Infective Endocarditis due to Non-HACEK Gram-Negative Bacilli: Clinical Characteristics and Risk Factors from a Prospective Multicenter Brazilian Cohort

Abstract

<b>Background:</b> Non-HACEK Gram-negative bacilli (NGNB) infective endocarditis (IE) has a growing frequency. We aimed to describe cases of NGNB IE and find associated risk factors. <b>Methods:</b> We conducted a prospective observational study of consecutive patients with definitive IE according to the modified Duke criteria in four institutions in Brazil. <b>Results:</b> Of 1154 adult patients enrolled, 38 (3.29%) had IE due to NGNB. Median age was 57 years, males predominated, accounting for 25/38 (65.8%). Most common etiologies were <i>Pseudomonas aeruginosa</i> and <i>Klebsiella</i> spp. (8 episodes, 21% each). Worsening heart failure occurred in 18/38 (47.4%). Higher prevalence of embolic events was found (55,3%), mostly to the central nervous system 7/38 (18.4%). Vegetations were most commonly on aortic valves 17/38 (44.7%). Recent healthcare exposure was found in 52.6% and a central venous catheter (CVC) in 13/38 (34.2%). Overall mortality was 19/38 (50%). Indwelling CVC (OR 5.93; 95% CI, 1.29 to 27.3; <i>p</i> = 0.017), hemodialysis (OR 16.2; 95% CI, 1.78 to 147; <i>p</i> = 0.008) and chronic kidney disease (OR 4.8; 95% IC, 1.2 to 19.1, <i>p</i> = 0.049) were identified as risk factors for mortality. <b>Conclusions:</b> The rate of IE due to NGNB was similar to that in previous studies. <i>Enterobacterales</i> and <i>P. aeruginosa</i> were the most common etiologies. NGNB IE was associated with central venous catheters, prosthetic valves, intracardiac devices and hemodialysis and had a high mortality rate.