Recently, five North American studies have reported 471 persons who injected drugs intravenously (PWID) (25.34%) out of a total of 1858 patients with infective endocarditis (IE) and three European studies have reported 263 PWID out of 1225 patients with IE (21.46%). Both in North America and Europe the mean age of PWID with IE was 32-38 years and 41-44 years, respectively. Both in North America and in Europe Staphylococcus aureus was the leading cause of IE in PWID (67.30% and 66.15%, respectively). IE involves the tricuspid valve in 90% of cases and mitral and/or aortic valves in less than 15% of cases; the mortality rate is 2.0-2.5%. In North America and in Europe, streptococci caused IE in 10.61% and 10.64% of PWID, respectively, enterococci in 6.58% and 9.50%. Other etiologies accounted for 1-2%. Almost 6% of North American cases and almost 10% of European cases were polymicrobial. New episodes (25-32%) were mostly reinfections (up to 86.4%). PWID's in-hospital mortality was not significantly different from non-PWID's. Ten-year survival of PWID and non-PWID with IE was comparable in an American surgical study (69.5% vs 68.7%) and significantly different in a British study (43.8% vs 83.5%).