Infective Endocarditis and Intravenous Drug Users: Never Was and Never Will Be Taken Lightly PMC

Anticoagulation should be withheld in patients with cerebral emboli, because it increases the risk of hemorrhagic transformation. The decision to withhold anticoagulation in other patients should be based on the relative risks of hemorrhagic stroke and thromboembolism (4). Right-sided lesions typically produce septic pulmonary emboli, which may result in pulmonary infarction, pneumonia, or empyema.

Proposed Treatment Recommendations

Therefore, the body’s immune response system, including the infection-fighting white blood cells, can’t directly reach the valves through the bloodstream. If bacteria begins to grow on the valves (this occurs most often in people with already diseased heart valves), it is difficult to fight the infection, whether through the body’s own immune system or through medications that rely on the blood system for delivery. Infective endocarditis (IE) is a significant risk and complication in patients with a history of intravenous (IV) drug use (DU), and treatments are becoming more invasive as infections become more serious. IV drug use is an extremely addictive behavior and challenging behavior to address, and patients are at high risk of relapse to IV drug use even after successful IE treatment. Addressing the underlying cause with behavioral modification is essential to prevent behavior and subsequent infection recurrence. Treatments depend on a multidisciplinary approach to address the physiologic and underlying psychological conditions that lead to this type of infection.

• For treatment of other uncommon pathogens, please read references (7, 15, 17–20, 24).
• Levine et al. [7] have proposed that intrinsic differences in the endothelium of valves on the right and left sides of the heart may cause certain organisms to adhere to particular valves.
• Patients with staphylococcal endocarditis tend to respond more slowly.
• However, no single microbiological characteristic appears to specifically account for the increased frequency of right-side infection among IDUs.
• Instead, degenerative valve disease of the elderly, mitral valve prolapse and intravenous drug use (IDU) are becoming the leading causes (2, 3).

What are the Risk Factors for Intravenous Drug Abuse Endocarditis? (Predisposing Factors)

In addition, length of hospital stay was shortened in the patients switched to oral therapy. This approach has the potential to reduce the psychologic stress and some of the risks inherent to prolonged inpatient parenteral therapy (2). Blood cultures may require 3 to 4 weeks of incubation for certain organisms; however, some proprietary, automated culture monitoring systems can identify positive cultures within a week.

• Subsequent MSCRAMM-fibronectin-fibrinogen-extracellular matrix interactions would predispose right-side valves to colonization.
• It may present with a wide variety of clinical signs, some subtle; the diagnosis may be difficult or the signs misleading, and there is a wide differential diagnosis to consider.
• If the cause of IE is injection of illicit drugs or prolonged use of IV drugs, the tricuspid valve is most often affected.
• Among these, the tricuspid is the most common affected valve, although the mitral and/or aortic valves can also be involved.
• The choice of antibiotic and the length of treatment is based on the type of infection causing the endocarditis.
• Different intrinsic features of these common pathogens account for their virulence and prevalence (table 4).

Multidisciplinary Care Is Crucial

Although the pathogenesis of non-IDU-related endocarditis has been well-defined, there is no definitive explanation for the increased prevalence of right-side endocarditis among IDUs [14, 15]. In this article we explore these different proposed mechanisms for the increased prevalence of right-side endocarditis in IDUs. If, following blood cultures, the diagnosis is secure, high-dose IV antibiotics should be started immediately. It is becoming increasingly common to insert a tunneled central line to facilitate several weeks of IV treatment without the need for repeated cannulation – with the pain and attendant risk of secondary infection that this incurs.

Patient selection

A paper in the Journal of Cardiac Surgery presents the STOP score, a tool for predicting operative morbidity and mortality in individual patients with DUA-IE. Surgical intervention is indicated if the patient has refractory heart failure, persistent or recurrent infections including bacteria and fungi, prosthetic valves, development of a ring abscess, fistulae or worsening conduction abnormalities. However, special considerations are involved in the surgical treatment of IE in the population of IDU.

Deterrence and Patient Education

Aureus endocarditis (the remaining 26% had right-side valvular involvement). Since there were equal numbers of men and women in the addict and nonaddict groups, the presence of subclinical mitral prolapse as an explanation for left-side predilection is not applicable. If immediate antibiotic treatment is warranted, this can be initiated iv drug use right after completion of blood culturing, once microbiology tests have identified a specific organism and the antibiotic therapy has been modified accordingly. Antibiotic therapy can have an enormous impact on the patient’s prognosis; therefore, all efforts have to be made to collect and culture specimens as carefully as possible.

Prosthetic valve endocarditis