Key Points Question In first-episode infective endocarditis in persons who inject drugs, what are the clinical differences between patients who receive surgery vs those who are medically treated, and which factors are associated with mortality? Findings In this case series of 370 first-episode cases of infective endocarditis, the main significant differences between persons who inject drugs who received surgery and those who did not were the site of infection and cardiac complications. Decreased mortality was associated with surgery and referral to addiction treatment services, while higher mortality was associated with left-sided and bilateral infections. Meaning In selected persons who inject drugs with first-episode endocarditis, surgical management and referral to addiction treatment were associated with reduced mortality.

IMPORTANCE People who inject drugs (PWID) who are being treated for infective endocarditis remain at risk of new bloodstream infections (BSIs) due to ongoing intravenous drug use (IVDU). OBJECTIVES To characterize new BSIs in PWID receiving treatment for infective endocarditis, to determine the clinical factors associated with their development, and to determine whether new BSIs and treatment setting are associated with mortality.

Background Infective endocarditis (IE) is increasing among persons who inject drugs (PWID) and has high morbidity and mortality. Recurrent IE in PWID is not well described. Methods This was a retrospective cohort study conducted between February 2007 and March 2016. It included adult inpatients (≥18) at any of 3 tertiary care centers in London, Ontario, with definite IE based on the Modified Duke's Criteria. The objectives were to characterize recurrent IE in PWID, identify risk factors for recurrent IE, identify the frequency of fungal endocarditis, and establish whether fungal infection was associated with higher mortality. Results Three hundred ninety patients had endocarditis, with 212/390 in PWID. Sixty-eight of 212 (32%) PWID had a second episode, with 28/212 (12%) having additional recurrences. Second-episode IE was more common in PWID (11/178 [6.2%] vs 68/212 [32.1%]; P < .001). Peripherally inserted central catheter (PICC) line abuse was associated with increased risk of recurrent endocarditis (odds ratio [OR], 1.97; 95% confidence interval [CI], 1.01–3.87; P = .04). In PWID, fungal IE was more common in second episodes than first episodes (1/212 [0.5%] vs 5/68 [7.4%]; P = .004). Additionally, fungal infections were associated with mortality in second-episode IE in PWID with an adjusted OR of 16.49 (95% CI, 1.12–243.17; P = .041). Despite recurrent infection, likely due to continued drug use, there was a low rate of referral to addiction treatment (14/68 [20.6%]). Conclusions PWID have a high risk of recurrent endocarditis, particularly in patients who abuse PICC lines. Fungal endocarditis is more common in second-episode endocarditis and is associated with increased mortality. Consideration of empiric antifungal therapy in PWID with IE history and suspected IE should be considered.

Background: The rising incidence of infective endocarditis (IE) among people who inject drugs (PWID) has been a major concern across North America. The coincident rise in IE and change of drug preference to hydromorphone controlled-release (CR) among our PWID population in London, Ontario intrigued us to study the details of injection practices leading to IE, which have not been well characterized in literature. Methods: A case-control study, using one-on-one interviews to understand risk factors and injection practices associated with IE among PWID was conducted. Eligible participants included those who had injected drugs within the last 3 months, were > 18 years old and either never had or were currently admitted for an IE episode. Cases were recruited from the tertiary care centers and controls without IE were recruited from outpatient clinics and addiction clinics in London, Ontario. Results: Thirty three cases (PWID IE+) and 102 controls (PWID but IE-) were interviewed. Multivariable logistic regressions showed that the odds of having IE were 4.65 times higher among females (95% CI 1.85, 12.28; p = 0.001) and 5.76 times higher among PWID who did not use clean injection equipment from the provincial distribution networks (95% CI 2.37, 14.91; p < 0.001). Injecting into multiple sites and heating hydromorphone-CR prior to injection were not found to be significantly associated with IE. Hydromorphone-CR was the most commonly injected drug in both groups (90.9% cases; 81.4% controls; p = 0.197). Discussion: Our study highlights the importance of distributing clean injection materials for IE prevention. Furthermore, our study showcases that females are at higher risk of IE, which is contrary to the reported literature. Gender differences in injection techniques, which may place women at higher risk of IE, require further study. We suspect that the very high prevalence of hydromorphone-CR use made our sample size too small to identify a significant association between its use and IE, which has been established in the literature.

Disseminated histoplasmosis is a life-threatening disease usually seen in immunocompromised patients living in endemic areas. We present an apparently immunocompetent patient with gastrointestinal histoplasmosis who was initially diagnosed as biopsy-proven Crohn’s disease. Following discontinuation of anti-inflammatory drugs and institution of antifungal therapy, his GI illness completely improved. Specific fungal staining should be routinely included in histopathologic assessment of tissue specimens diagnosed as Crohn’s disease.