Infective Endocarditis Among High-risk Individuals Before and After the Cessation of Antibiotic Prophylaxis in Dentistry: A National Cohort Study.

BACKGROUND: A few years after the publication of the British guidelines, national recommendations were published by the Swedish Medical Products Agency in October 2012, promoting the cessation of antibiotic prophylaxis in dentistry for the prevention of infective endocarditis (IE). The aim of this study was to evaluate whether the incidence of oral streptococcal IE increased among high-risk individuals after October 2012. METHODS: This nationwide cohort study included all adult individuals (>17 years) living in Sweden from January 2008 to January 2018, with a diagnose code or surgical procedure code indicating high risk of IE. Cox proportional hazard models were performed to calculate adjusted ratios of oral streptococcal IE before and after October 2012 between high-risk individuals and references. RESULTS: This study found no increased incidence of oral streptococcal IE among high-risk individuals during the 5 years after the cessation, compared with before. Hazard rate ratios were 15.4 (95% confidence interval [CI]: 8.3-28.5) before and 20.7 (95% CI: 10.0-42.7) after October 2012 for prevalent high-risk individuals. Corresponding ratios for incident high-risk individuals were 66.8 (95% CI: 28.7-155.6) and 44.6 (95% CI: 22.9-86.9). Point estimates for interaction with time period were 1.4 (95% CI: .6-3.5) and 0.8 (95% CI: .5-1.3) for prevalent and incident high-risk individuals, respectively. CONCLUSION: The results suggest that the current Swedish recommendation not to administer antibiotic prophylaxis for the prevention of IE in dentistry has not led to an increased incidence of oral streptococcal IE among high-risk individuals.

Microbiological etiology in prosthetic valve endocarditis: A nationwide registry study.

BACKGROUND: Prosthetic valve endocarditis (PVE) is a feared complication after heart valve surgery. Studies on differences in bacteriology in various types of PVE are limited. OBJECTIVES: This study aimed to investigate the microbiology of PVE depending on the type of prosthetic valve and timing of diagnosis. METHODS: A retrospective study based on the Swedish Registry on Infective Endocarditis focusing on PVE was conducted. The cohort was divided into mechanical and bioprosthetic valves; into endocarditis localization in the aortic, mitral, or tricuspid valve; and into early and late PVE. The microbiology in these groups was compared. Predictors of Staphylococcus aureus as the cause of PVE were examined by multivariable logistic regression. RESULTS: A total of 780 episodes of PVE in 749 patients were compared regarding the distribution of causative microbiological agents. The most common agents included alpha-hemolytic streptococci (29%), S. aureus (22%), enterococci (14%), coagulase-negative staphylococci (CoNS) (12%), and Cutibacterium acnes (6%). S. aureus was more commonly found on mechanical valves compared to bioprosthetic ones (36% vs. 17%, p < 0.001) whereas alpha-hemolytic streptococci, enterococci, and CoNS were more common on bioprosthetic valves. There were no significant differences in the microbiology of PVE affecting mitral or aortic valves or in cases of early and late PVE. Predictors for S. aureus as the cause of PVE were end-stage renal disease, intravenous drug use, mechanical valve, and tricuspid localization of endocarditis. CONCLUSIONS: The type of prosthetic heart valve is associated with the causative pathogen. Patients with mechanical valves are more likely to have PVE caused by S. aureus.

Endocarditis due to Staphylococcus lugdunensis-a retrospective national registry-based study.

We present characteristics of infective endocarditis (IE) caused by Staphylococcus lugdunensis and compare with IE caused by Staphylococcus aureus and other CoNS, in the National Swedish Registry of IE (2008-2018). Thirty episodes of S. lugdunensis IE were registered, of which 21 cases affected native valves, and 7 patients were subjected to surgery. The mortality rate at 30 days was significantly higher for S. lugdunensis IE (20%, n = 6), than for IE caused by other CoNS (7%) or S. aureus (9%) p = 0.016. Septic embolisation was only reported in two cases (7%). The most common treatment was isoxazolyl penicillin (n = 18).

Infective endocarditis caused by HACEK group bacteria-a registry-based comparative study.

Infective endocarditis (IE) caused by bacteria within Haemophilus (excluding Haemophilus influenzae), Aggregatibacter, Cardiobacterium, Eikenella and Kingella (HACEK) is rare. This study aimed to describe clinical features of IE caused by HACEK genera in comparison with IE due to other pathogens. Cases of IE due to HACEK were identified through the Swedish Registry of Infective Endocarditis (SRIE). Clinical characteristics of IE cases caused by HACEK were compared with cases of IE due to other pathogens reported to the same registry. Ninety-six patients with IE caused by HACEK were identified, and this corresponds to 1.8% of all IE cases. Eighty-three cases were definite endocarditis, and the mortality rate was 2%. The median age was 63 years, which was lower compared to patients with IE caused by other pathogens (66, 70 and 73 years respectively, p ≤ 0.01). Patients with IE caused by Haemophilus were younger compared to patients with IE due to Aggregatibacter (47 vs 67 years, p ≤ 0.001). Patients with IE due to HACEK exhibited longer duration from onset of symptoms to hospitalization and had more prosthetic valve endocarditis compared to patients with IE due to Staphylococcus aureus (10 vs 2 days, p ≤ 0.001, and 35 vs 14%, p ≤ 0.001). This is, to date, the largest study on IE due to HACEK. Aggregatibacter was the most common cause of IE within the group. The condition has a subacute onset and often strikes in patients with prosthetic valves, and the mortality rate is relatively low.

Infective endocarditis after transcatheter aortic valve implantation: a nationwide study.

AIMS: Transcatheter aortic valve implantation (TAVI), now a common procedure to treat high-risk patients with severe aortic stenosis, has rapidly been expanding into younger and lower-risk populations, creating a need to better understand long-term outcome after TAVI. The aim of the present investigation was to determine the incidence, risk factors for, clinical presentation of, and outcome after prosthetic valve endocarditis (PVE) in patients treated with TAVI in a nationwide study. METHODS AND RESULTS: Three registries were used: a national TAVI registry, a national diagnosis registry, and a national infective endocarditis registry. Combining these registries made it possible to perform a nationwide, all-comers study with independent and validated reporting of PVE in 4336 patients between 2008 and mid-2018. The risk for PVE after TAVI was 1.4% (95% confidence interval 1.0-1.8%) the first year and 0.8% (0.6-1.1%) per year thereafter. One-year survival after PVE diagnosis was 58% (49-68%), and 5-year survival was 29% (17-41%). Body surface area, estimated glomerular filtration rate <30 mL/min/1.73 m2, critical pre-operative state, mean pre-procedural valve gradient, amount of contrast dye used, transapical access, and atrial fibrillation were identified as independent risk factors for PVE. Staphylococcus aureus was more common in early (<1 year) PVE. Infection with S. aureus, root abscess, late PVE, and non-community acquisition was associated with higher 6-month mortality. CONCLUSION: The incidence of PVE was similar to that of surgical bioprostheses. Compromised renal function was a strong risk factor for developing PVE. In the context of PVE, TAVI seems to be a safe option for patients. CLINICAL TRIAL REGISTRATION: NCT03768180 (http://clinicaltrials.gov/).

Infective endocarditis due to Streptococcus dysgalactiae: clinical presentation and microbiological features.

Knowledge of infective endocarditis (IE) caused by Streptococcus dysgalactiae (SD) is limited. This study aimed to identify the clinical and microbiological features of SD-caused IE and to investigate any possible synergy between penicillin and gentamicin on SD isolates. Cases of IE 2008-2016 due to SD reported to the Swedish Registry of Infective Endocarditis (SRIE) were identified. Isolates were emm typed and synergy between antibiotics was determined in time-kill experiments. Medical records were reviewed and SD-cases were compared to cases of IE due to other pathogens reported to the SRIE. Fifty cases of SD-caused IE were confirmed. emm types stC74a, stG62647, and stG643 were most commonly encountered. The patients had a median age of 74 years (range 38-93) and were significantly older compared to patients with Staphylococcus aureus-caused IE, (65 years (p = 0.003)). The median time to diagnosis from symptom onset was 1 day for patients with SD-caused IE which was less compared to patients with IE due to the other pathogens (2-15 days). Embolization was seen in 46% and the in-hospital mortality was 8%. Etest-based methods did not indicate any synergy between penicillin and gentamicin whereas synergy was noted for four out of nine isolates applying time-kill assays. This is the largest study of SD-caused IE, a condition with an acute onset predominantly affecting elderly people. Synergy between penicillin and gentamicin against some SD isolates was distinguished but the potential benefit of this must be weighed against the risk of aminoglycoside side effects.

Prosthetic valve endocarditis caused by Propionibacterium species: a national registry-based study of 51 Swedish cases.

Propionibacterium spp. are a rare cause of infective endocarditis (IE). The diagnosis is difficult because the bacteria are slow-growing and growth in blood cultures is often misinterpreted as contamination from the skin flora. The aim of this study was to describe all cases of Propionibacterium spp. endocarditis in the Swedish national registry of IE. The registry was searched for all cases of IE from 1995 to 2016 caused by Propionibacterium spp. Data concerning clinical characteristics, treatment, and outcome were registered. A total of 51 episodes of definitive prosthetic valve endocarditis (PVE) caused by Propionibacterium spp. were identified, comprising 8% of cases of PVE during the study period. Almost all cases (n = 50) were male. The median time from surgery to diagnosis of IE was 3 years. Most patients were treated mainly with beta-lactams, partly in combination with aminoglycosides. Benzyl-penicillin was the most frequently used beta-lactam. A total of 32 patients (63%) underwent surgery. Overall, 47 patients (92.1%) were cured, 3 (5.9%) suffered relapse, and 1 (2.0%) died during treatment. IE caused by Propionibacterium spp. almost exclusively affects men with a prosthetic valve and findings of Propionibacterium spp. in blood cultures in such patients favors suspicion of a possible diagnosis of IE. In patients with prosthetic valves, prolonged incubation of blood cultures up to 14 days is recommended. The prognosis was favorable, although a majority of patients required cardiac surgery during treatment. Benzyl-penicillin should be the first-line antibiotic treatment option for IE caused by Propionibacterium spp.

Clinical and microbiological features of infective endocarditis caused by aerococci.

PURPOSE: To define the clinical presentation of aerococcal infective endocarditis (IE) and the prevalence of synergy between penicillin and gentamicin on aerococcal isolates. METHODS: Cases of aerococcal IE between 2002 and 2014 were identified in the Swedish Registry of Infective Endocarditis (SRIE). MALDI-TOF MS was used to confirm species determination. The medical records were analysed and compared to cases reported to the SRIE caused by other pathogens. RESULTS: Sixteen cases of aerococcal IE, fourteen with Aerococcus urinae and two with Aerococcus sanguinicola, were confirmed. Etest-based methods and time-kill experiments suggested synergy between penicillin and gentamicin towards seven of fifteen isolates. The patients with aerococcal IE were significantly older than those with streptococci or Staphylococcus aureus IE. Most of the patients had underlying urinary tract diseases or symptoms suggesting a urinary tract focus of the infection. Seven patients with aerococcal IE presented with severe sepsis but ICU treatment was needed only in one patient and there was no fatality. Valve exchange surgery was needed in four patients and embolization was seen in three patients. CONCLUSIONS: This report is the largest on aerococcal IE and suggests that the prognosis is relatively favourable despite the fact that the patients are old and have significant comorbidities.

Influence of the timing of cardiac surgery on the outcome of patients with infective endocarditis and stroke.

BACKGROUND: The timing of cardiac surgery after stroke in infective endocarditis (IE) remains controversial. We examined the relationship between the timing of surgery after stroke and the incidence of in-hospital and 1-year mortalities. METHODS: Data were obtained from the International Collaboration on Endocarditis-Prospective Cohort Study of 4794 patients with definite IE who were admitted to 64 centers from June 2000 through December 2006. Multivariate logistic regression and Cox regression analyses were performed to estimate the impact of early surgery on hospital and 1-year mortality after adjustments for other significant covariates. RESULTS: Of the 857 patients with IE complicated by ischemic stroke syndromes, 198 who underwent valve replacement surgery poststroke were available for analysis. Overall, 58 (29.3%) patients underwent early surgical treatment vs 140 (70.7%) patients who underwent late surgical treatment. After adjustment for other risk factors, early surgery was not significantly associated with increased in-hospital mortality rates (odds ratio, 2.308; 95% confidence interval [CI], .942-5.652). Overall, probability of death after 1-year follow-up did not differ between 2 treatment groups (27.1% in early surgery and 19.2% in late surgery group, P = .328; adjusted hazard ratio, 1.138; 95% CI, .802-1.650). CONCLUSIONS: There is no apparent survival benefit in delaying surgery when indicated in IE patients after ischemic stroke. Further observational analyses that include detailed pre- and postoperative clinical neurologic findings and advanced imaging data (eg, ischemic stroke size), may allow for more refined recommendations on the optimal timing of valvular surgery in patients with IE and recent stroke syndromes.

Oral streptococcal infective endocarditis among individuals at high risk following dental treatment: a nested case-crossover and case-control study.

Background: It is not clear whether Viridans Group Streptococcal Infective Endocarditis (VGS-IE) among individuals at high risk is more frequent following bacteraemia caused by invasive dental procedures (IDPs) than after daily bacteraemia caused by chewing and tooth brushing. The aim of this nested study was to assess if VGS-IE was temporally associated with IDPs in a national cohort of individuals at high risk. Methods: This nested case-control and case-crossover study was based on a Swedish national cohort study of 76,762 individuals at high risk of IE due to complex congenital heart disease, prosthetic heart valve or previous IE. Participants were living in Sweden between July 1st, 2008 and January 1st, 2018. The frequency of IDPs during the 3 months before VGS-IE was calculated and compared to controls (sampled 1:10). A case-crossover study was conducted to account for residual confounders. Participants were identified using the national patient register, and IDPs were identified using the national dental health register. Findings: 98,247 IDPs were carried out in the cohort during the study period: 624 occasions of oral surgery, 44,190 extractions and 53,433 sessions of subgingival scaling. The study could not confirm that IDPs were more common among cases (4.6%) than controls (4.1%), OR = 1.22 [95% Confidence Interval (CI) 0.64-2.3], or during case- (3.3%) than reference periods (3.8%), OR = 0.89 [95% CI: 0.68-1.17]. Restricting the analysis to the period when cessation of antibiotic prophylaxis for the prevention of IE in Swedish dentistry was recommended, from the 1st of October 2012 to the 1st of January 2018, did not alter the results of the case-control study: OR 0.64, 95% CI: 0.20-2.09, or the case-crossover study: OR 0.58, 95% CI: 0.15-2.19. Interpretation: The study could not confirm that VGS-IE is associated with IDPs among individuals at high risk. A study with larger sample size could clarify whether there is a lack of association. The finding of a small (<5%) proportion of cases temporally associated with IDPs is similar to that of the previous large-scale study on IDPs and VGS-IE. Funding: Funding was provided by the Board of doctoral education at Karolinska Institutet, the Public Health Agency of Sweden, Folktandvården Stockholm AB, Steering Group for Collaborative Odontological Research at Karolinska Institutet and Stockholm City County, and the Swedish Dental Association.

Epidemiological Changes and Improvement in Outcomes of Infective Endocarditis in Europe in the Twenty-First Century: An International Collaboration on Endocarditis (ICE) Prospective Cohort Study (2000-2012).

INTRODUCTION: Infective endocarditis (IE) has undergone important changes in its epidemiology worldwide. METHODS: The study aimed to compare IE epidemiological features and outcomes according to predefined European regions and between two different time periods in the twenty-first century. RESULTS: IE cases from 13 European countries were included. Two periods were considered: 2000-2006 and 2008-2012. Two European regions were considered, according to the United Nations geoscheme for Europe: Southern (SE) and Northern-Central Europe (NCE). Comparisons were performed between regions and periods. A total of 4195 episodes of IE were included, 2113 from SE and 2082 from NCE; 2787 cases were included between 2000 and 2006 and 1408 between 2008 and 2012. Median (IQR) age was 63.7 (49-74) years and 69.4% were males. Native valve IE (NVE), prosthetic valve IE (PVE), and device-related IE were diagnosed in 68.3%, 23.9%, and 7.8% of cases, respectively; 52% underwent surgery and 19.3% died during hospitalization. NVE was more prevalent in NCE, whereas device-related IE was more frequent in SE. Higher age, acute presentation, hemodialysis, cancer, and diabetes mellitus all were more prevalent in the second period. NVE decreased and PVE and device-related IE both increased in the second period. Surgical treatment also increased from 48.7% to 58.4% (p < 0.01). In-hospital and 6-month mortality rates were comparable between regions and significantly decreased in the second period. CONCLUSIONS: Despite an increased complexity of IE cases, prognosis improved in recent years with a significant decrease in 6-month mortality. Outcome did not differ according to the European region (SE versus NCE).

ECG-gated computed tomography: a new role for patients with suspected aortic prosthetic valve endocarditis.

OBJECTIVES: The aim of this prospective study was to investigate the agreement in findings between ECG-gated CT and transoesophageal echocardiography (TEE) in patients with aortic prosthetic valve endocarditis (PVE). METHODS: Twenty-seven consecutive patients with PVE underwent 64-slice ECG-gated CT and TEE and the results were compared. Imaging was compared with surgical findings (surgery was performed in 16 patients). RESULTS: TEE suggested the presence of PVE in all patients [thickened aortic wall (n = 17), vegetation (n = 13), abscess (n = 16), valvular dehiscence (n = 10)]. ECG-gated CT was positive in 25 patients (93 %) [thickened aortic wall (n = 19), vegetation (n = 7), abscess (n = 18), valvular dehiscence (n = 7)]. The strength of agreement [kappa (95 % CI)] between ECG-gated CT and TEE was very good for thickened wall [0.83 (0.62-1.0)], good for abscess [0.68 (0.40-0.97)] and dehiscence [0.75 (0.48-1.0)], and moderate for vegetation [0.55 (0.26-0.88)]. The agreement was good between surgical findings (abscess, vegetation and dehiscence) and imaging for ECG-gated CT [0.66 (0.49-0.87)] and TEE [0.79 (0.62-0.96)] and very good for the combination of ECG-gated CT and TEE [0.88 (0.74-1.0)]. CONCLUSION: Our results indicate that ECG-gated CT has comparable diagnostic performance to TEE and may be a valuable complement in the preoperative evaluation of patients with aortic PVE.

Analysis of the impact of early surgery on in-hospital mortality of native valve endocarditis: use of propensity score and instrumental variable methods to adjust for treatment-selection bias.

BACKGROUND: The impact of early surgery on mortality in patients with native valve endocarditis (NVE) is unresolved. This study sought to evaluate valve surgery compared with medical therapy for NVE and to identify characteristics of patients who are most likely to benefit from early surgery. METHODS AND RESULTS: Using a prospective, multinational cohort of patients with definite NVE, the effect of early surgery on in-hospital mortality was assessed by propensity-based matching adjustment for survivor bias and by instrumental variable analysis. Patients were stratified by propensity quintile, paravalvular complications, valve perforation, systemic embolization, stroke, Staphylococcus aureus infection, and congestive heart failure. Of the 1552 patients with NVE, 720 (46%) underwent early surgery and 832 (54%) were treated with medical therapy. Compared with medical therapy, early surgery was associated with a significant reduction in mortality in the overall cohort (12.1% [87/720] versus 20.7% [172/832]) and after propensity-based matching and adjustment for survivor bias (absolute risk reduction [ARR] -5.9%, P<0.001). With a combined instrument, the instrumental-variable-adjusted ARR in mortality associated with early surgery was -11.2% (P<0.001). In subgroup analysis, surgery was found to confer a survival benefit compared with medical therapy among patients with a higher propensity for surgery (ARR -10.9% for quintiles 4 and 5, P=0.002) and those with paravalvular complications (ARR -17.3%, P<0.001), systemic embolization (ARR -12.9%, P=0.002), S aureus NVE (ARR -20.1%, P<0.001), and stroke (ARR -13%, P=0.02) but not those with valve perforation or congestive heart failure. CONCLUSIONS: Early surgery for NVE is associated with an in-hospital mortality benefit compared with medical therapy alone.

The relationship between cerebrovascular complications and previously established use of antiplatelet therapy in left-sided infective endocarditis.

BACKGROUND: Cerebrovascular complications (CVC) in infective endocarditis (IE) are common. The only established treatments to reduce the incidence of CVC in IE are antibiotics and in selected cases early cardiac surgery. Potential effects of previously established antiplatelet therapy are under debate. METHODS: In a prospective cohort study in Sweden and Demark, the influence of previously established antiplatelet therapy on CVC incidence and mortality in IE was assessed using logistic regression models. RESULTS: Among 684 left-sided definite IE episodes, 23.0% were seen in patients on established antiplatelet therapy (96% acetylsalicylic acid). Patients on antiplatelet therapy were older and significantly more often had a history of congestive heart failure prior to IE diagnosis. No difference in CVC rate was seen between patients with and without ongoing antiplatelet therapy (23.6% vs 25.0%, adjusted odds ratio (AOR) 0.8, 95% confidence interval (CI) 0.48-1.5). Ischemic stroke, which occurred in 115 episodes (16.8%), was the most common cerebral lesion, and haemorrhagic complications were seen in 16 (2.3%) patients without correlation to chronic antiplatelet therapy. Unadjusted 1-y mortality was higher for patients on previously established antiplatelet therapy (33.8% vs 24.1%, odds ratio (OR) 1.6, 95% CI 1.1-2.4), but after adjustment for covariables associated with mortality an opposite statistical trend was seen (AOR 0.7, 95% CI 0.4-1.1). CONCLUSIONS: The incidence of symptomatic CVC in IE patients was not reduced by previously established antiplatelet therapy. One-y mortality was higher in patients on antiplatelet therapy in univariate analysis, but after multivariable modelling this association was lost.

Comparing right- and left sided injection-drug related infective endocarditis.

The aim of the study was to compare background characteristics, microbiology and outcome of patients with right-sided and left-sided intravenous drug use (IDU) associated infective endocarditis (IE). A nationwide retrospective study using the Swedish Registry on Infective Endocarditis between 2008 and 2019 was conducted. A total of 586 people with IDU-IE were identified and divided into left-sided (n = 204) and right-sided (n = 382) IE. Descriptive statistics, Cox-regression and Kaplan-Meier survival estimates were used. The mean age of patients in the left-sided group was 46 years compared to 35 years in the right-sided group, p < 0.001. Left-sided IE had a higher proportion of females. Staphylococcus aureus was the causative pathogen in 48% of cases in the left-sided group compared to 88% in the right-sided group. Unadjusted and adjusted long-term survival was better in right-sided IE compared to left-sided IE. Independent predictors of long-term mortality were increasing age, end-stage renal disease, nosocomial infection, brain emboli and left-sided IE. Left-sided IE was common in people with IDU but the proportion of females with left-sided IE was low. S. aureus was twice as common in right-sided IE compared to left-sided IE, and the long-term prognosis of right sided IDU-associated IE was better compared to left-sided IE despite the fact that few were operated.

Surgery Is Underused in Elderly Patients With Left-Sided Infective Endocarditis: A Nationwide Registry Study.

Background Infective endocarditis is associated with higher mortality in elderly patients, but the role of surgery in this group has not been fully evaluated. The aim of this study was to assess outcomes of left-sided infective endocarditis in elderly patients and to determine the influence of surgery on mortality in the elderly. Methods and Results A nationwide retrospective study was performed of 2186 patients with left-sided infective endocarditis recorded in the SRIE (Swedish Registry of Infective Endocarditis), divided into patients aged <65 years (n=864), 65 to 79 years (n=806), and ≥80 years (n=516). Survival analysis was performed using the Swedish National Population Registry, and propensity score matching was applied to assess the effect of surgery on survival among patients of all ages. The rate of surgery decreased with increasing age, from 46% in the <65 group to 6% in the ≥80 group. In-hospital mortality was 3 times higher in the ≥80 group compared with the <65 group (23% versus 7%) and almost twice that of the 65 to 79 group (12%). In propensity-matched groups, the mortality rate was significantly lower between the ages of 55 and 82 years in patients who underwent surgery compared with patients who did not undergo surgery. Surgery was also associated with better long-term survival in matched patients who were ≥75 years (hazard ratio, 0.36; 95% CI, 0.24-0.54 [P<0.001]). Conclusions The proportion of elderly patients with infective endocarditis who underwent surgery was low compared with that of younger patients. Surgery was associated with lower mortality irrespective of age. In matched elderly patients, long-term mortality was higher in patients who did not undergo surgery, suggesting that surgery is underused in elderly patients.

Infective Endocarditis Due to Corynebacterium Species: Clinical Features and Antibiotic Resistance.

BACKGROUND: Corynebacterium species are often dismissed as contaminants in blood cultures, but they can also cause infective endocarditis (IE), which is a severe condition. Antibiotic resistance of corynebacteria is increasing making treatment challenging. Reports on IE caused by Corynebacterium species are scarce and more knowledge is needed. METHODS: Cases of IE caused by Corynebacterium species were identified through the Swedish Registry of Infective Endocarditis. Isolates were collected for species redetermination by matrix-assisted laser desorption ionization-time of flight and for antibiotic susceptibility testing using Etests. RESULTS: Thirty episodes of IE due to Corynebacterium species were identified between 2008 and 2017. The median age of patients was 71 years (interquartile range, 60-76) and 77% were male. Corynebacterium striatum (n = 11) was the most common IE causing pathogen followed by Corynebacterium jeikeium (n = 5). Surgery was performed in 50% and in-hospital mortality rate was 13%. Patients with IE caused by Corynebacterium species were significantly more likely to have prosthetic valve endocarditis (70%), compared with patients with IE due to Staphylococcus aureus or non-beta-hemolytic streptococci (14% and 26%, respectively) (P < .0001). Vancomycin was active towards all Corynebacterium isolates, whereas resistance towards penicillin G was common. CONCLUSIONS: Corynebacterium species cause IE, where prosthetic valves are mainly affected and surgery is often performed. Corynebacterium striatum is an important causative agent of IE within the genus. Antibiotic resistance of corynebacteria is relatively common but resistance towards vancomycin could not be detected in vitro.

Incidence of infective endocarditis caused by viridans group streptococci in Sweden - effect of cessation of antibiotic prophylaxis in dentistry for risk individuals.

INTRODUCTION: In October 2012, the Swedish Medical Products Agency published new recommendations for the cessation of prophylactic antibiotics in dentistry for the prevention of infective endocarditis (IE). Previously, 2 g of amoxicillin per os would be administered 1 h before invasive dental procedures to patients with valve prosthesis, complicated heart valve disease, and to those with previous endocarditis. OBJECTIVES: The aim of this study was to evaluate whether the total incidence of IE caused by oral viridans group streptococci (VGS) or IE caused by staphylococci, increased in Sweden after the introduction of the new recommendations. METHODS: The incidence of IE in Sweden before and after October 2012 was calculated and compared using an interrupted time series analysis. Separate analyses were conducted for the total incidence of IE, and IE caused by VGS or Staphylococcus aureus. Cases of IE were identified using the Swedish national registry of IE, which has existed since 1995 and contains data from all Swedish hospital clinics specialising in infectious disease. All cases with hospital admission date from the 1st of Jan 2008, to the 31st of Dec 2017 were included. The incidence calculations were corrected for annual changes in population size using data from the Swedish government agency Statistics Sweden. RESULTS: The results show no statistically significant increase in the slope of the trend line of the total incidence of IE, IE caused by VGS or S. aureus in the Swedish general population after October 2012, compared to before. CONCLUSION: The results suggest that the recommended cessation of prophylactic antibiotics for the prevention of IE in dentistry has not led to an increased incidence of IE caused by oral streptococci among the Swedish population.

Major cerebral events in Staphylococcus aureus infective endocarditis: is anticoagulant therapy safe?

OBJECTIVES: To study the impact of anticoagulation on major cerebral events in patients with left-sided Staphylococcus aureus infective endocarditis (IE). METHODS: A prospective cohort study; the use of anticoagulation and the relation to major cerebral events was evaluated separately at onset of admission and during hospitalization. RESULTS: Overall, 70 out of 175 patients (40%; 95% CI: 33-47%) experienced major cerebral events during the course of the disease, cerebral ischaemic stroke occured in 59 patients (34%; 95% CI: 27-41%), cerebral infection in 23 patients (14%; 95% CI: 9-19%), and cerebral haemorrhage in 5 patients (3%; 95% CI: 0.5-6%). Patients receiving anticoagulation were less likely to have experienced a major cerebral event at the time of admission (15%) compared with those without anticoagulation (37%, p = 0.009; adjusted OR: 0.27; 95% CI: 0.075-0.96; p = 0.04). In-hospital mortality was 23% (95% CI: 17-29%), and there was no significant difference between those with or without anticoagulation. CONCLUSIONS: We found no increased risk of cerebral haemorrhage in S. aureus IE patients receiving anticoagulation. Anticoagulation was associated with a reduced risk of cerebral events before initiation of antibiotics. Data support the continuance of anticoagulation in S. aureus IE patients when indicated.

One-year mortality in coagulase-negative Staphylococcus and Staphylococcus aureus infective endocarditis.

The aim of this study was to investigate in-hospital mortality and 12-month mortality in patients with coagulase-negative Staphylococcus (CoNS) compared to Staphylococcus aureus (S. aureus) infective endocarditis (IE). We used a prospective cohort study of 66 consecutive CoNS and 170 S. aureus IE patients, collected at 2 tertiary university hospitals in Copenhagen (Denmark) and at 1 tertiary university hospital in Gothenburg (Sweden). Median (range) C-reactive protein at admission was higher in patients with S. aureus IE (150 mg/l (1-521) vs 94 mg/l (6-303); p<0.001), which may suggest a more serous infection. CoNS was associated with prosthetic valve IE (49% vs 24%; p<0.001) and median diagnostic delay was longer in CoNS IE patients (20 d (0-232) vs 9 d (0-132); p<0.001). In-hospital mortality was equally high in both groups but 25% of the CoNS IE patients had died after 1 y compared to 39% of patients with S. aureus IE (p =0.05). In conclusion, CoNS IE was associated with a long diagnostic delay and high in-hospital mortality, whereas post-discharge prognosis was better in this group of patients compared to patients with IE due to S. aureus.