MEDICAL EDUCATION CENTER, NOSRAT AVE, TOHID SQ., TEHRAN, IRAN
Background- The role of transthoracic echocardiography and the sensitivity rate of blood culture in the early diagnosis of infective endocarditis (IE) are not defined accurately in Iranian childhood population.
Methods- Thirty-six episodes of IE were evaluated in 36 children admitted to hospitals affiliated with Tehran University of Medical Sciences during a 5-year period (1996- 2000). The patients' major complaints, clinical findings, the medication they had been receiving and their tests and echocardiographic data were studied.
Results- The average age was 10.38±3.348 years. Overall, the male/female ratio was 2:1; fever was the most common complaint (100%). Sixty-six percent of the patients had fever more than 7 days. Congenital heart disease was the most common underlying disease (66%), followed by rheumatic heart disease (RHD, 22%). Congestive heart failure (CHF) was present in 30.5% of the cases. Blood cultures were positive in 42%, and vegetations were seen in 83.4% by 2-dimensional echocardiography (echo). Blood culture and echo sensitivity and specificity were 45 vs. 90.5 (p<0.00l) and 60 vs. 75 (p<0.05), respectively. The most common site of vegetation was the aortic valve area, followed by the tricuspid valve. Staphylococus aureus was the most common infecting microorganism. There were 6 deaths (16.6%) due to different causes. Indicators for mortality include negative cultures, infection with S. aureus, large vegetation and CHF. All mortalities had left-sided vegetations (p<0.05).
Conclusions- In contrast to the high sensitivity of blood cultures in IE in developed countries, in the developing countries the result of blood culture is not reliable.
Therefore, echocardiography can play a major role in the early diagnosis of IE and can change the outcome of this potentially serious illness.