Infective endocarditis: a review. I. Incidence, etiology, pathology and clinical features.

In this paper demographic characteristics, etiology, pathology and clinical features of infective endocarditis are reviewed simultaneous presentation of the data from our series of 50 cases with infective endocarditis. The peak incidence of infective endocarditis is between 11 and 15 years. Both sexes are equally affected. Patients with congenital or acquired heart disease tend to have hemodynamic trauma to the endocardium and vascular endothelium. These sites form the nidus for circulating bacteria of either spontaneous origin or the result of any oro-dental, genitourinary or other surgery or procedures and produce vegetations characteristic of infective endocarditis. The location of the vegetation is dependent upon the predisposing cardiac lesion. Embolic phenomenon is another cardinal feature of endocarditis and may occur in any organ system. Although a large variety of microbes have been known to cause endocarditis, streptococci and staphylococci remain the most frequent offenders. Clinical diagnosis of infective endocarditis is difficult because of the insidious onset and varied clinical features. A high degree of suspicion is essential for early diagnosis. Any patient with known heart disease and unexplained fever should be suspect for endocarditis. Splenomegaly, petechiae and embolic phenomena support this diagnosis. New or changing murmurs, splinter hemorrhages, Osler's nodes. Janeway's lesions and Roth's spots may be present. Elevated sedimentation rate, microscopic hematuria, leukocytosis with a shift-to-the-left and anemia may further support the diagnosis. Congenital or acquired heart disease and fever are all that will be present in many cases. Only isolation of the causative agent from the blood can confirm the diagnosis.