Infective Endocarditis in Patients With a History of Intravenous Drug Abuse

Infective endocarditis (IE) in people who inject drugs (PWID) has emerged as a growing public health concern. It entails two main issues future medicine will have to face: an increase in patients with substance abuse and the evolution of new microbial threats. The analysis of characteristics of the disease in this group of patients enables us to draw differentiating points. IE in PWID predominantly involves the right side of the heart, mainly the tricuspid valve. The prevalence of the disease is high in developed countries, in regions with a strong impact of drug abuse, particularly in the younger part of populations facing socioeconomic difficulties linked to changing life conditions in postindustrial economic systems. Staphylococcus aureus is by far the most frequent pathogen responsible for the infection in these patients, proportionally outnumbering the prevalence of this species in non-drug users. Also, higher rates of Gram-negative and fungal infections are posing a serious challenge in the treatment process. The Duke Criteria remain the common diagnostic methodology in all cases of IE, with echocardiography - both transthoracic echocardiography (TTE) and transoesophageal echocardiography (TEE) - being staples for imaging. The identification of the pathogen includes both standard microbiologic blood culture tests and the use of advanced biomolecular methods. Management in an optimal therapeutic process requires targeted antimicrobial therapy, which in many cases has to be supported by invasive surgical or percutaneous interventions. The widening spectrum of surgical procedures, such as percutaneous vegetation debulking, transcatheter valve-in-valve implantation, or minimally invasive cardiac surgery, represents a positive change for patients in poor clinical condition who are not suitable for standard cardiothoracic procedures.. While short-term survival seems promising at first, the long-term results are still dissatisfying. The main area for improvement is the need for a multidisciplinary approach that integrates infection management and prevention with addiction treatment. An innovative approach combining these factors could lead to a better prognosis in PWID with IE in the future.