Infective endocarditis in intravenous drug abusers: clinical challenges emerging from a single-centre experience

Abstract

Background Intravenous drug abuse (IDA) is a known risk factor for infective endocarditis (IE) and is associated with frequent relapses, but its prognostic impact is still debated. The potential futility of surgery in this population is a further issue under discussion. We aimed to describe the clinical characteristics, the therapeutic strategy, and the prognosis associated with IDA in IE. Methods We retrospectively analysed 440 patients admitted to a single surgical centre for definite active IE from January 2012 to December 2020. Results Patients reporting IDA (N = 54; 12.2%) were significantly younger (p < 0.001) and presented fewer comorbidities (p < 0.001). IDA was associated with a higher proportion of relapses (27.8 vs. 3.3%, p < 0.001) and, at multivariable analysis, was an independent predictor of long-term mortality (HR 2.3, 95%CI 1.1–4.7, p = 0.015). We did not register multiple relapses in non-IDA patients. Among IDA patients, we observed 1 relapse after discharge in 9 patients, 2 relapses in 5 patients and 3 relapses in 1 patient. In IDA patients, neither clinical and laboratory variables nor the occurrence of even multiple relapses emerged as indicators of an adverse risk–benefit ratio of surgery in patients with surgical indication. Conclusions IE secondary to IDA affects younger patients than those with IE not associated with IDA. Probably due to this difference, IE secondary to IDA is not associated with significantly higher mortality, whereas the negative, long-term prognostic impact of IDA emerges in multivariate analysis. Considering the good prognosis of patients with uncomplicated IE treated medically, surgery should be reserved to patients with a strict- guidelines-based indication. However, since there are no clear predictors of an unfavourable risk–benefit ratio of surgery in patients with surgical indication, all patients with a complicated IE should be operated, irrespective of a history of IDA.

Paravalvular Abscess Causing Severe Aortic Insufficiency with Aorto-Right Ventricular Fistula

“…IVDU is a widely recognized predisposing factor of IE, with an annual incidence of 1-5% in this population (4). It has been suggested that endothelial injury from injected particulate matter, direct injection of contaminated material, and drugassociated vasospasm leading to intimal damage and thrombus formation can lead to endocarditis with IVDU (5). Acquired aortic root to right ventricular communications are rare but can occur as stulisation from IE, as in our case.…”

Pneumonia, Arthritis, and Liver Injury: A Cardiac Diagnostic Conundrum

“…Compared to left-sided IE, right-sided IE is more commonly linked to intravenous drug use (IVDU), central venous catheters, and intracardiac devices, which have become more prevalent in recent years [ 6 ]. Right-sided IE accounts for 5-10% of all cases of IE, and IVDU is considered a strong risk factor for such an infection [ 6 - 7 ]. It is commonly observed that the tricuspid valve is most often affected in cases of endocarditis in IVDU, followed by the mitral and aortic valves [ 8 ].…”

“…A study conducted by Mathew et al has shown that among injection drug users, the pulmonary valve is involved in only a small number of cases [ 8 ]. IVDU increases the likelihood of introducing bacteria and other foreign organisms into the bloodstream, which can then infect the heart valves [ 7 ]. In addition, individuals who use IVDU may also have weakened immune systems, making them more susceptible to bacterial and fungal infections [ 7 ].…”

“…IVDU increases the likelihood of introducing bacteria and other foreign organisms into the bloodstream, which can then infect the heart valves [ 7 ]. In addition, individuals who use IVDU may also have weakened immune systems, making them more susceptible to bacterial and fungal infections [ 7 ]. Endocarditis has a wide range of symptoms, which can be nonspecific and difficult to diagnose [ 5 , 9 ].…”