Table 1

Demographic and clinical characteristics of entire cohort

Stimulant use only (n=24)
n (%) or mean (SD)
Opioid use only (n=71)
n (%) or mean (SD)
Both stimulant and opioid use (n=166)
n (%) or mean (SD)
All injection drug use
(n=290)
n (%) or mean (SD)
Age at admissionMean (SD)38.2 (10.9)37.1 (9.8)33.7 (9.0)35.1 (9.8)
SexFemale12 (50)34 (48)90 (54)143 (49)
Male12 (50)37 (52)76 (46)147 (51)
HIV statusNegative17 (71)53 (75)117 (70)207 (71)
Positive1 (4.2)8 (11)20 (12)29 (10)
Unknown6 (25)10 (14)29 (17)54 (19)
Hepatitis C statusNegative5 (21)17 (24)24 (14)54 (19)
Positive16 (67)48 (68)128 (77)208 (72)
Unknown3 (12)6 (8.5)14 (8.4)28 (9.7)
HomelessNo20 (83)64 (90)132 (80)241 (83)
Yes4 (17)7 (9.9)34 (20)49 (17)
Site of IERight side11 (46)47 (66)114 (69)180 (62)
Left side11 (46)17 (24)35 (21)79 (27)
Bilateral2 (8.3)4 (5.6)12 (7.2)22 (7.6)
Unknown*0 (0)3 (4.2)5 (3.0)9 (3.1)
Vegetation valve or site†Aortic9 (38)16 (23)13 (7.8)49 (17)
Mitral5 (21)7 (9.9)35 (21)60 (21)
Tricuspid12 (50)50 (70)123 (74)198 (68)
Pulmonic0 (0)2 (2.8)2 (1.2)4 (1.4)
Non-valvular‡0 (0)0 (0)1 (0.6)2 (0.7)
Unknown*0 (0)3 (4.2)5 (3.0)9 (3.1)
Congenital heart disease§Yes0 (0)0 (0)1 (0.6)1 (0.3)
Other valve disease¶Yes1 (4.2)0 (0)2 (1.2)4 (1.4)
Echocardiogram performedBoth TTE** and TEEπ14 (58)38 (54)73 (44)136 (47)
TTE** only10 (42)32 (45)93 (56)152 (52)
None0 (0)1 (1.4)0 (0)2 (0.7)
Cardiac complications†Myocardial abscess1 (4.2)4 (5.6)7 (4.2)14 (4.8)
Aortic root abscess1 (4.2)3 (4.2)4 (2.4)10 (3.4)
Heart failure4 (17)15 (21)21 (13)47 (16)
Conduction delay3 (12)1 (1.4)1 (0.6)6 (2.1)
Vascular complications†Ischaemic stroke5 (21)10 (14)21 (13)46 (16)
Intracerebral haemorrhage2 (8.3)6 (8.5)9 (5.4)24 (8.3)
Mycotic aneurysm1 (4.2)3 (4.2)5 (3.0)13 (4.5)
Septic pulmonary emboli10 (42)44 (62)110 (66)177 (61)
Hepatic infarct0 (0)2 (2.8)0 (0)4 (1.4)
Mesenteric ischaemia0 (0)1 (1.4)0 (0)2 (0.7)
Renal infarct0 (0)4 (5.6)0 (0)14 (4.8)
Limb ischaemia0 (0)0 (0)0 (0)2 (0.7)
Invasive infection†CNS infection††3 (12)6 (8.5)14 (8.4)29 (10)
Septic arthritis2 (8.3)7 (9.9)21 (13)32 (11)
Osteomyelitis2 (8.3)5 (7.0)15 (9.0)25 (8.6)
Secondary bacteraemia‡‡Yes1 (4.2)22 (31)36 (22)58 (20)
Antimicrobial treatmentWholly inpatient, wholly IV11 (46)41 (58)94 (56)162 (56)
Wholly inpatient, part oral0 (0)7 (9.9)18 (11)26 (9.0)
Part outpatient, wholly IV11 (46)19 (27)31 (19)72 (25)
Part outpatient, part IM0 (0)0 (0)2 (1.2)2 (0.7)
Part outpatient, part oral2 (8.3)4 (5.6)21 (13)28 (9.7)
Surgical treatment†Any surgical intervention6 (25)16 (23)17 (10)49 (17)
Device insertion or removal1 (4.2)4 (5.6)5 (3.0)5 (1.7)
Valve repair5 (21)9 (13)12 (7.2)32 (11)
Valve replacement, any3 (12)11 (15)4 (2.4)25 (8.6)
Valve replacement, biologic1 (4.2)8 (11)4 (2.4)17 (5.8)
Valve replacement, mechanical2 (8.3)3 (4.2)0 (0.0)9 (3.1)
Valve repair and replacement2 (8.3)4 (5.6)1 (0.6)10 (3.4)
Length of stayMean days (SD)21.5 (18.1)32.4 (23.8)31.7 (23.9)29.7 (23.1)
Left against medical adviceYes4 (17)10 (14)46 (28)62 (21)
Opiate used§§Hydromorphone IR¶¶0 (0)51 ()120 ()171 (59***)
Hydromorphone CRχ0 (0)21 ()3253 (18***)
Morphine0 (0)11 (15)35 (21)46 (16***)
Fentanyl0 (0)5 (7.0)7 (4.2)12 (4.1***)
Heroin0 (0)3 (4.2)11 (6.6)14 (4.8***)
Oxycodone0 (0)14 (20)22 (13)36 (12***)
Oxycodone-acetaminophen0 (0)4 (5.6)5 (3.0)9 (3.1***)
Stimulant used§§Methamphetamine18 (75)0 (0)131 (79)149 (51)
Cocaine10 (42)0 (0)68 (41)78 (27***)
Crack4 (17)0 (0)14 (8.4)28 (9.7***)
Bupropion1 (4.2)0 (0)1 (0.6)2 (0.7***)
Methylphenidate3 (12)0 (0)18 (11)21 (7.2***)
Addictions counselling referralYes6 (25)29 (41)66 (40)103 (56)
Opioid substitution therapy†††Yes7 (29)11 (15)27 (16)48 (17)
DeathNo18 (75)49 (69)127 (77)209 (72)
Yes, during this episode5 (21)9 (13)18 (11)43 (15)
Yes, during full follow-up period6 (25)22 (31)39 (23)81 (28)
Microbiology†Staphylococcus aureus18 (75)58 (82)151 (91)245 (84)
MSSA15 (62)43 (61)113 (68)184 (63)
MRSA3 (12)15 (21)38 (23)61 (21)
Viridans-group strep3 (12)2 (2.8)10 (6.0)19 (6.6)
Non-viridans strep1 (4.2)3 (4.2)5 (3.0)12 (4.1)
Enterococci (all Enterococcus faecalis)3 (12)4 (5.6)5 (3.0)17 (5.9)
Enterobacterales1 (4.2)2 (2.8)0 (0)5 (1.7)
Pseudomonas or acinetobacter0 (0)0 (0)4 (2.4)4 (1.4)
Bartonella henselae0 (0)1 (1.4)1 (0.6)2 (0.7)
Burkholderia cepacia0 (0)1 (1.4)0 (0)1 (0.3)
Actinomyces odontolyticus1 (4.2)0 (0)0 (0)1 (0.3)
Candida albicans0 (0)1 (1.4)1 (0.6)2 (0.7)
Polymicrobial3 (12)5 (7.0)14 (8.4)22 (7.6)
Culture negative0 (0)2 (2.8)4 (2.4)6 (2.1)
  • *Definite endocarditis by modified Duke criteria with no evidence of vegetation on echocardiogram.

  • †Sum to more than 100% because the categories are not mutually exclusive.

  • ‡Includes atrial and right ventricular vegetations.

  • §Single included patient with congenital heart disease had coarctation of the aorta, without prosthesis.

  • ¶All patients with underlying valvular disease had bicuspid aortic valves. The patient with coarctation also had bicuspid valve and is included in this count. We note that the patient who injected only stimulants and had a bicuspid aortic valve was diagnosed with mitral valve endocarditis.

  • **Transthoracic echocardiogram π transoesophageal echocardiogram.

  • ††CNS infection, including meningitis, brain abscess, epidural abscess or paraspinal abscess; septic emboli leading to stroke are captured separately as ‘ischaemic stroke’ above.

  • ‡‡As defined in Tan et al24 identification of a microorganism in blood culture, not secondary to an infection at another body site, different from that grown on index blood cultures at the time of infective endocarditis diagnosis; obtained at least 48 hours after index blood cultures and while the patient was receiving parenteral antimicrobials; not associated with a new vegetation; presumed to be due to direct inoculation.

  • §§Use within 3 months of admission.

  • ¶¶Hydromorphone immediate release, most commonly sold by brand name dilaudidχhydromorphone controlled release, most commonly sold by brand name Hydromorph Contin.

  • ***Percentages are of known use among all patients; denominator includes 29 patients with unknown substance use.

  • †††Methadone, suboxone, naloxone.

  • CNS, central nervous system; CRχ, continuous-release; IM, intramuscular; IR, immediate-release; IV, intravenous; MRSA, Methicillin-resistant Staphylococcus aureus; MSSA, Methicillin sensitive Staphylococcus aureus.