A Contemporary Picture of Coagulase-Negative Staphylococcal Endocarditis: A Nationwide GAMES Cohort Study

Abstract

Background: Coagulase-negative staphylococci (CoNS) are an increasingly common cause of infective endocarditis (IE) and lack recent data from large studies.

Objectives: Our aim was to describe the epidemiology, clinical characteristics, and outcomes of staphylococcal IE in a contemporary nationwide cohort study, while comparing coagulase-negative staphylococcal IE (CoNSIE) to IE from Staphylococcus aureus (SAIE), and among IE caused by Staphylococcus epidermidis (SE), S. lugdunensis (SL), and other CoNS.

Methods: We completed a post hoc analysis of a prospectively collected cohort of 4,567 consecutive definitive IE episodes from 44 Spanish centers between 2008 and 2022 (GAMES ["Grupos de Apoyo al Manejo de la Endocarditis Infecciosa en España"] cohort). A total of 842 cases of CoNSIE were compared with 1,109 cases of SAIE. Additionally, 647 episodes caused by SE were compared with 54 caused by SL and 109 caused by 9 other known CoNS species. Multivariate analyses were performed to investigate prognostic factors for in-hospital and 1-year mortality.

Results: Staphylococci accounted for 1,951 (42.7%) episodes of IE. The predominant CoNS etiology was SE (76.8%), followed by SL (6.4%), S. capitis (3.5%), S. haemolyticus (3.2%), S. hominis (3.2%), S. warneri (1.5%), and 5 other species. CoNSIE showed a distinct clinical profile from SAIE (older age, higher rates of prior heart disease, aortic and prosthetic valve involvement, nosocomial acquisition, methicillin resistance, intracardiac complications, and cardiac surgery), while in-hospital mortality was higher in SAIE (32.8% vs 37.1%; P = 0.049), with no significant differences in 1-year mortality. S. lugdunensis displayed a shorter course of infection and higher rates of leaflet perforation/rupture than S. epidermidis and other CoNS, but cardiac surgery rates (60.4% vs 61.1% vs 56.0%; P = 0.850), as well as in-hospital (33.1% vs 37.0% vs 27.5%; P = 0.540) and 1-year mortality rates were high and similar in all groups. Septic shock, heart failure, and cardiac surgery (protective) were consistently identified as independent prognostic factors, whereas none of the staphylococcal species were independently associated with mortality. Last, each 5-year study period was independently associated with a reduction in staphylococcal in-hospital and 1-year mortality.

Conclusions: CoNSIE was a relatively common (18.4%) and life-threatening entity with particularities by species yet generally high rates of surgery and mortality, although its prognosis improved over time.

Keywords: coagulase-negative; endocarditis; epidermidis; lugdunensis; prognosis; staphylococci.