Aetiology and epidemiology of infective endocarditis in England and Wales.

Comparing data relating to the estimated incidence of infective endocarditis and deaths due to this condition highlights the changing age and sex patterns over the last 50 years. Using these data it is estimated that about 20 cases per million population per year can now be expected many of whom will be aged 65 years or more. About 20% of cases die. Viridans streptococci are responsible for almost half the cases of endocarditis, faecal streptococci for 11%, staphylococci for 20% and Coxiella burnetii for 2-3%. The laboratory data for 1976-85 showed that 86 of 821 (10.5%) patients with Staphylococcus aureus endocarditis had valve prostheses and 55 (6.7%) were iv-drug abusers. Of the patients with endocarditis due to coagulase-negative staphylococci 100 of 361 (27.7%) had prostheses.