Current clinical aspects of bacterial endocarditis in infancy, childhood, and adolescence

Infective endocarditis in congenital heart disease

Congenital heart disease (CHD) has become the leading risk factor for pediatric infective endocarditis (IE) in developed countries after the decline of rheumatic heart disease. Advances in catheter- and surgery-based cardiac interventions have rendered almost all types of CHD amenable to complete correction or at least palliation. Patient survival has increased, and a new patient population, referred to as adult CHD (ACHD) patients, has emerged. Implanted prosthetic material paves the way for cardiovascular device-related infections, but studies on the management of CHD-associated IE in the era of cardiovascular devices are scarce. The types of heart malformation (unrepaired, repaired, palliated) substantially differ in their lifetime risks for IE. Streptococci and staphylococci are the predominant pathogens. Right-sided IE is more frequently seen in patients with CHD. Relevant comorbidity caused by cardiac and extracardiac episode-related complications is high. Transesophageal echocardiography is recommended for more precise visualization of vegetations, especially in complex type of CHD in ACHD patients. Antimicrobial therapy and surgical management of IE remain challenging, but outcome of CHD-associated IE from the neonate to the adult is better than in other forms of IE.

CONCLUSION

Primary prevention of IE is vital and includes good dental health and skin hygiene; antibiotic prophylaxis is indicated only in high-risk patients undergoing oral mucosal procedures.

Successful treatment of infective endocarditis with recombinant tissue plasminogen activator

OBJECTIVES

In a prospective study, we examined the effect of treatment with recombinant tissue plasminogen activator (r-TPA) on survival and morbidity in a series of high-risk children with infectious endocarditis (IE) after prolonged treatment with indwelling catheters. We hypothesized that r-TPA is an adjunctive therapy for dissolution of infected thrombi in drug-resistant IE.

STUDY DESIGN

In the prospective 3-year study (1998-2001), we identified high-risk children with chronic illness and prolonged treatment with indwelling catheters who developed IE and overwhelming sepsis. Patients were allocated to receive r-TPA after persistent and enlarging intracardiac vegetations and failure to respond to conventional medical management. Complications associated with treatment, survival, and cardiac morbidity were observed.

RESULTS

Seven infants were treated prospectively with r-TPA. All infants responded promptly to treatment, with resolution of the intracardiac vegetations within 3 to 4 days of commencement and without any adverse complications. All patients survived without long-term cardiac morbidity.

CONCLUSION

Recombinant tissue plasminogen activator may offer a safe alternative to surgical intervention in the high-risk infant with IE.

[Prevention of infective endocarditis in the child. Current status and protocols]

Infective endocarditis remains a severe, potentially lethal disease, which justifies a rigorous prevention schedule. Children with cyanotic congenital heart disease, mitroaortic valvulopathies, prosthetic valve and uncorrected ventricular septal defect are the most susceptible. Dental care is the main cause of bacterial graft, followed by upper respiratory tract and cutaneous infections. Prevention is mainly based upon antibiotic prophylaxis but patient education and good dental hygiene are also important.

Spectrum of infective endocarditis during infancy and childhood: 20-year review

The medical records of the 29 patients under 18 years of age with infective endocarditis (IE) seen over a 20-year period by our department were reviewed to provide an overview of the spectrum of IE during infancy and childhood. None of the 29 patients had had previous cardiovascular surgery. The mean age at onset of IE was 7 years 2 months; 3 patients (10%) were under 2 years of age at onset. One patient during the early years died following 4 months of treatment with various antibiotics. Three patients underwent urgent surgery, and 17 patients with healed IE had elective surgery. All of the 20 patients who were operated on survived. The remaining 8 were followed with medical treatment alone. Positive blood cultures were obtained from 24 (83%) patients, and streptococci were still commonly found (38%). Ventricular septal defect (VSD) accounted for 66% of underlying heart diseases and rheumatic heart diseases for 14%. Vegetations were detected in 12 (67%) of 18 patients observed by echocardiography. Among these 12 patients, 1 with VSD underwent urgent tricuspid valve replacement and VSD closure because of worsening congestive heart failure due to progressive tricuspid regurgitation. Echocardiography identifies patients at high risk with IE, though the presence of a vegetation on echocardiography does not necessarily of itself dictate surgical intervention.

Endocarditis in neonatal intensive care unit

The clinical spectrum of infective endocarditis (IE) in infants is examined in four infants between 3 and 9 months of age. None of the patients had signs of IE; all four had an anatomically normal heart. Echocardiograms showed echo-dense vegetations in the left side of heart in three cases and in the right side in one. Three of the four patients recovered after the episode of endocarditis. Three of the four patients had necrotizing enterocolitis in the neonatal period. The important predisposing factor was the presence of indwelling central catheter for intravenous nutrition. Unlike previously reported cases, coagulase-negative Staphylococci and Enterococci were important causative organisms in this high-risk nursery population.

Pediatric infective endocarditis in the modern era

Sixty-two cases of endocarditis occurring in children between January 1977 and February 1992 were reviewed and compared with series from the 1970s and early 1980s. Changes in risk factors, pathogens, diagnostic modalities, and outcome were determined. Complex congenital heart disease (22 cases) and unrepaired ventricular septal defect (9 cases) were the most common underlying lesions. A total of 19 children with normal anatomy had endocarditis; 6 had community-acquired infection and 13 had hospital-acquired endocarditis (11 of these 13 children had central venous catheters in place, including 7 premature infants). Echocardiograms revealed vegetations in 25 of 49 patients; 24 of these patients had positive echocardiographic findings on the first study. Echocardiographic findings were most often negative in children with complex cyanotic heart disease. Staphylococcus aureus (39%) was the most common pathogen isolated and was associated with a higher incidence of central nervous system complications (p < 0.0015) and a greater need for surgical intervention (p = 0.01) than were other pathogens. Methicillin-resistant S. aureus (eight cases) and coagulase-negative staphylococci (three cases) emerged as important pathogens but were not associated with increased morbidity or mortality rates. Fungal endocarditis (six cases) had a 67% mortality rate. Overall the mortality rate was 11%. Endocarditis remained undiagnosed in seven seriously ill patients until postmortem examination. This study indicates that, during the past decade, important changes in risk factors, pathogens, and the susceptible population have altered the presentation and management of endocarditis in children.

Infective endocarditis in children: profile in a developing country

With the object of studying the profile of infective endocarditis in Indian children younger than 16 years of age, a retrospective study of 37 patients with infective endocarditis admitted to this hospital between January 1984 and December 1990 was carried out. There were 26 boys and 11 girls (aged 2-16 years (mean (SD) 10.3 (3.8)). Eighteen (48.6%) patients had underlying congenital heart disease, 13 (35.1%) had associated rheumatic heart disease whilst the remaining six had no pre-existing heart disease. All six patients with a normal heart and infective endocarditis had preceding extra-cardiac bacterial illnesses (epididymitis and orchitis in one, pneumonia in five). Blood cultures were positive in only 16 (43.2%): Staphylococcus aureus was grown in nine, Streptococcus viridans in six and Candida albicans in one. Sixteen (43.2%) of the 37 patients died owing to worsening cardiovascular haemodynamics, uncontrolled septicaemia and our inability to offer emergency surgery. The profile of infective endocarditis in developing countries is different from that in Europe and the United States of America, and the disease carries a very high mortality.

Bacterial endocarditis in children: trends in its diagnosis, course, and prognosis

In a population-based study of 41 children with bacterial endocarditis (BE), diagnosed in the period 1970 through 1989 in eastern Denmark, we analyzed trends in the diagnosis of BE and in mortality, and searched for possible prognostic factors. During this period the delay in diagnosis from first symptom to treatment did not change, but the delay from admission to treatment was significantly prolonged from 0 to 3 days, despite the introduction of echocardiography (ECHO). There was a significant improvement in the prognosis, the mortality rate having decreased from 40 to 0% [95% confidence limits: 12-74 vs. 0-26 (0.01 less than p less than 0.02)]. The improved prognosis was not explained by changes in the etiology or pattern of antibiotic resistance and may reflect a milder course of BE in children. Children with "mild anomalies"--such as bicuspid aortic valve (n = 5), coarctation of the aorta (n = 2), and prolapse of the mitral valve (n = 2)--had a significantly poorer prognosis than children with other forms of congenital heart disease (CHD) (p = 0.004), a reminder of the importance of suspecting BE in all children with unexplained long-lasting or intermittent fever, because some may have unrecognized "mild" CHD.

Infectious endocarditis in children

With the object of analyzing current characteristics of infectious endocarditis (IE) in children, we carried out a retrospective study of 23 cases of IE in children under 15 years of age seen at the Hospital Ramón y Cajal in Madrid (Spain) between 1977 and 1985. The incidence was high (1.3 cases per 1000 children admitted). The male/female ratio was 2:1. Eight patients were under 2 years of age and 15 over 2 years, the majority being adolescents. The two groups presented marked etiological and prognostic differences. Congenital heart disease was the predisposing factor in 20 of the 23 cases. Streptococcus viridans (nine cases) and Staphylococcus aureus (eight cases) were the most frequent organisms. Fourteen cases were on a native valve and nine were secondary (seven of these on prosthetic patches). In spite of advances in therapy, IE continues to be a severe illness: the mortality rate in our series was 26%. Factors associated with a poor prognosis were: age less than 2 years, Staphylococcus aureus as the causative agent, and the presence of prosthetic material.

Infective endocarditis in children: the changing profile

This article discusses the principles for diagnosis and treatment of infective endocarditis in children. There has generally been a consistent volume of streptococcus endocarditis, the major lesion in pediatric endocarditis, but there has been an increase in Staphylococcus aureus endocarditis as well as neonatal endocarditis. Neonatal endocarditis is a severe form of the disease.

Follow-up study on children with infective endocarditis

A follow-up study on 36 children having had infective endocarditis during the time period 1971-80 was performed. All answered a questionnaire and 33 underwent a complete non-invasive cardiac examination including exercise test. The study comprised 406 patient years. During this time there were four late deaths and three recurrent attacks of endocarditis. Seventeen (47%) took prophylactic antibiotics. Two patients had been operated on because of the initial infection and another five had developed intracardiac sequelae. An ability index given to each patient before the infection and at the follow-up showed that as a group these patients were doing well.

Infective endocarditis in Swedish children. I. Incidence, etiology, underlying factors and port of entry of infection

A retrospective study of Swedish children with infective endocarditis (IE) during the period 1971-80 was made. Sixty-six instances were identified in 64 children (0.39 cases per 100,000 children per year). Fifty (78%) had a previously known heart disease. Most commonly this was a ventricular septal defect and tetralogy of Fallot. Seventy-one percent had positive blood cultures. Streptococcus viridans and Staphylococcus aureus were most commonly isolated. Twenty-two percent of the children had undergone previous cardiac surgery. One case closely followed cardiac surgery and in only nine children could a definite port of entry of infection be demonstrated.

Infective endocarditis in Swedish children. II. Location, major complications, laboratory findings, delay of treatment, treatment and outcome

66 cases of infective endocarditis (IE) during 1971-1980 were studied. The infection was in most cases located to the mitral or aortic valve. Major complications were found in 43 children. In 17 children there was a long history of infection for which medical consultation had previously been sought prior to correct diagnosis. Antibiotics were administered to 60 children, in 58 intravenously while 2 received oral therapy only. Acute surgical intervention was necessary in six children and three of these children died. In all, 15 (23%) children died as a consequence of the infection.

Echocardiographic demonstration of free wall vegetative endocarditis complicated by a pulmonary embolism in a patient with ventricular septal defect

A defect in the muscular part of the interventricular septum in a 19 year old man was complicated by infective endocarditis caused by Staphylococcus aureus. The lesion was a large right ventricular free wall vegetation which embolised to the lungs. The vegetation was displayed by cross sectional echocardiography, which also confirmed the clinical diagnosis of ventricular septal defect. This case confirms the concept that the jet stream causes endocarditis at its point of impact. After six weeks' treatment with antibiotics the ventricular septal defect was repaired at operation.