Recurrent Endocarditis in Persons Who Inject Drugs

Abstract

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.

Three Separate Clinical Entities of Infective Endocarditis—A Population-Based Study From Southern Finland 2013–2017

“…A relapse of IE was defined as an IE episode occurring within 6 months after the initial episode with the same causative agent. Re-infection was defined as an episode of IE occurring 6 months after a previous IE episode or as an IE episode within 6 months but not fulfilling the definition for relapse, consistent with a previous study [ 12 ]. Patients with pacemaker infection confined to a generator without any evidence of lead or endocardial involvement and those with aortic prosthetic infections without evidence of valve involvement were excluded.…”

High-Risk Infective Endocarditis in People Who Inject Drugs

“…7 Even at hospitals with research groups that have been exploring the epidemiology of PWID with infectious endocarditis for many years, the proportion of patients who receive appropriate evidence-based addiction treatment services continues to be suboptimal. 8 For example, Tan and colleagues 1 report patients in their cohort received a consultation for inpatient addiction treatment for only 156 infectious endocarditis episodes (37.1%) and referral to outpatient addiction treatment for only 151 (36.0%). It is clearly time to move beyond descriptions and to either implement the delivery of such services for as many PWID with infectious endocarditis as possible or, if resources are limited, to consider randomizing patients to such services.…”

Peripherally Inserted Central Catheter Line Misuse Among People Who Inject Drugs While on Therapy for Infective Endocarditis

“…2,3 Injection drug use contributes considerably to the development and recurrence of infective endocarditis, 4,5 resulting in recurrence rates between 5.6%-25.0%. 6 Despite the rising incidence of infective endocarditis among persons who inject drugs, there is limited literature that assesses the relationship between clinical predictors and disease recurrence. 6,7 Only two studies have been published that assessed recurrent infective endocarditis among persons who inject drugs.…”

“…6 Despite the rising incidence of infective endocarditis among persons who inject drugs, there is limited literature that assesses the relationship between clinical predictors and disease recurrence. 6,7 Only two studies have been published that assessed recurrent infective endocarditis among persons who inject drugs. 4,6 However, these studies failed to account for survival bias as patients who succumb to a first episode or to complications of addiction cannot have a recurrent episode.…”