Culture-positive Infective Endocarditis Research Articles

Clinical profile of infective endocarditis: a single centre experience

Background: Infective endocarditis (IE) is an illness which still has a high rate of morbidity and mortality despite the availability of improved diagnostic and treatment amenities in the developing world. With an increasing number of children with congenital heart disease (CHD) undergoing corrective treatments, improved pediatric intensive care, better antimicrobial treatments, and a relative decrease in rheumatic heart disease (RHD) over the years, the epidemiology of pediatric IE in Bangladesh may be undergoing a change. The present study aims to describe the epidemiological, clinical, laboratory profile and outcome of IE among selected patients. Methods: This prospective cross-sectional study was conducted with a total of 35 patient of IE from January 2020 to December 2021, who were admitted in pediatric cardiology department, Bangladesh Shishu hospital and institute were enrolled in this study which was diagnosed according to modified Duke criteria. Results: There were 35 children diagnosed with IE during this period. The mean age at presentation was 84 months (range: 2-216 months). CHD (n=28/35, 80%) was the most common predisposing condition. A total of 20 % (7/35) patients had no preexisting structural heart disease. Staphylococcus aureus was the most common etiological agent. Blood culture positive IE was (n=18, 51.4%), blood culture-negative IE was (n=17, 48.6 %). Six patients (17.1%) died during the hospital stay. Conclusions: Increasingly younger children are being diagnosed with IE in Bangladesh and a significant number of them are in the setting of a structurally normal heart.

Evolving Patterns of Infective Endocarditis: Insights from a Tertiary Healthcare Institute in Western India

Abstract Context: Infective endocarditis (IE) is a dynamic disease with high morbidity and mortality despite advancements in diagnostics, antimicrobial therapy, and surgery. India faces a complex situation due to changing factors such as host characteristics, diagnostic techniques, antibiotics, and aggressive surgical approaches. Monitoring local epidemiology is crucial for prompt recognition and treatment. However, studies on IE trends in India are scarce and outdated. Aims: To investigate the clinical, microbiological, predisposing conditions, echocardiographic characteristics, and treatment outcomes of IE patients admitted to a Tertiary Care Academic Institute in Western India. Settings and Design: This retrospective observational study was done in a 2011-bedded tertiary care referral hospital in Western Maharashtra, between June 2019 and May 2023. The records of all adult patients (age >14 years) admitted during the study period with a definite diagnosis of IE, both native valve endocarditis and prosthetic valve endocarditis according to the modified Duke criteria, were included in the study. Baseline demographic data on age, sex, underlying heart disease, and predisposing conditions for bacteremia (infections, central venous catheters, surgeries, and invasive procedures) were collected. Subjects and Methods: The echocardiographic and microbiological findings, complications, treatment, and outcomes were noted. All blood cultures done for the diagnosis of IE were processed using standard methods to identify bacterial and fungal species and antimicrobial susceptibility profiles. For all the patients in this study, blood (5–8 mL per bottle) was collected in adult blood culture bottles using standard precautions and processed by a semiautomated blood culture system (BioMérieux, Marcyl̕ Etoile). Identification of causative organisms was performed by standard microbiological methods. Transthoracic and transesophageal echocardiography were performed to determine the location of vegetation, type of valve infected, and cardiac complications. Sample Size Calculation: Considering the Indian prevalence of IE to be 14.5% as observed by Gupta et al.,margin of error as 9%, and 95% of confidence level, the minimum required sample size calculated using WinPepi software (version: 11.65) for conducting the study was 59 patients. Statistical Analysis: Data was collected and entered into a database using Microsoft Excel. Data was represented as the frequency with percentage and Chi-square test (two-sample proportionality test) were applied for comparison of categorical variables. Quantitative data was summarized using mean and standard deviation and a two-sample t-test was applied to compare differences. P < 0.05 was considered statistically significant. Results: The mean age in the study was 44.1 ± 10.6 years with a female preponderance (male:female – 0.85:1). Rheumatic heart disease (RHD) (44.3%) was the most common underlying heart disease etiology, whereas 33% of patients did not have any cardiac disease. Blood culture was positive in 34.9% of episodes, with the most common organisms being Gram-positive Staphylococci (38%). Medical complications such as congestive heart failure (CHF) and acute kidney injury were seen in 41.2% of patients, followed by cerebrovascular accident and stroke in 20.6%. The majority of patients, 61.9%, had received antibiotics before referral to our center. Thirty-seven (58.7%) patients underwent definitive surgery for IE. The total in-hospital mortality rate was 12 (19.1%). In the univariate analysis, younger patients (<50 years) with CHF, diabetes mellitus, and Staphylococcus culture-positive IE were independent predictors of mortality. Conclusions: Over the past four decades, the landscape of IE in India has experienced noteworthy transformations. The disease profile of patients has shifted from predominantly older individuals with RHD to a rising number of younger patients with prosthetic valves or those without identified valvular conditions. Moreover, the yield of blood cultures has declined due to the increased utilization of antibiotics over the last two decades, although Staphylococcus species continue to be the most common organisms detected. Despite significant advancements in medical technology, the mortality rate remains unchanged. Our study provides compelling evidence to advocate for early surgical intervention, which holds the potential for improved outcomes.

1330. Pediatric infective endocarditis at a referral children’s hospital during 19-year period: Trends and Outcomes

Abstract Background We noted an increase in infective endocarditis (IE) cases in recent years. The purpose of the study was to examine the changes in incidence, risk factors, microbiology, complications and outcome of IE in our patient population. Methods Records of children < 18 yrs with discharge diagnosis of IE during 2002-2020 at Children’s Hospital of Michigan, Detroit were reviewed. Modified Duke criteria were used to determine “definite” and “possible” IE cases. Results 101 patients with IE were identified, representing annual incidence of 4.9/10,000 admissions. During 2002-2011 (early period), the incidence was 2.8/10,000 (33 cases). However, during 2012-2020 (late period), the incidence was 7.0/10,000 (68 cases): a 2.5-fold increase. Males were 53.4%. The age range was 1 mo – 17 yrs (median 6 yrs). Of 101 patients, 37 (36.6%) met criteria for definitive and 64 (63.4%) for possible IE. The most common predisposing conditions included congenital heart disease (CHD) (50.5%), central venous catheter (CVC) (25.7%), and immunosuppression (13.9%). CHD was more frequent in the late period (41/68, 60.3%) compared to early period (10/33, 30.3%) (p = 0.0059). Cardiac surgery had been performed in 28/51 (55%) prior to IE diagnosis. CVC related infections were more frequent in the early period (16/33, 48.5%) than the late period (10/68, 14.7%), (p = 0.0005). Overall, 16 (15.8) cases were culture negative. In culture-positive IE, S. aureus was most common (33/101, 32.7%) followed by streptococci (17), S. epidermidis (10), Gram negative bacilli (8), Enterococci (7), fungi (5) and HACEK group (4). Causative organisms were similar in both periods except for fungal organisms (5) and B. henselae (1) in the late period only. Valve replacement or valvuloplasty were performed in 19 (18.8%) patients. Complications included acute kidney injury (9) and emboli to brain (10) and to lungs (7). Mortality occurred in 15 (14.8%): 8 had CHD, 5 had CVC and 1 had fulminant MRSA infection. Conclusion Most of our IE patients had underlying medical conditions. The higher incidence of IE during the late period is likely due to an increase in the number of patients with complex cardiac conditions who underwent surgery at our institution. S. aureus was the predominant pathogen followed by streptococci. Mortality rate in our patients was 14.8%. Disclosures All Authors: No reported disclosures.

Outcomes of culture-negative vs. culture-positive infective endocarditis: the ESC-EORP EURO-ENDO registry.

AimFatality of infective endocarditis (IE) is high worldwide, and its diagnosis remains a challenge. The objective of the present study was to compare the clinical characteristics and outcomes of patients with culture-positive (CPIE) vs. culture-negative IE (CNIE).Methods and resultsThis was an ancillary analysis of the ESC-EORP EURO-ENDO registry. Overall, 3113 patients who were diagnosed with IE during the study period were included in the present study. Of these, 2590 (83.2%) had CPIE, whereas 523 (16.8%) had CNIE. As many as 1488 (48.1%) patients underwent cardiac surgery during the index hospitalization, 1259 (48.8%) with CPIE and 229 (44.5%) with CNIE. The CNIE was a predictor of 1-year mortality [hazard ratio (HR) 1.28, 95% confidence interval (CI) 1.04–1.56], whereas surgery was significantly associated with survival (HR 0.49, 95% CI 0.41–0.58). The 1-year mortality was significantly higher in CNIE than CPIE patients in the medical subgroup, but it was not significantly different in CNIE vs. CPIE patients who underwent surgery.ConclusionThe present analysis of the EURO-ENDO registry confirms a higher long-term mortality in patients with CNIE compared with patients with CPIE. This difference was present in patients receiving medical therapy alone and not in those who underwent surgery, with surgery being associated with reduced mortality. Additional efforts are required both to improve the aetiological diagnosis of IE and identify CNIE cases early before progressive disease potentially contraindicates surgery.

The clinical value of valve metagenomic next-generation sequencing when applied to the etiological diagnosis of infective endocarditis.

BackgroundMetagenomic next-generation sequencing (mNGS) is widely applied in the etiological diagnosis of infectious diseases. However, the clinical practice of mNGS in infective endocarditis (IE) is relatively less studied. This research aimed to assess the etiological diagnostic value of valve mNGS in IE.MethodsWe retrospectively analyzed 49 IE patients who underwent cardiac valve surgery in Zhongshan Hospital, Fudan University, Shanghai from 1 June 2018 to 30 November 2020. Among these IE patients, 28 were culture positive and 21 were culture negative. The culture results of the culture-positive IE patients were set as gold standard to assess the sensitivity and specificity of valve mNGS in the etiological diagnosis of IE. We studied the positive detection rate of pathogens by valve mNGS among the culture-negative IE patients. During the same period, we also collected the resected valves of 8 patients with non-infective valvular diseases for mNGS as negative controls.ResultsThe valve mNGS results of the culture-positive IE patients were the exact same as their culture results. Both the sensitivity and specificity of valve mNGS were 100%. The positive detection rate of pathogens by valve mNGS was 100% among the culture-negative IE patients. The stringent mapped reads number of genera (SMRNG), relative abundance of genera, stringent mapped reads number of species (SMRN), relative abundance of species, and coverage rate of valve mNGS results were significantly higher in culture-positive IE participants than in culture-negative IE participants. The valve mNGS results of the 8 participants with non-infective valvular diseases were all negative.ConclusionsValve mNGS is a promising technology for the etiological diagnosis of IE, especially culture-negative IE, and it may be used to guide precise antibiotic treatment after surgery.

Comparison of outcome between blood culture positive and negative infective endocarditis patients undergoing cardiac surgery

BackgroundUp to 30% or even more of all infective endocarditis (IE) cases are recognized as blood culture negative, meaning that the causative agent is left unidentified. The prompt diagnosis together with the identification of causative microorganism and targeted antibiotic treatment can significantly impact the prognosis of the disease and further patient’s health status. In some studies, blood culture negative endocarditis has been shown to be associated with delayed diagnosis, worse outcome and course of the disease, and a greater number of intra and postoperative complications.MethodsWe retrospectively analysed the medical records of all patients who underwent cardiac surgery for endocarditis between years 2016 and 2019. The aim of this study was to analyse short and long-term mortality and differences of laboratory, clinical and echocardiography parameters in patients with blood culture positive endocarditis (BCPE) and blood culture negative endocarditis (BCNE) and its possible impact on the clinical outcome.ResultsIn our study population were 114 (55.1%) blood culture positive and 93 (44.9%) blood culture negative cases of infectious endocarditis. The most common pathogens in the blood culture positive IE group were S.aureus in 36 cases (31.6%), Streptococcus spp. in 27 (23.7%), E.faecalis in 24 (21.1%), and other microorganisms in 27 (23.7%). Embolic events were seen in 60 patients (28.9%). In univariate analyses, detection of microorganism, elevated levels of procalcitonin were found to be significantly associated with intrahospital death, however it did not reach statistical significance in multivariate analyses. Among microorganisms, S.aureus was significantly associated with intrahospital death in both univariate and multivariate analyses.ConclusionsThere are no statistically significant differences between groups of BCPE and BCNE in terms of intrahospital mortality, hospital and ICU stay or 3-year mortality.There were higher levels of procalcitonin in BCPE group, however procalcitonin failed to show independent association with mortality in multivariate analysis.The most common microorganism in the BCPE group was S.aureus. It was associated with independently higher intrahospital mortality when compared to other causative microorganisms.

Culture-negative infective endocarditis (CNIE): impact on postoperative mortality.

IntroductionPoor postoperative outcomes have been reported after surgery for infective endocarditis (IE). Whether the absence of positive cultures impacts the prognosis remains a matter of discussion. The aim of this study was to evaluate the impact of negative cultures on the prognosis of surgically treated IE.MethodsThis was a single-center, retrospective study. From January 2000 to June 2019, all patients who underwent valvular surgery for IE were included in the study. The primary endpoint was early postoperative mortality. A covariate balancing propensity score was developed to minimize the differences between the culture-positive IE (CPIE) and culture-negative IE (CNIE) cohorts. Using the estimated propensity scores as weights, an inverse probability treatment weighting (IPTW) model was built to generate a weighted cohort. Then, to adjust for confounding related to CPIE and CNIE, a doubly robust method that combines regression model with IPTW by propensity score was adopted to estimate the causal effect of the exposure on the outcome.ResultsDuring the study period, 327 consecutive patients underwent valvular repair/replacement with the use of cardiopulmonary bypass and cardioplegic cardiac arrest for IE. Their mean age was 61.4 ± 15.4 years, and 246 were males (75.2%). Native valve IE and prosthetic valve IE accounted for 87.5% and 12.5% of cases, respectively. Aortic (182/327, 55.7%) and mitral valves (166/327, 50.8%) were mostly involved; 20.5% of isolated mitral valve diseases were repaired (22/107 patients). The tricuspid valve was involved in 10 patients (3.3%), and the pulmonary valve in 1 patient (<1%). Fifty-nine patients had multiple-valve disease (18.0%). Blood cultures were negative in 136/327 (41.6 %). A higher postoperative mortality was registered in CNIE than in CPIE patients (19% vs 9%, respectively, p = 0.01). The doubly robust analysis after IPTW by propensity score showed CNIE to be associated with early postoperative mortality (odds ratio 2.10; 95% CI, 1.04–4.26, p = 0.04).ConclusionsIn our cohort, CNIE was associated with a higher early postoperative mortality in surgically treated IE patients after dedicated adjustment for confounding. In this perspective, any effort to improve preoperative microbiological diagnosis, thus allowing targeted therapeutic initiatives, might lead to overall better postoperative outcomes in surgically treated IE.

Molecular detection of Coxiella burnetii in heart valve tissue from patients with culture-negative infective endocarditis.

Coxiella burnetii is a common cause of blood culture-negative infective endocarditis (IE). Molecular detection of C burnetii DNA in clinical specimens is a promising method of diagnosing Q fever endocarditis. Here, we examined the diagnostic utility of Q fever polymerase chain reaction (PCR) of formalin-fixed heart valve tissue from patients with blood culture-negative IE who underwent heart valve surgery. Clinical and laboratory data of patients with blood culture-negative IE who underwent heart valve surgery during a 6-year period and for whom biopsy tissues were available were reviewed retrospectively. Blood culture-positive IE patients who underwent heart valve surgery within the last 3 years were used as controls. Heart valve samples were cultured and also subjected to histological examination and PCR for Q fever, brucellosis, and bartonellosis. Data from 20 patients with blood culture-negative IE and 20 with blood culture-positive IE were analyzed. Eight cases of blood culture-negative IE were PCR-positive for C burnetii (40%; 95% confidence interval, 19-64). No specimen was PCR-positive for brucellosis or bartonellosis. Histologically, 4 of 8 specimens with a positive Q fever PCR result were characterized by clusters of multinucleated giant cells without a fibrin ring. None of 20 patients with blood culture-negative IE received anti-Coxiella antibiotic therapy due to lack of clinical suspicion. Six-month mortality was higher in the Q fever PCR-positive group than in the Q fever PCR-negative group [38% (3/8) vs 0% (0/12), P = .049). Of the 20 patients with blood culture-positive IE, none yielded a positive Q fever PCR result for valve tissue. Approximately 40% of patients with culture-negative IE who received heart valve surgery were PCR-positive for Q fever; patients without clinical suspicion suffered high mortality. These data suggest that Q fever IE in patients with culture-negative IE is often missed in routine clinical practice.

Healthcare associated infective endocarditis: A distinct entity

The terms hospital- and community-acquired infections do not cover any longer the full spectrum of acquisition of infection. Consequently, the term healthcare associated infection (HCA) has been recently introduced. In order to examine the applicability of 'HCA infection' to patients with infective endocarditis (IE), 125 episodes of culture-positive IE were categorized into 3 groups of acquisition. 14 (11%) of 125 episodes were defined as hospital acquired (HA) IE (onset of more than 72 h after admission), 52 (42%) as HCA (IE on admission in patients with significant previous healthcare contact), and 59 (47%) as community acquired (CA) (IE on admission in people without recent healthcare contact). 41 (77%) of the 53 causative agents in the HCA IE group were typical nosocomial pathogens, whereas these types of pathogens constituted only 22% (14/64) of the microorganisms in the group of CA IE (p<0.0001). Mortality in the HA and HCA groups combined was significantly higher than that in the CA group (19/62, 31%, vs 6/59, 10%, p=0.01). HCA IE should be recognized as a distinct category that constitutes a large proportion of all cases of IE. HCA IE is significantly different from CA IE and, therefore, may require a different therapeutic approach.