Infective endocarditis secondary to unsual organisms: A descriptive study

Abstract

Progress in molecular microbiology and serologies have increased the proportion of IE associated with infrequent microorganisms therefore reduced the proportion of infective endocarditis (IE) with no microbiological documentation, however infective endocarditis due to these unsual agents still not well studied. We performed a decriptive study of a retrospective Infective endocarditis population admitted to a tertiary hospital between 2014 and 2019. Unusual-microorganism IE was defined as definite IE based on Dukes criterias, due to microorganisms other than streptococci, staphylococci, or enterococci. Of 114 cases of documented IE, 10 (8.7%) were due to unusal microorganisms; the following species were involved: Candida (n = 3), Bacillus (n = 2), Gemella morbillifom (n = 2), Enteroccocus Casseflavus (n = 1), and Klebsiella (n = 1) Nisseriae (n = 1). Cases were documented with blood cultures (n = 7, 70%), or serology (n = 3). As compared with IE due to staphylococci, streptococci, or enterococci, IE due to unusual microorganisms occurred more frequently in patients with prosthetic valve (20% vs. 11%; P = .06), without previously known heart disease (70% vs 52.9%; P = .05), longer duration of fever (mean, 35 days vs 15; P = .04); no differences were noted in terms of hospital stay (28.5 days vs 28 days), However mortality rate was significantly higher in group with atypical agents IE (20% vs. 5% P < 0.05) In this population-based study, 8.7% of IE cases were due to unusual microorganisms, with a predominance of anaerobes, yeast, and gram-negative bacilli. As compared with IE related to staphylococci, streptococci, or enterococci, IE cases related to unusual microorganisms were associated with prosthetic valves, longer duration of fever, and higher mortality rate.