Infective Endocarditis in People Who Inject Drugs: Report from the Italian Registry of Infective Endocarditis

Intravenous drug use is a predisposing condition for infective endocarditis (IE). We report the clinical features of IE, taken from the Italian Registry of IE, in people who inject drugs (PWIDs). The registry prospectively collected epidemiological, clinical, in-hospital, and follow-up data on patients with IE from 17 Italian centers. A total of 677 patients were enrolled, and 61 (9%) were intravenous drug users (IDUs). Most PWIDs were male (78.6%), and aged between 41 and 50 years old (50%). The most frequent comorbidities were HIV (34.4%) and chronic liver disease (32%). Predisposing factors for IE were present in 6.5% of the patients, and 10% had minor valvular abnormalities. IE had occurred previously in 16.4% of the patients, and 50% of them had undergone heart surgery. Overall mortality was 9.8% in IDUs and 20% in patients with recurrent IE. IE in PWIDs mostly affected the native valves (90%). The echocardiographic diagnosis of IE was based on the detection of vegetation in 91.82% of cases. Staphylococcus aureus was the main microorganism isolated (70%) from blood cultures. Thirty patients (49%) underwent heart surgery: thirteen had aortic valves, eleven had mitral valves, and six had tricuspid valve interventions. IE in PWIDs was relatively common, and patients with native valve right-sided IE had a better prognosis, with a low rate of surgical interventions.