Infective endocarditis at a tertiary care centre in Lebanon: predominance of streptococcal infection.

Objectives: Infective endocarditis (IE) remains a disease associated with high morbidity and mortality. Many epidemiological studies have been reported worldwide; however, data from the Middle East is scarce. Most studies have recently shown a trend towards increasing incidence of Staphylococcus aureus endocarditis and decreasing prevalence of rheumatic heart disease as a predisposing condition.

Methods: We conducted a retrospective review of all recorded cases of IE in adult patients admitted between 1986 and 2001 to the American University of Beirut-Medical Centre.

Results: The total number of cases was 91. The mean age was 48 years. Fifty-nine percent of patients had a predisposing cardiac condition, rheumatic heart disease being the most common (33%). Blood cultures were positive in 77.5% of the cases: the most commonly isolated organisms were Streptococcus spp. (51%; of which 57% were viridans streptococci.) and Staphylococcus spp. (36%; of which 72% were S. aureus and 28% were coagulase-negative staphylococci). Transoesophageal echocardiography was performed in 36 patients (40%), of which 32 (89%) showed positive findings. When applying the revised Duke criteria, 82% of the patients were classified as definite and 16.5% as possible endocarditis. Surgery was performed in 32% of cases mostly for valvular regurgitation, followed by heart failure. The complication rate was 69% with congestive heart failure, drug-related toxicities, new valvular regurgitation and systemic embolisation being the most common. The in-hospital mortality rate was 18%.

Conclusions: Unlike data reported from the United States and northern Europe, this study confirms that in Lebanon, a developing country, we continue to have a predominance of streptococci as aetiologic agents in IE, and rheumatic heart disease as the most common underlying heart condition. Application of the revised Duke criteria was useful in confirming the diagnosis of IE.