Infective endocarditis: a challenging disease

[Infective endocarditis: the role of surgery]

Infective endocarditis (IE) is a serious disease which can carry a bad prognosis if it is not appropriately treated. Sometimes the clinical evolution is unfavourable despite an optimal medical therapy with antibiotics. Surgery in these cases has an important role to eliminate the source of infection or to perform a valve replacement. The surprising evolution of patients operated in critic circumstances take us to analyze the role of early surgery. As physicians, we need to know these patients' risks and to establish the adequate surgical indications.

Infective endocarditis: a five-year experience at a tertiary care hospital in Pakistan

OBJECTIVES

Infective endocarditis is common and data regarding its pattern and outcome from developing countries is sparse. We therefore examined the spectrum, demographics and clinical features of infective endocarditis and sought to determine the factors affecting its clinical outcome.

PATIENTS AND METHODS

Over a five-year period at our university hospital in Karachi, Pakistan, we identified 66 patients with infective endocarditis and compared their clinicoepidemiologic features and outcomes to subjects in the West.

RESULTS

The male:female ratio was 2:1; overall median age was 24 years (35.5 years for men and 13.5 years for women) (p < 0.001). Median duration of symptoms before presentation was 20.5 days. Major predisposing cardiac abnormalities included congenital (50%) and rheumatic (23%) lesions, and a history of heart surgery (17%). Causative organisms and valvular sites of infection were similar to those seen in developed countries. Blood culture-negative infective endocarditis was found in 48% of cases. Renal failure was more frequent among culture-positive patients (p = 0.055). Risk factors for mortality included neurologic (p = 0.003) and embolic (p = 0.02) complications, renal (p = 0.03) and left ventricular failure (p = 0.002), and a history of cardiac surgery (p = 0.026). Overall mortality was 27%.

CONCLUSIONS

Patients with infective endocarditis in Pakistan exhibit significant differences compared to their counterparts in the West, including younger age at presentation, incidence of predisposing cardiac conditions, and gender differences reflecting sociocultural bias. Neurologic and embolic complications, renal failure and heart failure predict a worse outcome.

Central nervous system infections in injection drug users

Central nervous system infections in injection drug users are often devastating in terms of excess morbidity and mortality. In injection drug users with infective endocarditis, embolization from infected valvular vegetations may cause cerebral infarction, intracranial hemorrhage, and the formation of brain abscess. Focal intracranial infections (i.e., brain abscess and spinal epidural abscess) may occur in the absence of infective endocarditis, resulting from bacteremia that seeds the brain or epidural space. Antimicrobial therapy, combined with surgical intervention, may be essential to improve outcome from these neurologic complications. Toxin-mediated diseases (especially tetanus and wound botulism) are also seen in injection drug users. Inoculation of Clostridium spp at injection sites may lead to toxin generation and disease. Clinicians must maintain a high level of suspicion for these diagnoses in injection drug users.

Clinical, bacteriologic and echocardiographic evaluation of infective endocarditis in Ankara, Turkey

This study consists of a retrospective evaluation of microbiologic, echocardiographic, and clinical characteristics of patients with infective endocarditis seen at Türkiye Yüksek Ihtisas and SSK Ihtisas Hospitals during the previous 5 years to provide a basis for comparison with other series. The study was performed retrospectively. The mean age of the patient population, which consisted of 74 cases, was considerably low (24.6+/-12.3 yr). The majority of the patients were male (male/female = 1.96). Rheumatic valvular disease was the underlying cardiac pathosis in 66% of the cases. Congestive heart failure, embolic episodes, and mortality were more frequent among those with echocardiographically demonstrable cardiac vegetations. The microbiologic profile was considerably different from that of other series. In addition, this population showed a higher rate of congestive heart failure compared to other series. The patients with infective endocarditis in this series in the previous 5 years were found to be different from series reported from western countries.

A clinical consideration of systemic embolism complicated to infective endocarditis in Korea

OBJECTIVES

Infective endocarditis is still one of the important fatal diseases in Korea, especially when systemic embolisms are supervene. So, identification of patients who are in the high risk of embolism and who can be helped by early surgical intervention is very important. Considering these, we tried to elaborate the risk factors for the systemic embolism in patients with an infective endocarditis and the influence of systemic embolism on the mortality and morbidity in patients with an infective endocarditis.

METHODS

We retrospectively reviewed the clinical records of 97 patients who were admitted with the infective endocarditis between January 1983 and October 1993.

RESULTS

Among 97 patients, 80 patients met our diagnostic criteria. The mean age of patients was 38 years old. There were 43 males and 37 females. The mean duration of fever since the fever developed by history was 38 days. Valvular heart disease was the most frequent underlying heart disease. Mitral regurgitation and aortic regurgitation were the most common among valvular heart diseases. Pneumonia and acute pharyngotonsillitis were the most frequent predisposing factors of infective endocarditis. Blood cultures were positive in 51 patients (63.8%). Streptococcus viridans was the organism isolated most frequently, and Staphylococcus aureus was the second most frequently isolated one. Vegetations were detected in 58 patients (76.3%) by an echocardiography. Mitral valve and aortic valve were the most frequently involved incidence rate of embolism was 50% and the most frequent embolism site was the central nervous system and extremities were the next. Embolism occurred at the mean of 37 days after onset of fever. Overall in-hospital mortality rate was 26.3% and a cardiac-origin was the major cause of death. The only statistically significant risk factor for mortality was systemic embolism. The analysis of the relation between an incidence of embolism and the multivariables (age, presence of vegetation, location of vegetation, size of vegetation, causative organisms) showed that only the growth of Staphylococcus aureus had a significant trend toward a risk of subsequent systemic embolism.

CONCLUSION

This study suggests that systemic emboli increases the mortality rate in patients with infective endocarditis. Age of patients, presence of vegetation, size and location of vegetation are not the risk factors for embolism, while certain organism, especially Staphylococcus aureus, could be a risk factor for the systemic embolism.

Active infective endocarditis observed in an Indian hospital 1981-1991

Clinical data from 186 patients (133 males and 53 females) with 190 episodes of infective endocarditis (IE) occurring between January 1981 and July 1991 were studied retrospectively at a large referral hospital in Northern India with the intention of highlighting certain essential differences from those reported in the West. The mean age was much lower (25 +/- SD 12 years, range 2 to 75 years). Rheumatic heart disease was the most frequent underlying heart lesion accounting for 79 patients (42%). This was followed by congenital heart disease in 62 (33%) and normal valve endocarditis in 17 (9%). Twenty-four patients had either aortic regurgitation (n = 15) or mitral regurgitation (n = 9) of uncertain etiology. Prosthetic valve infection and mitral valve prolapse were present in only 2 patients each. A definite predisposing factor could be identified in only 28 patients (15%). Postabortal sepsis and sepsis related to childbirth accounted for 6 and 5 cases, respectively. Only 1 patient had history of intravenous drug abuse. Two-dimensional echocardiography showed vegetations in 121 patients (64%). Blood cultures were positive in only 87 (47%), with a total of 90 microbial isolates. Commonest infecting organisms were staphylococci (37 cases) and streptococci (34 cases). Except for a significantly higher number of patients with neurologic complications in the culture-negative group, there were no differences between patients with culture-positive and culture-negative IE. Of the 190 episodes of IE, the patients had received antibiotics before admission in 110 (58%) instances. A significantly greater number of culture-negative patients had received antibiotics than did culture-positive patients (87 vs 23, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Pyrexia of unknown origin: changing spectrum of diseases in two consecutive series

Comparison was made of the aetiology and methods of diagnosis in two series of patients meeting the classic criteria of pyrexia of unknown origin during 1968-1981 and during 1982-1989 seen in the Department of Internal Medicine at La Paz University Hospital, Madrid, Spain. There was a statistically significant decrease in the percentage of infections and an increase in neoplasms and connective tissue disorders in the second series. The percentage of patients diagnosed by laparatomy was similar in both series but the diagnosis yield at laparotomy was greater in the second period. Pyrexia of unknown origin continues to be a condition which can defy clinical expertise in in spite of advances in diagnostic techniques.

The changing pattern of infective endocarditis in childhood

Forty-eight cases of infective endocarditis (IE) that occurred in 42 patients with congenital heart disease were reviewed from 1970 through 1990 and were compared with a 20-year review of 108 cases diagnosed between 1953 and 1972. The review demonstrates that the natural history of IE in children has changed over the last 2 decades, with half of the cases occurring after surgery for congenital heart disease. In the postoperative group, 46% of patients had undergone valve replacement and 7 of these (29%) had a right ventricular to pulmonary artery valved conduit as the site for IE, suggesting significant additional risk in this setting. Among patients with nonsurgically treated congenital heart disease and IE, mitral valve prolapse has emerged as an important underlying heart lesion occurring in 29% of patients. The bacterial spectrum has shifted, with a significant increase in the incidence of uncommon causative organisms. Mortality has continued to decline with survivorship of 90% in this series.