Agents Of Infective Endocarditis Research Articles

Molecular diagnosis of infective endocarditis from culture-negative valve samples in a tertiary hospital in Iran.

The aim of this study was to investigate the prevalence of Tropheryma whipplei, Chlamydia psittaci, Chlamydia pneumoniae, Legionella, Brucella, and Francisella tularensis in valve samples from endocarditis patients using the real-time PCR method at a major referral heart hospital in Iran. In this study, 146 paraffin-embedded tissue samples from the heart valves of patients with clinical and pathological evidence of infective endocarditis (IE), who underwent heart valve replacement surgery between 2016 and 2020 at Tehran Heart Center were collected. After DNA extraction from paraffin-embedded valve tissue samples, they were surveyed for the presence of T. whipplei, C. psittaci, C. pneumoniae, Legionella, Brucella, and F. tularensis using quantitative real-time PCR (qPCR). The 16S rRNA gene sequence analysis was used for accurate species identification. Based on the molecular results, T. whipplei, Chlamydia spp., and Legionella spp. were detected in 10 (6.84%), 6 (4.1%), and 3 (2.05%) valve samples, respectively. In addition, one of six positive samples for Chlamydia spp. was identified as C. psittaci. No positive samples for F. tularensis and Brucella were found. In addition, all control valve samples were negative for all investigated pathogens. The findings suggest that specific bacterial species such as T. whipplei, Chlamydia spp., and Legionella spp. are associated with the development of IE. Considering the life-threatening nature of IE, it is critical for healthcare systems to prioritize the identification of its causative agents and develop targeted treatment strategies.IMPORTANCEInfective endocarditis (IE) is a serious and potentially life-threatening condition, and it is associated with significant morbidity, mortality, and complications, making it a major concern in both global and national healthcare systems. Late diagnosis and failure to receive appropriate treatment for patients with culture-negative endocarditis caused by hard-to-grow bacteria can lead to the death of patients. Unfortunately, in Iran, less attention is paid to the role of organisms that are difficult to cultivate in laboratory settings such as Tropheryma whipplei, Chlamydia psittaci, Chlamydia pneumoniae, Legionella, Brucella, and Francisella tularensis in causing culture-negative endocarditis, and these pathogens are overlooked by infectious, cardiologists, and health officials. This study underscores the need for special attention in the diagnosis of the agents of IE.

Epidemiological profile and mortality of infective endocarditis over the past decade: a systematic review and meta-analysis of 133 studies comprising 132,355 cases

Abstract Background Understanding the epidemiology of infective endocarditis (IE) is crucial in the context of an aging population, increased comorbidities, and the heightened occurrence of healthcare-associated cases. Comprehensive data on causative agents, affected valves, and associated mortality are essential for current clinical practice. Methods This systematic review was conducted according to the PRISMA guidelines. A random effects model meta-analysis was conducted. Eligible studies reporting outcomes on IE were identified through a search of the PubMed/Medline database from 2010 to 2021. Results One hundred-thirty-three studies with 132,584 patients from six continents were included in the analysis. The most common causative agents of IE were Staphylococci species in 36% of cases, followed by Streptococci species in 26% of cases and Enterococci species in 10% of cases. Of the studies providing further speciation, the predominant species was Staphylococcus aureus with an incidence of 29%, followed by Viridans Streptococcus with an incidence of 12%. We found an in-hospital/30-day mortality of 17% (CI: 16%-19%) from 109 studies worldwide. In the subgroup analysis, the highest mortality rates were observed in Latin America 33% (CI: 28%-38%) and Africa 25% (CI: 21%-30%), while the lowest mortality rates were reported in Oceania 13% (CI: 8%-19%), followed by North America 14% (CI: 11%-18%), Asia 15% (CI: 12%-18%), and Europe 17% (CI: 16%-19%). The aortic valve was affected in 46% of cases, followed by the mitral valve in 43%. Tricuspid valve IE and multivalvular IE were identified in 7% and 14% of the cases, respectively. Conclusion Our study highlights the shift in epidemiological profile of IE over the last decade with S. aureus identified as the most common causative microorganism of IE in almost one third of cases. IE remains a highly morbid and fatal condition with high mortality rates even in tertiary and high-expertise centers worldwide. While left-sided IE is by far more common, right-sided IE and multivalvular IE are not rare entities and should be considered early in the differential of patients presenting with suspected IE to decrease the risk of future complications.Global burden of infective endocarditis.

Analysis of Aetiological Agents in Infectious Endocarditis in the Central Military Emergency University Hospital "Dr. Carol Davila" Bucharest.

Infective endocarditis (IE) is a pathological condition caused by various microbial agents that can lead to severe complications affecting the heart. Accurate diagnosis is crucial for the effective management of patients with IE. Blood culture is the gold standard for identifying the primary infectious agents, which is a key factor in diagnosing IE using the modified Duke criteria. The main objective of this study was to investigate the distribution of the etiological agents of IE and the most common secondary diagnoses associated with it. A total of 152 patients aged 23-95 years with a diagnosis of IE and proven etiology (through blood cultures or serological tests) were included in this study. The most common etiological agent identified through blood tests was Enterococcus faecalis, which was detected in 39 patients (23.5%). Staphylococcus aureus was the second most common agent and was identified in 33 patients (19.9%), followed by Staphylococcus epidermidis, which was identified in 12 patients (13.1%). Nine patients (5.8%) had high levels of anti-Coxiella burnetti IgG phase I and II antibodies. IE is a leading cause of death in the Department of Infectious Diseases. Early and accurate diagnosis, along with interdisciplinary treatment, can significantly increase the chances of patient survival. Currently, Enterococcus faecalis and Staphylococcus aureus are the dominant etiological agents of IE, highlighting the need to revise protocols for prophylaxis, diagnosis, and initial treatment of this condition.

Streptococcus sinensis Causing Tricuspid Endocarditis in a Child: An Unusual Pathogen at an Unusual Site: A Case Report with Review of Literature

Background: Infective endocarditis (IE) involving tricuspid valve is rarely reported in children. Common etiological organisms of IE include Staphylococci, viridans group Streptococci, and Enterococci. Other less frequent organisms include Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella (HACEK) group, and Candida, accounting for 1% of cases. We describe the rare case scenario of tricuspid valve endocarditis caused by an unusual pathogen. Clinical Description: An 8-year-old girl presented with complaints of cough, shortness of breath, and intermittent fever for the past 2 months. Since 10 days before presentation, the fever had become high grade, continuous, and associated with chills and rigors. As per parents, the child had incidentally been detected with some congenital heart disease (CHD) at 3 months of age, documents being unavailable, child remaining asymptomatic till this presentation, without any medications. On examination, the child was malnourished with pallor, Grade 3 clubbing, tachypnea, and tachycardia. Auscultation revealed bilateral basal crepitations and a pansystolic murmur of Grade 4 in tricuspid area. Management and Outcome: Along with routine investigations, a two-dimensional echocardiography was done which revealed perimembranous ventricular septal defect with left-to-right shunt, tricuspid valve vegetations with anterior tricuspid leaflet prolapse with ruptured chordea, severe tricuspid regurgitation, and thickened aortic valve with good biventricular function. Blood culture showed growth of Streptococcus sinensis. The child was treated with oxygen, diuretics, and intravenous ciprofloxacin and gentamicin according to antibiotic sensitivity pattern. The child became hemodynamically stable and symptomatically improved after 3 weeks of treatment. Conclusion: This case creates awareness regarding an usual pathogen – S. sinensis as an etiological agent of IE, involving an unusual site – the tricuspid valve, in a child with CHD.

Impact of Hemoglobin Level, White Blood Cell Count, Renal Dysfunction, and Staphylococcus as the Causative Organism on Prediction of In-Hospital Mortality from Infective Endocarditis.

Infective endocarditis (IE) is a highly fatal disease in cases of delayed diagnosis and treatment, although its incidence is low. However, there have been few single-center studies in which the risk of in-hospital death from IE was stratified according to laboratory findings on admission and the organism responsible for IE. In this study, a total of 162 patients who were admitted to our hospital during the period from 2009 to 2021, who were suspected of having IE according to the modified Duke classification, and for whom IE was confirmed by transesophageal echocardiography were retrospectively analyzed. Patients were observed for a mean-period of 43.7 days with the primary endpoint being in-hospital death. The in-hospital death group had a lower level of hemoglobin (Hb), higher white blood cell (WBC) count, lower level of estimated glomerular filtration rate (eGFR), and higher frequency of Staphylococcus being the causative agent than those in the non-in-hospital death group. In overall multivariate analysis, Hb, WBC count, eGFR, and Staphylococcus as the causative agent were identified to be significant prognostic determinants. IE patients with Hb < 10.6 g/dL, WBC count > 1.4 × 104/μL, eGFR < 28.1 mL/minute/1.7 m2, and Staphylococcus as the causative agent had significantly and synergistically increased in-hospital death rates compared to those in other IE patients. Low level of Hb, high WBC count, low eGFR, and Staphylococcus as the causative agent of IE were independent predictors of in-hospital mortality, suggesting that these 4 parameters may be combined to additively stratify the risk of in-hospital mortality.

Antibacterial copper-filled TiO2 coating of cardiovascular implants to prevent infective endocarditis-A pilot study.

Infective endocarditis (IE) poses a significant health risk, especially in patients with prosthetic heart valves. Despite advances in treatment, mortality rates remain high. This study aims to investigate the antibacterial properties of a copper titanium dioxide (4× Cu-TiO2) coating on cardiovascular implants against Staphylococcus aureus, a common causative agent of IE. Titanium oxide carriers functionalized with copper ions were employed as an antibacterial coating for heart and vascular prostheses. The coating's antibacterial efficacy was assessed using S. aureus ATCC 29213. Microscopic evaluations were conducted on both biological and artificial materials. Antibacterial activity was qualitatively assessed via a modified disc diffusion method and quantitatively measured through colony counts in NaCl suspensions. The coating process was successfully applied to all tested cardiovascular prosthetic materials. Qualitative assessments of antibacterial effectiveness revealed an absence of bacterial growth in the area directly beneath the coated valve. Quantitative evaluations showed a significant reduction in bacterial colonization on coated mechanical valves, with 2.95 × 104 CFU per valve, compared to 1.91 × 105 CFU in control valves. The 4× Cu-TiO2 coating demonstrated promising antibacterial properties against S. aureus, suggesting its potential as an effective strategy for reducing the risk of bacterial colonization of cardiovascular implants. Further studies are needed to assess the longevity of the coating and its efficacy against other pathogens.

Effect of Antibiotic Therapy on the Sensitivity of Etiological Diagnostic Methods in Patients with Infective Endocarditis after Surgery

Aim. Assessment of impact of the duration of preoperative antimicrobial therapy (AMT) on the sensitivity of microbiological examination and polymerase chain reaction (PCR) of blood/tissues of resected valves in operated patients with infective endocarditis (IE).Materials and methods. 52 operated patients with active IE were included prospectively (Duke criteria, 2015). All patients underwent microbiological examination of blood before admission to the cardiac surgery hospital, as well as parallel simultaneous microbiological examination and PCR of blood/tissues of excised valves, followed by Sanger sequencing. The duration of preoperative treatment was calculated from the first day of AMT according to IE diagnosis to the day of surgery.Results. The causative agent of IE was established in 84.6% (n=44) patients by means of complex etiological diagnosis. A significant decrease in the sensitivity of microbiological examination of venous blood was revealed when performed in the period before and after hospitalization to a surgical hospital (up 44.2% to 17.3%, p&lt;0.05). When comparing microbiological examination of blood/tissues of resected valves and PCR of blood/tissues of resected valves, molecular biological methods demonstrated the greatest sensitivity, with a great advantage when examining the tissues of resected valves (17.3% and 19.2% vs. 38.5% and 75.0%, respectively; p&lt;0.001). The microbiological examination of venous blood performed at an early date before admission to the cardiac surgery hospital was comparable in sensitivity to the PCR blood test performed at a later date after prolonged AMT, and significantly less sensitive in relation to the PCR of resected valve tissues [44.2% and 38.5% (p&gt;0.05) vs. 75.0% (p&lt;0.05)]. In course of AMT 1-28 days, there were comparable results of microbiological examination with PCR blood examination and significantly better results of PCR of resected valve tissues [31.0% and 34.5% and 41.4% (p&gt;0.05) vs 72.4% (p&lt;0.001), respectively], and with AMT ≥ 29 days, microbiological examination of any biological material was negative in all patients, and PCR of blood/tissues of resected valves retained high sensitivity (0% and 0% vs. 34.8% and 78.3%, respectively; p&lt;0.01).Conclusion. Long-term preoperative AMT significantly reduced the sensitivity of microbiological examination of resected valve blood/tissue in operated patients with IE, whereas PCR of resected valve blood/tissue was highly sensitive even with preoperative AMT for more than 29 days.

Etiological Structure of Infective Endocarditis in Certain Categories of Patients (Literature Review)

The review contains information about the most common pathogens of infective endocarditis (IE) in certain categories of patients. Basing on analysis of current national and foreign sources concerning IE study there are description of conditions favoring to dominance of various microorganisms in intravenous drug users, HIV-infected patients, patients on hemodialysis, with valve prostheses, diabetes mellitus and malignant neoplasm patients, elderly patients, and pregnant women.Distribution of both as typical for IE (staphylococci, streptococci, enterococci) and rare microorganisms as well polymicrobial endocarditis in mentioned above groups is considered. There is discussion about possible reasons of prevalence of methicillin-sensitive or methicillin-resistant Staphylococcus aureus species in different IE patient categories, disease development initiated by rare forms of microbial agents in immunosuppressive patients, microbial flora features depending on terms valvular infection after valve prosthetics. Despite on consideration about predominance of one or another microorganism as an etiologic agent of IE in given clinical situation, during medical help providing it should strive for precise verification of an etiologic factor for choice of effective antibacterial treatment.

Infective Endocarditis Caused by Multi-Drug Resistant Corynebacterium Species: A Case Report

Corynebacteria species are anaerobic, facultative, non-sporing, gram-positive bacilli that can cause infective endocarditis. In recent years, non-diphtherial Corynebacterium (diphtheroids) has increasingly been recognised as a cause of both localised and systemic infections. Determining the exact species of Corynebacteria is challenging due to their similar characteristics. Infective Endocarditis (IE) caused by Corynebacteria species is uncommon because positive blood cultures might be considered contaminants, leading to missed diagnoses. However, they can indeed cause IE, which is a severe condition. Antibiotic resistance among Corynebacteria species is common and has been increasing, making treatment challenging. In-vitro resistance to vancomycin cannot be detected reliably. Literature on IE caused by Corynebacteria species is limited, and more comprehensive information is needed. In cases of IE caused by Corynebacteria species, prosthetic valves are mainly affected, especially in elderly patients, and surgery is often required. Within the Corynebacterium genus, Corynebacterium striatum is a major causative agent of IE. Although Corynebacteria species in blood cultures are often considered contaminants from skin flora, they can also cause invasive infections such as sepsis and IE. The present case report describes the isolation of Corynebacteria species from the blood specimen of a 50-year-old male who presented with fever, headache, decreased appetite, and fatigue.

Nanotechnology in interventional cardiology: A state-of-the-art review

Despite the contemporary techniques and devices available for invasive cardiology procedures, the current diagnostic, and interventional modalities have many shortcomings. As a contemporary cross-disciplinary technique, nanotechnology has demonstrated great potential in interventional cardiology practice. It has a pivotal role in detecting sensitive cardiac biomarkers, nanoparticle-enhanced gadolinium (Gd) contrast to enhance the detection of atherosclerotic cardiovascular disease (ASCVD), and multimodal imaging like including optical coherence tomography (OCT)/infrared luminescence (IR) for coronary plaque characterization. Furthermore, in invasive cardiology, the potential benefit is in miniaturized cardiac implantable electronic devices (CIEDs), including leadless pacemakers and piezoelectric nanogenerators to self-power symbiotic cardiac devices. Nanoparticles are ideal for therapeutic drug delivery systems for atherosclerotic plaque regression, regeneration of fibrotic cardiomyocytes, and disruption of bacterial biofilm to enhance and prolong the effects of antimicrobial agents in infective endocarditis (IE). In summary, nanotechnology-assisted therapies can overtake conventional invasive cardiology and expand the horizon of microtechnology in the diagnosis and treatment of CAD in the foreseeable future.

Streptococcus gordonii DL1 evades polymorphonuclear leukocyte-mediated killing via resistance to lysozyme.

Streptococcus gordonii is an etiological bacterial agent of infective endocarditis. Although the pathogenesis mechanisms are not well understood, the interaction between streptococci and phagocytes is considered important for the development of infective endocarditis. Previous studies show that some S. gordonii strains, including DL1, survive in polymorphonuclear leukocytes (PMNs), whereas other strains such as SK12 are sensitive to PMN-dependent killing. In this study, we assessed the differences between the sensitivity of S. gordonii DL1 and S. gordonii SK12 to PMN-dependent killing. S. gordonii DL1 showed a higher survival when treated with PMNs than SK12. Both S. gordonii DL1 and S. gordonii SK12 showed high resistance to low pH condition. Compared to S. gordonii SK12, S. gordonii DL1 was sensitive to hydrogen peroxide. However, the resistance of S. gordonii DL1 to the tested bactericidal agents, especially lysozyme, was higher than that of SK12. Furthermore, we performed a bactericidal assay by treating a mixture of S. gordonii DL1 and SK12 with PMNs. S. gordonii DL1 did not enhance the survival of S. gordonii SK12 exposed to PMNs. These results indicated that S. gordonii DL1 is resistant to bactericidal agents that degrade bacteria in phagolysosomes. In addition, there was no secretory factor involved in the resistance to bactericidal agents. The findings of this study may help develop treatments for infective endocarditis caused by S. gordonii.

683. Epidemiology and Microbiology of Infective Endocarditis: A Six Year Experience

BackgroundThe epidemiology and microbiology of infective endocarditis (IE) is not well studied in India. Studies from developed countries report a culture positivity of more than 90% in IE, while in India it has been lower (40–70%). Viridans Group Streptococci (VGS) are the commonest organism identified from previous Indian studies. The state of Kerala in India has better health indicators compared to the rest of India and it is likely that the epidemiology of IE in Kerala may be different. We therefore studied the epidemiology and microbiology of IE in patients admitted to a tertiary care hospital in Kerala over six years (2015 – 2020).MethodsAn electronic medical record search was conducted to identify patients who satisfied definite or possible IE criteria as per modified Duke criteria. Three sets of blood cultures were sent in BacT/Alert blood culture bottles for all suspected cases of IE. Blood culture was done using BacT-ALERT 3D automated microbial detection system (bioMérieux, France) and organisms were identified using VITEK-2 system. Transthoracic echocardiogram was done for all patients and a transoesophageal echocardiogram was done when indicated.Results70 patients satisfied the inclusion criteria. Majority (70.4%) were male; mean age was 50.7±16.3 years. 71% patients had underlying valvular heart disease. Diabetes mellitus (53.5%) was the most common comorbidity followed by chronic kidney disease (18.3%). Mitral valve was most commonly affected (53.5%) followed by the aortic valve (19.7%) and both valves were involved in 5.7%. Right sided valves were affected in 8.5%. Prosthetic valve endocarditis accounted for 10% of cases. No echocardiographic evidence of endocarditis was seen in 11.3%. Blood culture was positivity was 64.8%. Staphylococcus aureus (20%) was the most common organism isolated, followed by VGS (17.1%). 50% of the Staphylococcus aureus isolated were methicillin resistant. Among 57 patients in whom an outcome was recorded, mortality was 12.2%.Microbiology profile of infective endocarditis ConclusionStaphylococcus aureus has emerged as the most common etiological agent of IE in our study, in contrast to previous studies from India where VGS was predominant. The high prevalence of MRSA is of concern.Disclosures All Authors: No reported disclosures

Modern trends in identification of causative agents in infective endocarditis

Advances in the diagnosis and treatment of patients with infectious endocarditis are limited by the high frequency of cases with an unknown etiology and imperfection of microbiological (cultural) methods. To overcome these problems new approaches to the identification of infectious endocarditis pathogens were introduced, which allowed achieving certain positive results. However, it should be noted that despite the wide variety of diagnostic tools currently used, there is no ideal method for etiological laboratory diagnosis of infectious endocarditis. The article discusses the features and place of immunochemical, molecular biological (MALDI-TOF MS, real-time PCR, sequencing, in situ fluorescence hybridization, metagenomic methods, etc.), immunohistochemical methods, and their advantages and limitations.

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.MethodsCases 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.ResultsThirty 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.

Characteristics, management, and outcome of infective endocarditis in the Czech Republic: prospective data from the ESC EORP EURO-ENDO registry.

Data describing contemporary profile of infective endocarditis (IE) in the Czech Republic are lacking. The aim of this study was to describe the current profile and outcomes of IE patients. Prospectively collected data on consecutive patients admitted for IE diagnosis between April 2016 and March 2018 to 11 main tertiary care cardiac centers in the Czech Republic were used for this analysis. Among 208 patients, 88 patients (42.3 %) had native valve IE (NVIE), 56 patients (26.9 %) had prosthetic valve IE (PVIE), and 57 patients (27.4 %) had intracardiac device-related IE (CDRIE). The mean age was 61.66±15.54 years. Staphylococcus aureus was the most common etiological agent of IE (27.4 %), whereas Culture negative IE was present in 26.4 % patients. Surgery was performed during hospitalization in 112 (53.8 %) patients. In-hospital death occurred in 21.2 % patients, while 1-year mortality was 40.3 %. In patients, who had an indication for surgery, but the procedure was not performed, mortality was significantly higher (p=0.002). High proportion of culture negative IE and IE related to artificial intra-cardiac materials calls for action. Furthermore, we show that cardiac surgery should be more often contemplated, especially in the presence of risk factors as septic shock and congestive heart failure (Tab. 6, Fig. 1, Ref. 32).

Daptomycin-based aminoglycoside-sparing therapy for streptococcal endocarditis: a retrospective multicenter study

Streptococci still represent common etiologic agents of infective endocarditis (IE). Although renal failure is frequently reported as an aminoglycoside-associated adverse event, last international guidelines recommend a beta-lactam/gentamicin combination therapy. We retrospectively evaluated the use of daptomycin-based aminoglycoside-sparing combination therapy for the treatment of streptococcal IE in seven referral hospitals in Italy. Retrospective, multicenter, observational study. All patients with streptococcal IE admitted from 2016 to 2018 were enrolled. Mortality and incidence of acute kidney injury (AKI) were compared between Group A (standard of care, SoC) and Group B (daptomycin-based aminoglycoside-sparing combination therapy). Fifty-four patients were enrolled, 33 in Group A and 21 in Group B. Mortality was 2/33 (6%) in Group A and 0 in Group B (p = 0.681); AKI incidence was 8/33 (24%) in Group A and 0 in Group B (p = 0.04). Daptomycin-based aminoglycoside-sparing combination therapy appears to be promising for the treatment of streptococcal endocarditis because of similar efficacy compared with SoC and significantly reduced incidence of AKI.

Changes in the Etiology and Clinical Characteristics of Pediatric Infective Endocarditis in South Korea.

Changes in the epidemiology, clinical manifestations, and outcomes of infective endocarditis (IE) have been reported in recent years. This study was performed to analyze changing trends in the etiology of IE in children in South Korea. A retrospective study of children with IE was conducted from 2 hospitals in Korea from 2004 to 2019. IE was defined according to the Modified Duke criteria. We analyzed the etiology and clinical outcome of 96 cases and compared the etiology with that during 1987-1997, as described in a previous study. A total of 96 cases in 89 children satisfied the modified Duke criteria. The median age was 9.5 years. Preexisting structural heart diseases were identified in 81 cases (84.4%). Ten of the 15 cases with normal heart anatomy had a history of indwelling central venous catheters and underlying noncardiac conditions. Of the 72 identified organisms, common pathogens included Staphylococcus aureus, 24 (32.9%); viridans streptococci, 22 (30.2%); coagulase-negative staphylococci, 14 (19.2%); and Candida species, 7 (9.6). Sixty-three cases (66.7%) required surgical intervention, and the overall fatality rate was 7.9%. Compared with the period of 1987-1997, an increasing trend in the proportion of staphylococci as the etiology of IE in 2004-2019 was observed (26.7% vs. 51.8%, P = 0.029). In addition, S. aureus was associated with the high rate of developing complications (P < 0.05). In South Korea, Gram-positive cocci represent 85% of all etiologic agents of IE in children with an increasing trend in the proportion of staphylococci.

In vitro activity of ceftaroline and ceftobiprole against clinical isolates of Gram-positive bacteria from infective endocarditis: are these drugs potential options for the initial management of this disease?

The in vitro activity of ceftaroline and ceftobiprole was assessed against 77 Gram-positive bacterial isolates recovered from patients diagnosed with infective endocarditis (IE). Our data confirm that these drugs are highly in vitro active against the most common agents of IE including methicillin-resistant Staphylococcus aureus, methicillin-resistant coagulase-negative staphylococci, and Streptococcus spp., with no significant differences between them. Also, ceftaroline and ceftobiprole have demonstrated a good activity against Enterococcus faecalis (MIC90 0.75 μg/mL and 0.5 μg/mL, respectively). The spectrum of these drugs together with the in vitro and in vivo data on them related with IE published in the scientific literature places them as potential options for the initial management of this disease.

Clinical and morphological characteristics of infective endocarditis

The aim of the study was to identify the features of the clinical course and morphogenesis of infective endocarditis (IE) in HIVinfected injecting drug users with concomitant hepatitis C virus infection in comparison with the clinical and morphological picture of endocarditis in persons without drug dependence. It was found that the causative agent of IE in HIV-infected patients was staphylococcus aureus (71.8%), and in persons without drug dependence in the etiology of the disease the conditionally pathogenic flora prevailed. In HIV-infected drug-dependent patients, the tricuspid valve was affected (82.7%), and in persons without drug dependence — isolated aortic valve damage (40%) and combined mitral and aorticvalve lesions (36.4%). Purulent sepsis complications in drug-dependent patients with IE are less common than in patients without drug dependence due to immunosuppression, which is present in HIV-infected persons.

Characteristics of Species Composition of Causative Agents in Infective Endocarditis

&#x0D; Introduction. The frequency of infective endocarditis (IE) in children with congenital heart disease (CHD) is 15– 140 times higher than that in the overall population and varies from 2 to 18% according to different authors.&#x0D; The aim. To define the main groups of causative agents of infective endocarditis in children and adults in order to build up an antibiotic treatment algorithm.&#x0D; Materials and methods. The analysis of examination findings and treatment outcomes in 124 patients was conducted from 2014 to 2019. These patients received medical treatment at the Ukrainian Children`s Cardiac Center (UCCC), Kyiv. The patients were divided into two groups by age: group 1 included children aged from 6 days to 18 years (62 [50.0%]), group 2 comprised adults aged from 18 to 79 years (62 [50.0%]).&#x0D; Results and discussion. Forty-nine isolates were recovered from 124 patients during the analysis of microbiological study results. The frequency of bacterial IE causative agents was 26 (41.9%) in group 1, and 17 (27.4%) in group 2. Comparative analysis of the spectrum of IE pathogens revealed differences in the two study groups. Coagulase-negative staphylococcus was the most common causative agent in group 1 (46.7% of all isolated strains; n = 12) and in group 2 (44.4%; n = 8). Staphylococcus aureus in children was detected in 5 (8.1%) cases, whereas in adults only in 2 (11.1%) cases. Pathogens of the Enterococcus spp. family (E. faecalis) were recovered in both study groups: in 6.5% (n = 2) and 16.6% (n = 3) of the patients, respectively. Gram-negative flora was detected in 3 (9.7%) patients of group 1 and, in 2 (11.1%) patients of group 2. Fungal flora was more commonly found in children (7 [22.6%] cases represented by the Candida family), whereas in adults only 1 (5.6%) case represented by the Mucor family was revealed.&#x0D; Conclusions. Etiological structure of the infective endocarditis pathogens in both groups was represented mainly by gram-positive bacteria, with S. epidermidis (24.5%) being the most essential. The changes were revealed in the species composition of the pathogens in group 1 with fungal microflora dominance: Candida parapsilosis in 9.7%, C. albicans and C. famata in 6.5% of the total number of plated cultures in this group. The difference in surgical operations due to possible IE in both groups was established based on the specific features of operations determined by the age factor.