Changing profile of infective endocarditis during 31-year time course in a tertiary care hospital

Abstract

Aim: Infective endocarditis (IE), infection of the endocardial surface of heart, may cause mortality up to 30% despite advancements in medical care. Epidemiology of IE and profile of causative organism has changed in the last years. We aimed to investigate the changing profile of IE over a 31-year period in a tertiary care hospital 
 Material and Method: Medical records of 290 patients treated with the diagnosis of IE between 1974 and 2005 were re-evaluated according to Modified Duke criteria. Forty seven cases were classified as rejected cases. 
 Results: Of the 243 patients 109 was female (44.8%) and 134 male (55.2%). The mean age of the patients was 38±16.4 years (Table). The mean age of the patients showed an increasing trend throughout the time (p< 0.001) ; it was 29 years between 1974- 1980 but increased to 54 years in 2001-2005 period. Rheumatic valvular disease (RVD) was the most frequent underlying heart disease (60%) but showed a declining trend especially in the last years. S. aureus was the most common pathogen in all the time periods (15.2%). Blood cultures were negative in 90 (43%) patients. But the percentage of blood culture negativitiy decreased significantly from 63% in 1981-1985 periods to 28% in 2001-2005 period. (p: 002). Mitral valve was the most common affected valve (52, 44%). Surgery was performed in 74 of the 243 cases (30.5%). In-hospital mortality rate was 30.6. Mortality rate was significantly lower in patients who underwent surgery compared to ones who did not (19.2% vs. 35.8%, p< 0.005). Mortality rate was also lower in patients with community acquired infection compared to ones with nosocomial infection (27% vs 45%). Embolic events, nosocomial infections and surgery were independent risk factors for mortality. 
 Conclusion: The mean age of IE population is increasing, RVD disesase is less commonly seen as an underlying heart and S. aureus is the most common pathogen. These findings are compatible with the reports from developed countries. Surgery displays a protective effect on the prognosis of IE