Treatment Of Infective Endocarditis Research Articles

Epidemiologic, clinical, and microbiologic profile of infective endocarditis in Argentina: A national survey. The Endocarditis Infecciosa en la República Argentina–2 (EIRA-2) Study

This study aimed to determine the epidemiologic, clinical, microbiologic characteristics, and inhospital outcome of infective endocarditis (IE) in Argentina and compare the results with those of the 1992 IE national survey. A prospective, multicenter study was conducted in 82 hospitals representing 16 of 24 provinces of Argentina. Patients with diagnosis of IE according to the Duke criteria were surveyed during an 18-month period. From 470 surveyed episodes of IE, 390 cases were classified as definite and 80 as possible IE. The mean age of the definite IE cases was 58.5 +/- 17.3 years; male sex, 70.0%; and male-female ratio, 2.3:1. Pathological evidence of IE was available in 26.2%. There was no previously known heart disease in 35.1%, and the proportion of prosthetic valve IE was 15.9%. Causative microorganisms were streptococci, 38.3% (Streptococcus viridans 27.0%, Streptococcus bovis 5.2%, others 6.1%); enterococci, 10.2%; staphylococci, 36.7% (Staphylococcus aureus 29.8%, coagulase-negative staphylococci 6.9%); HACEK group, 6.1%; fungal, 1.4%; and polymicrobial, 2.0%. Blood culture results were negative in 10.8%. Surgical treatment was performed in 26.2%, and the overall inhospital mortality was 24.6%. Patients from the 2002 survey were older (58.5 +/- 17.3 vs 51.3 +/- 18.7 years, P < .01) and more frequently had underlying heart disease (64.9% vs 55.0%, P < .01): degenerative valve disease (11.5% vs 4.8%, P < .01), congenital heart disease (9.5% vs 4.2%, P < .01), and prosthetic valve IE (15.9% vs 8.5%, P < .01). Conversely, the prevalence of rheumatic valve disease was significantly less than in the 1992 survey (5.4% vs 13.0%, P < .01). The EIRA-2 survey shows that the clinical profile of IE has changed in Argentina. Currently, patients with IE are older and have a higher frequency of underlying heart disease, degenerative valve disease, and prosthetic valve IE than previously. The incidence of staphylococcal IE has increased. Inhospital mortality remains high, suggesting that more aggressive measures are needed for the early identification, prevention, and treatment of IE.

Infective Endocarditis in Adolescents and Adults with Congenital Heart Disease

Background and Objectives:The development of new antibiotics and the advances in cardiac surgery has increased the number of patients with congenital heart disease (CHD) who grow into adulthood, and infective endocarditis (IE) has become one of the important complications. The aim of this study was to analyze the clinical findings of IE that occurred in adolescents and adults suffering with CHD. Subjects and Methods:In a retrospective case study, the medical records of 44 patients diagnosed as having IE were reviewed. The Duke criteria were used as the diagnostic criteria of IE. Results:Between October 1994 and December 2003, 44 patients and 49 cases were treated for IE with CHD in Samsung Medical Center. Their mean age was 45 years (median age: 44 years, range: 12-81 years) Ventricular septal defect (VSD) was the most common underlying cardiac disease (38.8%). In 18 of 49 cases (36.7%) CHD was diagnosed for the first time during the treatment of IE. 13 of the 31 patients with known CHD had not been seen on regular medical follow-ups. The common predisposing factors were dental procedures and acupuncture. The most common pathogens were Streptococcus viridans and Staphylococcus aureus. Valvular replacement was performed in 11 of the 19 VSD patients. Pulmonary complications developed in 12 (24.5%) and neurological complications developed in 10 (20.4%). The overall mortality was 2%. Conclusion: IE in adult CHD has become an important complication that infrequently accompanies a serious problem like severe valvular destruction or neurological complications. Proper management of CHD should be done early and educating the patient on the proper self-care for IE should be continued throughout life. (Korean Circulation J 2006;36:318-323)

Utility of serum C-reactive protein in assessing the outcome of infective endocarditis

To evaluate the diagnostic usefulness of serial serum C-reactive protein determinations in monitoring the outcome of infective endocarditis (IE). C-reactive protein, erythrocyte sedimentation rate (ESR), and white blood cell count (WBC) were measured from admission until week 10 in 129 patients with 134 episodes of IE. Need for cardiac surgery and final outcome were assessed until 3 months from admission. Data were evaluated using extensive statistical analyses. The fall in serum C-reactive protein or WBC was significantly faster when a patient had an uncomplicated recovery than when complications developed or death ensued, but no such behaviour was observed in ESR. None of the 80 patients who had normal C-reactive protein by week 10 died of IE. Moreover, none of the 22 patients who had normal C-reactive protein by week 4 needed cardiac surgery and only two of the 33 patients who had normal C-reactive protein by week 6 needed cardiac surgery, both after successful medical treatment of IE. Of the 87 patients whose WBC normalized within 4 weeks, six died and 15 needed valve surgery. The normalization of C-reactive protein proved to be a good predictor of a favourable late outcome (surgery, death) of IE. Also WBC count proved useful in the assessment of patients with IE, but the value of ESR was negligible.

PCR Detection of Bacteria on Cardiac Valves of Patients with Treated Bacterial Endocarditis

We used broad-range PCR amplification and sequencing to detect and identify bacterial DNA in 156 valves of patients treated for infective endocarditis (IE). Bacterial DNA was found more frequently in patients who underwent valve replacement while on antibiotic treatment for IE (60%) than in patients who had completed antibiotic treatment for IE (37%; P = 0.02). We found specific bacterial DNA in valves removed from 11 of 30 patients who had completed antibiotic treatment for IE. Six had no histological evidence of IE. The presence of DNA was significantly correlated with the presence of histologic lesions (P = 0.001) and with the presence of bacteria detected by Gram staining (P < 0.001). Bartonella and streptococci were detected for much longer after antibiotic treatment by PCR than other species (P = 0.047 and 0.04, respectively), and coagulase-negative staphylococci were detected for much shorter periods (P = 0.02). The finding that bacterial DNA was more likely to be detected in valves of patients with active IE than in patients who had completed antibiotic treatment for IE shows that bacterial DNA is cleared slowly. There was no significant correlation between the duration of antibiotic therapy and the presence of bacterial DNA in valves. Since the persistence of bacterial DNA in valves does not necessarily indicate the persistence of viable bacteria, the detection of bacterial DNA in valves from IE patients should be interpreted with caution, in particular in those patients with a past history of treated IE.

Infective endocarditis in Greece: a changing profile. Epidemiological, microbiological and therapeutic data

The epidemiology, and clinical and microbiological spectrum, of infective endocarditis (IE) in Greece was analysed in a prospective 4-year study in a tertiary hospital and a heart surgery centre in Athens. In total, 101 cases of IE (71 men, 30 women, aged 54.4 +/- 17.1 years) were studied, with a follow-up period of 3 months. Seventy-seven cases were definite and 24 possible; 59 involved native valves (native valve endocarditis; NVE), 31 prosthetic valves (prosthetic valve endocarditis; PVE), of which nine were early and 22 late, and 11 permanent pacemakers (pacemaker endocarditis; PME). There was a predominant involvement of aortic (48/101) and mitral (40/101) valves. Seven patients had rheumatic valvular disease, two had mitral valve prolapse, and eight had a previous history of IE. Thirteen and six patients had undergone dental and endoscopic procedures, respectively. In 13 patients, intravenous catheters were used within the 3 months before diagnosis of IE. There were three intravenous drug users among the patients. Staphylococcus aureus was the most important pathogen, isolated in 22% of cases, followed by viridans streptococci (19%) and coagulase-negative staphylococci (16%). Enterococcus spp. were responsible for 3%, HACEK group for 2%, and fungi for 6% of cases. Viridans streptococci were the leading cause of NVE (29%), Staphylococcus epidermidis of PVE (16%), and S. aureus of PME (54.5%). Six of 22 S. aureus and ten of 16 S. epidermidis isolates were methicillin-resistant. Surgical intervention, including total pacemaker removal, was performed in 51.5% of patients. Overall mortality was 16%, but was 29% with PVE, and was significantly higher with medical than with combined surgical and medical therapy (24.5% vs. 8%). Compared with previous studies, there were changing trends in the epidemiology, microbiology, treatment and prognosis of IE in Greece.

Combination Antibiotic Therapy for Infective Endocarditis

Despite the availability of new and potent antibiotics, modern echocardiography, and advanced surgical techniques, infective endocarditis (IE) is still associated with high morbidity and mortality rates. Use of synergistic antibiotic combinations is an appealing way to optimize therapy for IE. This review focuses on evidence-based recommendations for combination antimicrobial therapy for IE due to the most common etiologic pathogens. Few proven synergistic approaches for the treatment of IE have been globally demonstrated via in vitro models, experimental IE models, and human clinical trials, except for IE due to enterococci. Novel approaches, such as short-course aminoglycoside therapy and double-beta-lactam combination therapy, appear to be promising for treatment of enterococcal IE. Short-course combination therapy involving agents with activity against the cell wall (CWAs) and aminoglycosides is highly effective for IE caused by viridans group streptococci. Although synergistic combination therapy with CWAs-aminoglycosides remains widely used by clinicians for Staphylococcus aureus IE, few definitive human data exist that demonstrate the clinical benefit of such an approach.

Infective endocarditis in chronic haemodialysis: two treatment strategies.

Infective endocarditis (IE) is more frequent in patients on chronic haemodialysis (CHD) than in the general population and vascular access is the more frequent identified port of its entry. According to experimental and clinical studies the vascular access may also interfere with the treatment of IE. To improve the treatment of IE in CHD, patients were temporarily switched to peritoneal dialysis (PD) after the removal of the vascular access. In this preliminary report the outcome of IE in those CHD patients switched to PD is compared with the outcome in IE patients who remained on CHD. All cases of IE that occurred during a 5 year period were retrospectively analysed. The Duke criteria for IE were used for diagnosis. All patients underwent transoesophageal echocardiography. All patients were treated with the same schedule of antibiotic treatment. The vascular access of a patient was removed when it was judged to be the source of infection. Twenty-one patients were studied. Twelve patients had been temporarily switched to PD after the diagnosis of IE and nine patients had remained on CHD treatment. There were not statistically significant differences between the two groups with respect to demographic data, comorbid diseases and the frequency of Staphylococcus aureus as the causative germ. In-hospital mortality was 8.3% in patients switched to PD and 55.5% in patients maintained on HD (P: 0.03). The data presented here suggest that the high mortality of IE in CHD patients may also be associated with the vascular access necessary for HD. If these results are confirmed by prospective studies with higher numbers of patients, PD could turn out to have a place in the treatment of IE in CHD patients.

Early surgical intervention for infective endocarditis.

Infective endocarditis remains a serious and complex disease with significant morbidity and mortality. Sixty cases of infective endocarditis were retrospectively reviewed, consisting of 41 males and 19 females aged 7 to 50 years (mean, 30 years). Congenital heart disease was diagnosed in 19 of the patients and rheumatic heart disease in 41. Congestive heart failure occurred in 36 and systemic embolism in 8 cases. Blood cultures were positive in only 21.7% of the cases, while vegetations were detected by 2-dimensional echocardiography in 70%. Elective surgery was performed in 57 patients and emergent operation for systemic arterial embolization and/or intractable congestive heart failure in 3 patients. Two patients required reoperation for postoperative bleeding. All but 2 patients had been followed up for 6 to 160 months with no evidence of reinfection. Three patients with mechanical valve implantation later died of intracranial bleeding due to over-anticoagulation. The remaining 55 resumed normal activity. The encouraging outcomes were the result of an aggressive diagnostic approach and early surgical intervention.

CE Forum. Differential Diagnosis of Infective Endocarditis

Infective endocarditis (IE) is a deadly disease if left untreated. Early detection and treatment of IE reduces the high mortality rate. Mitral valve prolapse is now the leading risk factor for development of IE. The Duke (1994) criteria includes echocardiography as a diagnostic tool. Outclient i.v. therapy is increasing due to once-daily dosing regimens, which reduces the cost of treatment. Identifying at risk clients and educating them is vital to the prevention of IE. This article familiarizes the primary care provider with the pathophysiology, clinical presentation, diagnostic testing, complications, medical treatment, prophylactic management, and client education of IE.

Culture-negative endocarditis—causes, diagnosis and treatment

Infective endocarditis (IE) is associated with high morbidity and mortality. This infection is difficult to diagnose and, in some cases, to treat successfully particularly when the causative agent is non-culturable. Blood culture is still the most important laboratory test performed during the diagnostic work-up of IE. The bacteraemia associated with the disease is usually continuous and low grade. In two-thirds of all IE cases the blood cultures taken will be positive and will usually reveal a variety of aetiological agents depending on the patient population.Streptococcusspp. are the main causative agents in patients who have an intact immune system and possess native heart valves. Staphylococci are the predominant microorganisms in patients with prosthetic heart valves and in intravenous drug abusers. Other miscellaneous bacteria and fungi may also cause IE. However between 5 and 24% of suspected IE cases yield negative blood culture results; there are several possible explanations for this, including prior antibiotic therapy, fastidious and cell-dependent organisms or fungi. Ultimately the identification of the causative agent is the cornerstone of successful treatment of IE through appropriate chemotherapy. Conventional methodologies cannot detect the causative agent in culture-negative IE cases and hence difficulties arise in the clinical management of such patients. The aim of this review is to examine: (i) the reasons contributing to culture-negative IE; (ii) diagnostic criteria for the classification of IE; (iii) diagnostic methodology of IE, particularly trends in the application of molecular-based techniques; (iv) aetiological agents responsible for culture-negative IE; and (v) treatment of IE. © 2000 Lippincott Williams & Wilkins

Trends of childhood infective endocarditis in Israel with emphasis on children under 2 years of Age.

This study retrospectively analyzed the characteristics of infective endocarditis (IE) in children in light of recent advances in pediatric cardiology. We evaluated 25 consecutive patients with IE from 1980 to 1991 at a tertiary Children's Medical Center in Israel. The incidence of IE increased significantly over the second half of the study period, owing mainly to an increase in the number of patients less than 2 years old. Concomitantly, the causative microorganisms changed considerably, with a decrease in viridans streptococci, an increase in staphylococci and other uncommon causes of IE, and increased antibiotic resistance. Children under the age of 2 years, previously considered uncommon IE patients, accounted for 47% of the IE cases during the second half of the study period. The infection often (78%) appeared in children with complex congenital heart diseases, commonly after early palliative or definitive cardiac surgery. Infants who underwent systemic-to-pulmonary shunting, especially with implantation of foreign materials, were at highest risks. IE was more often hospital-acquired (56% versus 6%) and acute (56% versus 44%) in the younger children than in the older ones and often lacked the typical clinical presentation of the disease. In addition, uncommon causative organisms were noted more frequently (67% versus 13%; p = 0.009) in the younger group. The study shows a significant increase in IE in infants and young children with distinctive underlying conditions, clinical presentation, and microbiologic findings, all of which should be considered currently for the diagnosis and treatment of pediatric IE.

Infective endocarditis. Considerations for the timing of surgical intervention and type of infecting microorganism.

To determine the appropriate timing for surgical intervention in infective endocarditis (IE), we evaluated 24 patients (17 males, 6 females, with one included twice) who underwent surgical intervention for IE of native valves (NVE, n = 21) and prosthetic valves (PVE, n = 3) between January 1989 and September 1994. The mean age was 41 +/- 13 years (range 6 to 64 years). The most common infective organisms were Staphylococcus (33% of NVE) and Streptococcus (19% of NVE), with five NVE patients (24%) negative for blood culture. The PVE patients showed a different pattern of infecting organisms, with Enterococcus in one and Pseudomonas in another. From the resected valve culture and pathological findings, 12 patients were in the active stage at operation. Two in-hospital deaths occurred for a mortality rate of 8.7% (2/23). Further, surgical interventions were performed earlier with Staphylococcal infections than with Streptococcal infections, because hemodynamic compromise presented more progressively in the former. Also resected valve cultures and the pathological findings showed that a persistent infectious process existed in many cases of Staphylococcal infection in spite of intensive antibiotic therapy. In conclusion, we suggest that internists make referrals for surgical intervention for patients with NVE or PVE as early as possible in the active stage of infection.

Early surgery in infective endocarditis.

Optimal timing of surgical intervention in infective endocarditis is important in reducing mortality. We prospectively studied 126 consecutive episodes of infective endocarditis treated in one institution over 5 years, with special emphasis on long-term results and on the effects on outcome of surgical interventions. Twenty-six patients (21%) underwent acute surgery on median treatment day 14. Mortality during treatment was 8% for patients undergoing acute surgery vs. 11% for those not undergoing surgery, and the adjusted 5-year survival rate of acute surgically treated patients was 91%, compared with 69% for the medically treated patients. Using univariate analysis, excess mortality during 5 years follow-up was associated with new cardiac decompensation at entry (p < 0.01), age (p < 0.01), no acute surgery (p < 0.05) and mitral valve involvement (p < 0.05). Multivariate analysis showed new cardiac decompensation at entry to be an independent predictor of cardiac death at 5 years follow-up (relative risk 2.39; CI 1.05-5.45), while no surgery during active disease implied a relative risk of 3.45, though not statistically significant. Patients undergoing surgery very early (< or = 10 days of treatment) did not have a poorer outcome. Acute valve replacement, as compared with medical therapy only, might be important to increase both short-term and long-term survival in infective endocarditis.

Results of Surgical Treatment for Infective Endocarditis in Intravenous Drug Users

To determine the early and late results of surgical treatment for infective endocarditis (IE) in intravenous drug users (IVDU). Cohort study of consecutive IVDUs undergoing surgical treatment for IE. Large public hospital serving the urban population of Chicago, Ill. Consecutive IVDUs operated on between July 1982 and June 1991 for IE. Death, stroke, noncerebral systemic embolization, major bleeding, recurrent endocarditis, and repeated valve replacement. There were 80 patients, 58 men and 22 women, with a mean age of 37.5 +/- 10 (SD) years. The hospital course in all patients and follow-up data on 75 (94%) patients were complete. The primary indication for surgery was acute congestive heart failure in 44 (56%), persistent sepsis in 21 (26%), and multiple systemic embolization in 15 (19%) patients. Six patients (7.5%) died within 30 days of surgery. An additional 13 of 69 patients (17.6%) died during the follow-up, 8 from cardiovascular causes. The probability of survival at 36 months and at 60 months was 0.74 +/- 0.05 (SE) and 0.70 +/- 0.05, respectively. Seventeen (30%) of the survivors had at least one major cardiovascular event; 6 (8.8%) had recurrent endocarditis, 4 (5.8%) had stroke, 3 (4.4%) had extracerebral bleeding, 1 had extracerebral systemic embolism, and 3 (4.4%) required repeated valve replacement. Probability of event-free survival at 36 months and 60 months was 0.65 +/- 0.06 and 0.52 +/- 0.08, respectively. The median duration of event-free survival was 65 months. Since the expected mortality without surgery in patients with IE in whom medical treatment fails is almost 100%, it is concluded that surgical treatment is indicated for, and substantially improves the outlook for early and late survival of, IVDUs with IE who fail to respond to medical management.

Infective endocarditis causing acute myocardial infarction by compression of the proximal left coronary artery due to a mycotic aneurysm of the sinus of valsalva.

An extremely unusual case of myocardial infarction associated with infective endocarditis (IE) is described. A 38-year old male with a high fever was transferred to our hospital for further treatment of IE. Two-dimensional echocardiogram showed a large mycotic aneurysm of the sinus of Valsalva in contact with neighbouring structures. The patient had a rapid recovery within several days after administration of antibiotic agents. However, he then developed abrupt onset of severe precordial pain. From the echocardiogram images and biochemical evaluation he was diagnosed as having an acute subendocardial infarction. Serial echocardiograms revealed expansion of the aneurysm, extending from the myocardium of the anterolateral free wall to the lower margin of the proximal left coronary artery. The cause of acute myocardial infarction was thought to be incomplete occlusion of the coronary artery through compression by the enlarging mycotic aneurysm of the sinus of Valsalva. Urgent surgery confirmed compression of the left coronary artery by the large mycotic aneurysm as the cause of acute myocardial infarction.

Echocardiographic detection and clinical significance of left atrial vegetations in active infective endocarditis

Involvement of the mural endocardium during infective endocarditis (IE) was commonly reported in early series of patients, 1,2 but little new information has been added since antibiotic therapy dramatically reduced the mortality of this condition. Mural vegetations are thought to develop in 2 ways. The more common involves growth of a vegetation at the site of a “jet lesion,” that is, the impact site of a regurgitant stream. Much less common is isolated, primary mural endocarditis—through 1978 there had been only 22 reported cases. 3 Two-dimensional echocardiography can detect vegetations of IE in 43 to 100% of patients. 4 Some investigators have suggested that the detection of vegetations by echocardiography may identify a subgroup of patients at higher risk for embolic complications. 4–6 Others have included it as a minor criterion for surgical intervention in active IE. 7 Mural vegetations have not been well characterized echocardiographically, nor has their clinical significance been studied in detail. We report 6 patients with IE and left atrial (LA) masses demonstrated by 2-dimensional echocardiography. Doppler color flow imaging revealed a regurgitant stream striking endocardium at the base of the vegetation in all patients. Transesophageal echocardiography proved an excellent technique to study the location and size of vegetations attached to the posterior LA wall, which is difficult to visualize by standard 2-dimensional echocardiography.

FEVER DURING TREATMENT OF INFECTIVE ENDOCARDITIS

In 83 episodes of culture-positive infective endocarditis (IE) of a native valve, fever persisted or recurred in 42 (50%) despite appropriate bactericidal antibiotics. The commonest cause of fever was extensive infection of the valve ring and adjacent structures, even when the infecting organisms were viridans streptococci; urgent surgery was required. Less frequent causes were systemic and pulmonary emboli and drug hypersensitivity. Infected intravenous access sites were seldom responsible. In no case was fever due to antibiotic resistance of the infecting organism. In patients with a definite microbiological diagnosis who have been given appropriate antibiotics, the temptation to alter antibiotic therapy because of persistent or recurrent fever should be resisted unless there are features of drug hypersensitivity. When fever persists or recurs during treatment of IE, the opinions of a cardiologist and cardiac surgeon should be obtained as soon as possible; delay in valve replacement may prove fatal in patients with extensive infection.

Home treatment of infective endocarditis with oral amoxicillin

The seriousness of infective endocarditis (IE) has discouraged experimental clinical trials of varying regimens, but occasionally a clincal setting occurs that requires some compromise with the published standards for treatment. Most regimens of treatment of IE require 4 to 6 weeks of parenteral antibiotic therapy, and most routines recommend at least 2 weeks of intravenous treatment. The major exception is penicillin-sensitive streptococcal IE, for which a 4-week course of penicillin may be shortened to 2 weeks by the addition of streptomycin. 1 Gray 2 stands almost alone in recommending simply oral amoxicillin, although he has treated more than 90 patients with as high a success rate as can be claimed for any regimen for IE. We were recently confronted with a clinical situation in which an oral regimen at home was the only acceptable choice.

Is renal involvement a prognostic parameter in patients with infective endocarditis?

Renal involvement (RI)--defined as proteinuria greater than 150 mg per 24 h with haematuria or impaired glomerular filtration rate--was studied in 80 patients with infective endocarditis (IE). Proteinuria was measured quantitatively and further differentiated by the SDS-polyacrylamide-gel electrophoresis. RI was found in 40 patients (50%) with proteinuria from 150 to 8000 mg per 24 h. SDS-PAGE revealed a tubular protein pattern in 17 patients, a glomerular pattern in 6 and a glomerulo-tubular pattern in 17. Mortality rate was significantly higher in patients with RI (40%) than in those without (7.5%), and was not related to the type of infected valve, infective organisms, method of treatment (surgical or medical) or embolic events. Following successful treatment of IE, 18 out of 23 patients showed complete normalization of renal function. Renal involvement in patients with IE may be of prognostic significance--indicating an impaired prognosis.

Infective endocarditis in infants and children during the past 10 years: A decade of change

Infective endocarditis (IE) is closely associated with congenital heart diseases. 1–9 In major series done over several decades up to the early 1970s 2,6 and in a recent review 8 both the changing pattern of etiologic agents and the increasing incidence of IE overal has been stressed. In the last decade, the practice of pediatric cardiology has changed greatly. New diagnostic methods such as M-mode and two-dimensional echocardiography (2DE) have been developed. The rate of survival, particularly that of infants and of children with complex heart diseases, has greatly increased, coincident with improved surgery and intensive care of severely ill infants and children. Advances have also occurred in the antibiotic armamentarium. With these multiple recent developments it was questioned whether a change might have also taken place in the pattern of IE. Few reviews, however, dealing with the pattern of pediatric IE over the last decade are available. 8–10 This report is a review of our experience in diagnosis and treatment of pediatric IE during the last decade (1972 to 1982).