A Contemporary Population-Based Profile of Infective Endocarditis Using the Expanded Rochester Epidemiology Project.

OBJECTIVE: To develop a contemporary profile of infective endocarditis (IE) among a population in 6 counties of Olmsted, Dodge, Mower, Steele, Waseca, and Freeborn in southern Minnesota between 2014 and 2018. PATIENTS AND METHODS: All possible and definite cases of IE (≥18 years) among residents of 6 counties in southern Minnesota, including Olmsted County, diagnosed between January 1, 2014, and December 31, 2018, were included in this retrospective, population-based investigation, using the Expanded Rochester Epidemiology Project (E-REP). RESULTS: Overall, 137 patients with IE developed incident IE in the 6-county region, corresponding to an age- and sex-adjusted incidence rate of 11.9 per 100,000 person-years. Men had a significantly higher incidence of IE (17.9 vs 6.8 per 100,000 person-years), and rates increased exponentially with age in both sexes. The median age of incident cases was 68.2 years, and 67.9% were male patients. The percentage of patients with histories of injection-drug use was low, at 6.7%. Bicuspid aortic valve was the most common (9.6%) native valve predisposing condition. Staphylococcus aureus was identified as the predominant pathogen in the overall group (34.8%), with viridans-group streptococci accounting for only 19.3% cases. Central nervous system and musculoskeletal complications were common. The 30-day readmission rate was 27.9%, and the 6-month mortality rate was 31.8%. CONCLUSION: To our knowledge, this is the first time that the population-based E-REP has been used to determine an age- and sex-adjusted IE incidence. Older male patients predominated, and S aureus was the most common pathogen. Based on these findings, it is not surprising that IE complications were frequently seen.

End-of-Therapy Echocardiography May Not Be Needed in All in Patients With Endocarditis.

BACKGROUND: The American Heart Association (AHA) guidelines for infective endocarditis (IE) management recommend end-of-therapy (EOT) echocardiography (ETE) to "establish a new baseline" and based on "expert opinion." METHODS: Medical records of IE patients treated between January 2005 and December 2011 were reviewed. Utilization of ETE and cumulative incidence of re-treatment with antimicrobials or cardiovascular surgery (re-Rx/CVS) within 1 year after EOT were evaluated. RESULTS: A total of 243 patients completed clinical follow-up at EOT and 170 at 1 year after EOT. One hundred seventy-seven of 243 (72.8%) underwent ETE, the majority (51.4%) transthoracic echocardiography. One hundred thirty-three of 177 (75.1%) were without new/worsened signs or symptoms (new/w-SSx). One hundred forty-one of 177 (79.7%) overall and 117/133 (87.9%) patients without new/w-SSx had no new ETE findings as compared with initial echocardiography. Among 36/177 (20.3%) with new ETE findings, 20/36 (55.6%) had new/w-SSx; ETE findings were more likely in patients with new/w-SSx (39.2% vs 8.3%; P < 0.001) at EOT. Patients were at increased risk of re-Rx/CVS with either new ETE findings (hazard ratio [HR], 25.86; 95% confidence interval [CI], 7.64-87.56; P < .001) or new/w-SSx (HR, 5.35; 95% CI, 2.87-9.95; P < .001). The highest risk of re-Rx/CVS was in patients with both new/w-SSx and new ETE findings (HR, 45.94; 95% CI, 19.07-110.71). Conversely, only 7/187 (3.4%) patients without new/w-SSx who had an ETE required re-Rx/CVS. CONCLUSIONS: The majority of patients without new/w-SSx at EOT will not have new ETE findings or need re-Rx/CVS within 1 year after EOT. EOT new/w-SSx is associated with new ETE findings and predicts the need for re-Rx/CVS. Further study is needed to determine whether patients without new/w-SSx need ETE.

Prosthetic Joint Infection due to Actinomyces species: A case series and review of literature.

Background: Actinomyces prosthetic joint infections (APJIs) are rare and optimal medical and surgical treatment strategies are unknown. The purpose of our study was to characterize the demographics, risk factors, management and outcomes of patients with PJIs due to Actinomyces spp. Methods: Using a retrospective cohort study design, the medical records of all patients with Actinomyces spp. total hip or knee arthroplasty infection (APJI) seen at a single institution between January 1, 1969 and December 31, 2016 were reviewed. We abstracted information including patient demographics, co-morbidities, joint age, surgical history, microbiology, management and outcomes. A simultaneous literature search via PubMed was performed to identify cases of APJI published in literature and a descriptive analysis was performed. Results: Eleven cases were identified over a 47 year study period at our institution. Seven patients (64%) were female. The median age at the time of diagnosis of infection was 71 years (range, 57-89). The knee was involved in six cases (55%) followed by the hip in 5 (45 %) cases. Three cases had dentures, broken teeth, or poor dentition. Actinomyces odonotlyticus was the most commonly found subspecies at our institution. Median ESR and CRP values were 61mm/hr and 64 mg/L respectively. Eight (72%) patients were managed with 2 stage exchange. Most patients received a course of beta-lactam therapy for 6 weeks. Ten cases (91%) were free of failure after a median duration of follow-up of 2 years (range, 0.67 - 5 years). The median duration from joint arthroplasty to the onset of symptoms was 162 days, range (20-3318). Six (54%) had a history of prior PJI with a different microorganism at the same joint site and 4 patients had history of prior 2 stage exchange (36%). In the literature group, we identified 12 cases and the most common subspecies was Actinomyces israelii; most patients underwent two stage exchange and were treated with 6 weeks of beta lactam antibiotics. Conclusions: Based on our observational study, Actinomyces PJI presents as a late complication of TJR, may be associated with prior PJI at the index joint and antecedent dental manipulation may portend as an additional risk factor. Treatment includes two stage exchange and beta- lactam therapy for 6weeks. These results will help clinicians in improved understanding and management of APJIs which although are rare but warrant special attention as population with implanted joint arthroplasties continues to rise.

Predictors of Bloodstream Infection in Patients Presenting With Cardiovascular Implantable Electronic Device Pocket Infection.

BACKGROUND: Generator pocket infection is the most frequent presentation of cardiovascular implantable electronic device (CIED) infection. We aim to identify predictors of underlying bloodstream infection (BSI) in patients presenting with CIED pocket infection. METHODS: We retrospectively reviewed all adults with CIED pocket infection cared for at our institution from January 2005 through January 2016. The CIED pocket infection cases were then subclassified as with or without associated BSI. Variables with P values <.05 at univariate analysis were included in a multivariable model to identify independent predictors of underlying BSI. RESULTS: We screened 429 cases of CIED infection, and 95 met the inclusion criteria. Of these, 68 cases (71.6%) were categorized as non-BSI and 27 (28.4%) as BSI. There were no statistically significant differences in patient comorbid conditions or device characteristics between the 2 groups. In multivariable analysis, the presence of systemic inflammatory response syndrome criteria (tachycardia, tachypnea, fever or hypothermia, and leukocytosis or leukopenia) and hypotension were independent predictors of underlying BSI in patients presenting with CIED pocket infection. Overall, patients in the non-BSI group who did not receive pre-extraction antibiotics had a higher frequency of positive intraoperative pocket/device cultures than those with pre-extraction antibiotic exposure (79.4% vs 58.6%; P = .06). CONCLUSIONS: Patients with CIED pocket infection who meet systemic inflammatory response syndrome criteria and/or are hypotensive at admission are more likely to have underlying BSI and should be started on empiric antibiotics after blood cultures are obtained. If these features are absent, it may be reasonable to withhold empiric antibiotics to optimize yield of pocket/device cultures during extraction.

Clinical Presentation, Management, and Outcomes of Cardiovascular Implantable Electronic Device Infections Due to Gram-Negative Versus Gram-Positive Bacteria.

OBJECTIVE: To describe and compare the clinical presentation, management, and outcomes of cardiovascular implantable electronic device (CIED) infections due to gram-negative bacteria (GNB) and CIED infections due to gram-positive bacteria (GPB). PATIENTS AND METHODS: We retrospectively reviewed all CIED infection cases at Mayo Clinic from January 1, 1992, through December 31, 2015. Cases were classified based on positive microbiology data from extracted devices or blood cultures. RESULTS: Of the 623 CIED infections during the study period, 31 (5.0%) were caused by GNB and 323 (51.8%) by GPB. Patients in the GNB group were more likely to present with local inflammatory findings at the pocket site (90.3% vs 72.4%; P=.03). All patients with bacteremia due to GNB had concomitant pocket infection compared with those with GPB (100% vs 33.9%; P=.002). After extraction, 41.9% of patients in the GNB group were managed with oral antibiotics vs 2.4% in the GPB group (P<.001). There were no statistically significant differences in infection relapse/recurrence or 1-year survival rates between the 2 groups. CONCLUSION: Compared with CIED infections caused by GPB, those due to GNB are more likely to present with pocket infection. Device-related GNB bacteremia almost always originates from the generator pocket. After extraction, oral antibiotic drug therapy may be a reasonable option in select cases of pocket infections due to GNB. No difference in outcomes was observed between the 2 groups.

Variable Significance of Brain MRI Findings in Infective Endocarditis and Its Effect on Surgical Decisions.

OBJECTIVE: To determine how brain magnetic resonance imaging (MRI) findings impact clinical outcomes in patients with infective endocarditis (IE) and to propose a management algorithm for patients with neurologic symptoms who are candidates for valve surgery (VS). PATIENTS AND METHODS: Data from our center were retrospectively reviewed for patients hospitalized with IE between January 1, 2007, and December 31, 2014. Outcomes were postoperative intracerebral hemorrhage (ICH), 6-month mortality, and functional outcome at last follow-up as described by the modified Rankin Scale (mRS) score. Good outcome was defined as an mRS score of 2 or less. RESULTS: A total of 361 patients with IE were identified, including 127 patients (35%) who had MRI. One hundred twenty-six of 361 patients (35%) had neurologic symptoms, which prompted MRI in 79 of 127 patients (62%); 74 of 79 (94%) had acute or subacute MRI abnormalities. One patient with subarachnoid and multifocal ICH on MRI developed postoperative ICH. Patients with VS despite MRI abnormalities had lower 6-month mortality (odds ratio [OR], 0.17; 95% CI, 0.06-0.48; P<.001) and better functional outcome (OR, 4.43; 95% CI, 1.51-13.00; P=.005). Irrespective of VS, lobar or posterior fossa ICH on MRI was associated with 6-month mortality (OR, 3.58; 95% CI, 1.22-10.50; P=.02) and territorial ischemic stroke was inversely associated with good mRS (OR, 0.29; 95% CI, 0.13-0.66; P=.002). In neurologically asymptomatic patients who had VS, MRI findings did not impact 6-month mortality or functional outcomes. CONCLUSION: Magnetic resonance imaging detects a large number of abnormalities in patients with IE. Preoperative lobar hematoma and large territorial stroke determine outcome irrespective of VS. When indicated, VS increases the odds of a good outcome despite MRI abnormalities.

Prediction of the Renal Elimination of Drugs With Cystatin C vs Creatinine: A Systematic Review.

Serum cystatin C has been proposed as a kidney biomarker to inform drug dosing. We conducted a systematic review to synthesize available data for the association between serum cystatin C and drug pharmacokinetics, dosing, and clinical outcomes in adults (≥18 years). PubMed, Ovid MEDLINE, Ovid EMBASE, EBSCO CINAHL, and Scopus were systematically searched from 1946 to September 2017 to identify candidate studies. Studies of cystatin C as a predictor for acute kidney injury or for management of contrast-associated acute kidney injury were excluded. Also, studies were excluded if drug concentrations were unavailable and if a reference standard for drug dosing (eg, serum creatinine) was not concurrently reported. The outcomes of interest included drug clearance (L/h), concentrations (mg/L), target level achievement (%), therapeutic failure (%), and drug toxicity (%). We included 28 articles that evaluated 16 different medications in 3455 participants. Vancomycin was the most well-studied drug. Overall, cystatin C-based estimated glomerular filtration rate (eGFRCystatin C) was more predictive of drug levels and drug clearance than eGFRCreatinine. In only one study were target attainment and outcomes compared between 2 drug-dosing regimens, one based on eGFRCreatinine-Cystatin C and one dosed with the Cockcroft-Gault creatinine clearance equation. Compared with eGFRCreatinine, use of eGFRCystatin C to predict elimination of medications via the kidney was as accurate, if not superior, in most studies, but infrequently were data on target attainment or clinical outcomes reported. Drug-specific dosing protocols that use cystatin C to estimate kidney function should be tested for clinical application.

Incidence of Acute Kidney Injury Among Critically Ill Patients With Brief Empiric Use of Antipseudomonal ß-Lactams With Vancomycin.

BACKGROUND: Nephrotoxins contribute to 20%-40% of acute kidney injury (AKI) cases in the intensive care unit (ICU). The combination of piperacillin-tazobactam (PTZ) and vancomycin (VAN) has been identified as nephrotoxic, but existing studies focus on extended durations of therapy rather than the brief empiric courses often used in the ICU. The current study was performed to compare the risk of AKI with a short course of PTZ/VAN to with the risk associated with other antipseudomonal ß-lactam/VAN combinations. METHODS: The study included a retrospective cohort of 3299 ICU patients who received ≥24 but ≤72 hours of an antipseudomonal ß-lactam/VAN combination: PTZ/VAN, cefepime (CEF)/VAN, or meropenem (MER)/VAN. The risk of developing stage 2 or 3 AKI was compared between antibiotic groups with multivariable logistic regression adjusted for relevant confounders. We also compared the risk of persistent kidney dysfunction, dialysis dependence, or death at 60 days between groups. RESULTS: The overall incidence of stage 2 or 3 AKI was 9%. Brief exposure to PTZ/VAN did not confer a greater risk of stage 2 or 3 AKI after adjustment for relevant confounders (adjusted odds ratio [95% confidence interval] for PTZ/VAN vs CEF/VAN, 1.11 [.85-1.45]; PTZ/VAN vs MER/VAN, 1.04 [.71-1.42]). No significant differences were noted between groups at 60-day follow-up in the outcomes of persistent kidney dysfunction (P = .08), new dialysis dependence (P = .15), or death (P = .09). CONCLUSION: Short courses of PTZ/VAN were not associated with a greater risk of short- or 60-day adverse renal outcomes than other empiric broad-spectrum combinations.

Sonication Culture of Antimicrobial Agent-Containing Cement Spacers Removed during Staged Revisions for Arthroplasty Infection.

Diagnosis of persistent infection at the time of reimplantation for staged revision of infected arthroplasties is challenging. Implant sonication culture for the diagnosis of prosthetic joint infection (PJI) has improved sensitivity compared to standard periprosthetic tissue culture. We report our experience with periprosthetic tissue culture and sonication culture of antimicrobial agent-containing cement spacers (ACSs) collected during second stages of staged revisions for arthroplasty infection. We studied 87 ACSs from 66 patients undergoing two-stage revision arthroplasty for PJI submitted for sonication culture, along with conventional periprosthetic tissue cultures. Two or more positive periprosthetic tissue cultures with the same organism were considered a positive tissue culture. For sonication culture, ≥20 CFU of bacteria per 10 ml of sonicate fluid was considered positive. The sensitivity and specificity of periprosthetic tissue and ACS sonication culture in detecting persistent infection, as well as their association with outcome, were assessed. Persistent infection occurred in 26% of cases. Periprosthetic tissue and sonicate fluid culture had specificities of 96.3 and 100% (P = 0.50), respectively, and sensitivities of 31.6 and 26.3% (P = 1.00), respectively, for the diagnosis of persistent infection. Thirteen subjects deemed not to have persistent infection at time of reimplantation and who had negative periprosthetic tissue and sonicate fluid cultures subsequently developed overt infection. Sonication culture of cement spacers identifies a similar proportion of patients with persistent infection during staged revisions, as detected by periprosthetic tissue cultures; both have low sensitivities to detect persistent infection.

Comparison of Dual ß-Lactam therapy to penicillin-aminoglycoside combination in treatment of Enterococcus faecalis infective endocarditis.

BACKGROUND: Dual ß-lactam therapy and a penicillin-aminoglycoside combination are first line regimens in the treatment of penicillin-susceptible Enterococcus faecalis infective endocarditis (EFIE). Our aim was to compare ampicillin plus ceftriaxone (A+C) to ampicillin plus gentamicin (A+G) in the treatment of EFIE. METHODS: This was a retrospective cohort study of adults (≥18 years) patients diagnosed with EFIE at Mayo Clinic campuses in Rochester, Minnesota, and Phoenix, Arizona and treated with either A+C or A+G. Main outcome measurements were 1 year mortality, nephrotoxicity, and EFIE relapse rates. RESULTS: Eighty-five cases of EFIE were included in this investigation. The majority (n=67, 79%) of patients received A+G while 18 (21%) patients received A+C as initial treatment. On admission, patients who received A+C had a higher Charlson Comorbidity Index (median [IQR], 4 [3, 4 vs. 2 [1, 4]; P=.008) and a higher baseline serum creatinine (median [IQR], 1.2 [0.9, 1.6] vs. 0.9 [0.8, 1.2] mg/dL, P=.020). The 1 year mortality rates were similar for both treatment groups, 17% vs. 17%, P=.982. Each group had 1 case of relapsing EFIE. Patients who received A+G had worse kidney function outcome demonstrated by a greater increase in serum creatinine at end of therapy (median [IQR] difference, +0.4 [0.2, 0.8] vs. -0.2 [-0.3, 0.1] mg/dL, P≤.001). CONCLUSION: A+C appears to be a safe and efficacious regimen in the treatment of EFIE. Patients treated with A+C had lower rates of nephrotoxicity and no differences in relapse rate and 1-year mortality as compared to that of the A+G group.

Diagnostic evaluation and management of culture-negative cardiovascular implantable electronic device infections.

BACKGROUND: Culture-negative (CN) cardiovascular implantable electronic device (CIED) infections represent a significant management challenge for clinicians with no specific guidelines addressing this subgroup of patients. The aim of the current investigation is to report our institutional experience of CN CIED infections and propose a systematic approach to diagnostic evaluation and management of these complicated cases based on our observations. METHODS: We retrospectively screened all CIED infection cases at Mayo Clinic from 2005 through 2017. Using standardized criteria to define significant microbial growth, all patients with positive blood or pocket/device cultures were excluded. RESULTS: A total of 835 cases of CIED infection were screened, and of these, 47 (6%) met CN-CIED infection criteria. Majority of patients (77%) in this cohort had received antimicrobial therapy prior to device cultures with a median duration of 8 days. The most common presentation was device pocket infection (81%). All patients underwent device removal. Route of antibiotics was switched from oral to parenteral and spectrum of activity expanded from initial therapy in 23% of patients despite negative cultures. Majority of patients (80%) were dismissed on parenteral therapy. Adverse events attributed to intravenous antibiotic therapy were documented in 63% of the cases. No recurrence was reported and 6-month survival was 94.8%. CONCLUSIONS: Pocket and device cultures in suspected CIED infections may be negative due to preextraction oral antibiotics. However, frequently these patients are managed with broad-spectrum parenteral therapy postextraction.

Utility of cardiac computed tomography scanning in the diagnosis and pre-operative evaluation of patients with infective endocarditis.

Transesophageal echocardiography (TEE) is the gold standard imaging study used in the diagnosis of infective endocarditis (IE). Computed tomography angiography (CTA) has undergone rapid advancement as a cardiac imaging technique and has previously shown promise in small non-randomized studies for evaluation of IE. We hypothesized that cardiac CTA would perform similarly to TEE in the detection of endocarditic lesions and that there would be no difference in clinical outcomes whether the coronary arteries were evaluated by CTA or invasive coronary angiography (ICA). 255 adults who underwent surgery for IE at the Mayo Clinic Rochester between January 1, 2006 and June 1, 2014 were identified retrospectively. 251 patients underwent TEE and 34 patients underwent cardiac CTA. TEE had statistically higher detection of vegetations (95.6 vs. 70.0%, p < 0.0001) and leaflet perforations (81.3 vs. 42.9%, p = 0.02) as compared to cardiac CTA. For detection of abscess/pseudoaneurysm TEE had a similar sensitivity to cardiac CTA (90.5 vs. 78.4%, p = 0.21). There was no significant difference in peri-operative outcomes whether coronary arteries were evaluated by CTA or ICA. The greatest advantage of cardiac CT in the setting of IE is its ability to couple the detection of complex cardiac anatomic abnormalities with coronary artery delineation, serving two important components of the diagnostic evaluation, particularly among patients who will require surgical intervention due to IE complications. Cardiac CTA may be considered as an alternate coronary artery imaging modality in IE patients with low to intermediate risk of disease but meet guideline recommendations for coronary artery imaging.

Impacts of a care process model and inpatient electrophysiology service on cardiovascular implantable electronic device infections: a preliminary evaluation.

PURPOSE: Cardiovascular implantable electronic device infection (CIEDI) rates are rising. To improve outcomes, our institution developed an online care process model (CPM) and a specialized inpatient heart rhythm service (HRS). METHODS: This retrospective review compared hospital length of stay (LOS), mortality, and times to subspecialty consultation and procedures before and after CPM and HRS availability. RESULTS: CPM use was associated with shortened time to surgical consultation (median 2 days post-CPM vs. 3 days pre-CPM, p = 0.0152), pocket closure (median 4 vs. 5 days, p < 0.0001), and days to new CIED implant (median 7 vs. 8 days, p = 0.0126). Post-HRS patients were more likely to have a surgical consultation (OR 7.01, 95% CI 1.56-31.5, p = 0.011) and shortened time to pocket closure (coefficient - 2.21 days, 95% CI - 3.33 to - 1.09, p < 0.001), compared to pre-HRS. CONCLUSIONS: The CPM and HRS were associated with favorable outcomes, but further integration of CPM features into hospital workflow is needed.

Utility of Brain Magnetic Resonance Imaging in the Surgical Management of Infective Endocarditis.

BACKGROUND: Brain magnetic resonance imaging (MRI) is frequently obtained in patients with infective endocarditis, yet its utility in predicting outcomes for valve replacement surgery in patients is unknown. The objective of this study was to determine how brain MRI findings impact clinical management and outcomes. METHODS: Demographic and clinical data from electronic medical records at Mayo Clinic were retrospectively reviewed for patients hospitalized with definite or possible infective endocarditis according to the modified Duke criteria between January 1, 2007 and December 31, 2014. There were 364 patients included in the study. RESULTS: Cardiac valve replacement surgery was performed in 195 of 364 (53.6%) patients, and 95 (48.7%) of the surgical patients underwent preoperative MRI, which was associated with preoperative neurologic symptoms in 56 of 95 (58.9%) patients (odds ratio = 12.92; 95% confidence interval, 5.98-27.93; P <.001). Postoperative neurologic complications occurred in 24 of 195 (12.3%) patients, including new ischemic stroke in 4 of 195 (2.1%) and new intracerebral hemorrhage in 3 of 195 (1.5%). No patients with microhemorrhages developed postoperative hemorrhage. No significant differences existed in rates of postoperative complications between patients with and those without preoperative MRI. There were no substantial associations between preoperative MRI findings and postoperative neurologic complications, functional outcomes as described by the modified Rankin Scale score, or 6-month mortality. CONCLUSIONS: In patients undergoing valve replacement surgery, preoperative MRI findings were not associated with differences in postoperative outcomes, irrespective of finding or timing of valve replacement surgery.

Effect of the American Heart Association 2007 Guidelines on the Practice of Dental Prophylaxis for the Prevention of Infective Endocarditis in Olmsted County, Minnesota.

OBJECTIVE: To determine the adherence of dental providers to the 2007 American Heart Association (AHA) infective endocarditis prevention guidelines regarding antibiotic drug administration before invasive dental procedures. PATIENTS AND METHODS: The study included all adults (≥18 years old) with a moderate-risk (MR) or high-risk (HR) cardiac condition who received dental care at participating dental offices from January 1, 2005, through June 1, 2015, in Olmsted County, Minnesota. Data collected included the date and type of dental procedure performed and receipt of antibiotic prophylaxis (AP). RESULTS: A total of 1351 patients underwent 8854 dental visits at participating dental offices during the study period; 1236 patients had an MR cardiac condition and 115 had an HR condition. The percentage of visits in which antibiotic drugs were used for indicated dental procedures in the MR group declined from 64.6% before to 8.6% after publication of the 2007 AHA guidelines (P<.001); for the HR group, AP declined from 96.9% before to 81.3% after publication of the guidelines (P=.02). CONCLUSION: In this historical cohort in Olmsted County there was a statistically significant reduction in AP in the MR group before invasive dental procedures. In addition, there was an unanticipated significant reduction in AP in the HR group after publication of the 2007 AHA guidelines. These findings can be used to provide feedback and education to medical and dental professionals who are involved in decision making regarding the use of dental prophylaxis for their patients.

A Novel Prosthetic Joint Infection Pathogen, Mycoplasma salivarium, Identified by Metagenomic Shotgun Sequencing.

Defining the microbial etiology of culture-negative prosthetic joint infection (PJI) can be challenging. Metagenomic shotgun sequencing is a new tool to identify organisms undetected by conventional methods. We present a case where metagenomics was used to identify Mycoplasma salivarium as a novel PJI pathogen in a patient with hypogammaglobulinemia.

Outcomes in Patients With Cardiovascular Implantable Electronic Device Infection Managed With Chronic Antibiotic Suppression.

BACKGROUND.: Most cardiovascular implantable electronic device (CIED) recipients are elderly, have multiple comorbid conditions, and are at increased risk of CIED infection (CIEDI). Current guidelines recommend complete device removal in patients with CIEDI to prevent relapse and mortality. However, comorbidities or other factors may preclude device removal, thus prompting a nonsurgical approach that includes chronic antibiotic suppression (CAS). There are limited data on outcomes of patients receiving CAS for CIEDI. METHODS.: We retrospectively screened 660 CIEDI cases from 2005 to 2015 using electronic health records and a CIEDI institutional database and identified 48 patients prescribed CAS. Primary outcomes were infection relapse and survival. RESULTS.: The median age was 78 years, and 73% (35/48) were male. The median Charlson comorbidity index was 4. Common pathogens were coagulase-negative staphylococci (21%, 10/48) and methicillin-sensitive Staphylococcus aureus (19%, 9/48). At 1 month after hospitalization, 25% (12/48) of patients had died, of whom only 1 initiated CAS; 67% (8/12) of these had staphylococcal infections. Of the 37 patients who initiated CAS, the most common antimicrobials were trimethoprim-sulfamethoxazole, penicillin, and amoxicillin (22%, 8/37 each). Estimated median overall survival was 1.43 years (95% confidence interval, 0.27-2.14), with 18% (6/33 survivors) developing relapse within 1 year. Of the 6 patients who relapsed, 2 (33%) subsequently underwent CIED extraction. CONCLUSION.: CAS is reasonable in select patients who are not candidates for complete device removal for attempted cure of CIEDI. Nevertheless, 1-month mortality in our sample of CAS-eligible patients was high and reflective of high rates of comorbid conditions.

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.

Beta-haemolytic streptococcal endocarditis: clinical presentation, management and outcomes.

BACKGROUND: Beta-haemolytic streptococcal (BHS) endocarditis is rare, but well-recognised for its high morbidity and mortality. This study sought to further characterise clinical features, management and outcomes of BHS endocarditis. METHODS: Retrospective review of all adultpatients (≥ 18 years old) with BHS endocarditis treated at the Mayo Clinic from 1 January 2000 to 31 December 2014. RESULTS: Forty-nine cases of BHS endocarditis were identified with a mean (± SD) age of 64 (± 14.9) years and 65% were males. The infection was community acquired in 92% of the cases, with a median (IQR) time to diagnosis from symptom onset of 6 days (5-10). Associated conditions included the presence of a prosthetic valve (41%), malignancy (33%) and diabetes mellitus (DM) (31%). Median (IQR) vegetation size was 12 mm (9-17 mm). In a univariate analysis patients with DM had larger vegetations, median (IQR) = 17 mm (10.5-26 mm) compared to non-diabetic patients, median (IQR) = 11 mm (8-15 mm) (p = 0.01). Septic brain emboli occurred in 43% of cases. Eighteen patients (37%) underwent early (within 30 days) surgery. All-cause 1 month and 6 month mortality rates were 25% and 31%, respectively. CONCLUSION: BHS endocarditis has an acute onset and is complicated by relatively large vegetations with a high rate of systemic embolisation. DM was the second most common associated medical condition and patients with DM had larger vegetations. Despite medical and surgical advances, mortality due to BHS endocarditis remains high, particularly within 30 days of diagnosis.