Firstline - Clinical Decisions

Microbiologic Criteria

Microorganisms that commonly cause IE isolated from two or more separate blood culture sets

Staphylococcus aureus
Staphylococcus lugdunensis
Enterococcus faecalis
all streptococcal species (except for S. pneumoniae and S. pyogenes)
Granulicatella and Abiotrophia spp.
Gemella spp.
HACEK group microorganisms (Haemophilus species, Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae)
In the setting of intracardiac prosthetic material, the following additional bacteria should be included as “typical” pathogens:
- coagulase negative staphylococci
- Corynebacterium striatum and C. jeikeium
- Serratia marcescens
- Pseudomonas aeruginosa
- Cutibacterium acnes
- non-tuberculous mycobacteria (especially M. chimaerae)
- Candida spp.

Microorganisms that occasionally or rarely cause IE isolated from three or more separate blood culture sets

Positive PCR or other nucleic acid-based technique for Coxiella burnetii, Bartonella species, or Tropheryma whipplei from blood

Coxiella burnetii antiphase I IgG antibody titer > 1:800, or isolated from a single blood culture

Indirect immunofluorescence assays (IFA) for detection of IgM and IgG antibodies to Bartonella henselae or Bartonella quintana with IgG titer > 1:800

Imaging Criteria

Echocardiography and/or Cardiac CT showing vegetation, valvular/leaflet perforation, valvular/leaflet aneurysm, abscess, pseudoaneurysm, or intracardiac fistula

Significant new valvular regurgitation on echocardiography as compared to previous imaging

Worsening or changing of pre-existing regurgitation is not sufficient

New partial dehiscence of prosthetic valve as compared to previous imaging

Abnormal [18F]FDG PET/CT Imaging

Performed at least 3 months after prosthetic valve surgical implantation
Abnormal metabolic activity involving a native or prosthetic valve, ascending aortic graft (with concomitant evidence of valve involvement), intracardiac device leads or other prosthetic material

Surgical Criteria

Evidence of IE documented by direct inspection during heart surgery neither Major Imaging Criteria nor subsequent histologic or microbiologic confirmation

This major criterion should not be interpreted as giving license to not send appropriate samples for histopathology and microbiological studies

Modified Duke 2023: Major Criteria

Major Criteria