI in the setting of CIED infection and underwent device removal at Mayo Clinic Rochester between 2012 and 2017. Cases where BC were not drawn prior to extraction, or repeated within 72 hours of device extraction, or met criteria for contamination were excluded. Results: Of 656 patients who underwent CIED extraction for device infection, 190 with post-extraction BC met study criteria. Among the final study cohort (Table 1), 159 patients had negative BC, while 31 had positive BC following CIED extraction. Pre-extraction, the most common causative organism was Staphylococcus aureus (91/190, 48%) (Figure 1a). Post-extraction, 22 of the 31 (71%) cases of persistent BSI were due to S. aureus (Fig 1b). The median duration of BSI was not significantly different between negative and positive BC groups (3 versus 4 days, p=0.92). Conclusions: Majority of patients had resolution of BSI after CIED extraction. S. aureus was the most common cause of persistent BSI post-extraction. Our findings support the AHA guidelines of repeating BC after device extraction, especially for S aureus .

Introduction: Practice guidelines recommend use of subcutaneous implantable cardioverter-defibrillators (ICD) in patients (pts) at risk of sudden cardiac death and high risk for infection. This has prompted a need to better identify pts at high risk of infection to assist in de novo device selection. The objective of this study is to estimate infection incidence in de novo transvenous (TV) ICD implants and assess risk factors associated with infection in a large Medicare population. Methods: A retrospective cohort study was conducted using 100% Medicare administrative and claims data to identify pts who underwent de novo TV-ICD implantation between 7/2016 and 1/2018. Device-related infection within 2 years of implantation was identified using ICD-10 diagnosis and procedure codes. Baseline pt factors associated with infection were identified by univariable logistic regression analysis of all variables of interest, including factors in Charlson and Elixhauser comorbidity indices, followed by stepwise selection criteria with a p≤0.25 for inclusion in a multivariable model and a backwards, stepwise elimination process with p≤0.1 to remain in the model. A time-to-event analysis was also conducted. Results: Among 26,742 pts with de novo TV-ICD, 519 (1.9%) had a device-related infection over 2 years. The mean pt age with and without infection was 68 and 71 years, respectively. While more than half (54%) of infections occurred within 90 days post implant, infections continued to be diagnosed with 16% of infections occurring between years 1 and 2. Multivariable analysis revealed several significant predictors of infection (Figure) including age <70 years, end stage renal disease with chronic dialysis and diabetes with complications. Conclusion: The rate of de novo TV-ICD infection in a large real-world Medicare population is clinically significant. The factors associated with increased infection risk identified here can be used to help determine device selection.

Abstract Background A population-based study of infective endocarditis (IE) in Olmsted County, Minnesota, provides a unique opportunity to define temporal and seasonal variations in IE incidence over an extended time period. Methods This was a population-based review of all adults (≥18 years) residing in Olmsted County, Minnesota, with definite or possible IE using the Rochester Epidemiology Project from January 1, 1970, through December 31, 2018. Poisson regression was used to characterize the trends in IE incidence; models were fitted with age, sex, calendar time, and season, allowing for nonlinearity and nonadditivity of their effects. Results Overall, 269 cases of IE were identified over a 49-year study period. The median age of IE cases was 67.2 years, and 33.8% were female. The overall age- and sex-adjusted incidence of IE was 7.9 cases per 100 000 person-years (95% CI, 7.0–8.9), with corresponding rates of 2.4, 2.4, 0.9, and 0.7 per 100 000 person-years for Staphylococcus aureus, viridans group streptococci (VGS), Enterococcus species, and coagulase-negative staphylococci IE, respectively. Temporal trends varied by age, sex, and season, but on average IE incidence increased over time (P = .021). Enterococcal IE increased the most (P = .018), while S. aureus IE appeared to increase but mostly in the winter months (P = .018). Between 1996 and 2018, the incidence of VGS IE was relatively stable, with no statistically significant difference in the trends before and after the 2007 AHA IE prevention guidelines. Conclusions Overall, IE incidence, and specifically enterococcal IE, increased over time, while S. aureus IE was seasonally dependent. There was no statistically significant difference in VGS IE incidence in the periods before and after publication of the 2007 AHA IE prevention guidelines.