Repeat Infective Endocarditis in Persons Who Inject Drugs: "Take Another Little Piece of my Heart"

Background. Injection drug use (IDU) is a major risk factor for infective endocarditis (IE). Few data exist on repeat IE (rIE) in persons who inject drugs (PWID). Methods. Patients >= 18 years old seen at Wake Forest Baptist Medical Center from 2004 to 2017 who met Duke criteria for IE and who self-reported IDU in the 3 months before admission were identified. The subset of PWID who developed rIE, defined as another episode of IE at least 10 weeks after diagnosis of the first episode, was then reviewed. Results. Of the 87 PWID who survived their first episode of IE, 22 (25.3%) experienced rIE and 77.3% had rIE within a year of the first episode. All patients who experienced rIE resumed IDU between episodes of IE. Of the patients with rIE, 54.5% had an infection caused by S. aureus and 22.7% required surgical intervention. Mortality at 1 year was 36.3%. Compared with their first IE episode, patients with rIE had fewer S. aureus infections (P =.01). Compared with PWID who experienced single-episode IE, intravenous prescription opioid use (P =.01), surgery (P <.01), tricuspid valve involvement (P =.02), and polymicrobial infection (P =.03) occurred more often during first episodes of IE in individuals who then developed rIE. Conclusions. rIE is common among IDU-related IE and confers a high 1-year mortality rate. The microbiology of rIE is varied, with S. aureus being less frequently isolated. More studies on modification of social and clinical risk factors are needed to prevent rIE.