963. External Validation of the 2023 Duke - International Society for Cardiovascular Infectious Diseases (ISCVID) Diagnostic Criteria for Infective Endocarditis (IE)

BACKGROUND: The 2023 Duke-ISCVID criteria for IE were recently introduced to improve classification of IE for research and clinical purposes (Table 1). We compared the diagnostic accuracy of the new criteria with the 2000 modified Duke criteria, the 2015 European Society of Cardiology (ESC) criteria and a clinically adjudicated reference standard by a panel of international experts on IE. [Figure: see text] Adapted from: Fowler et al, Clinical Infectious Diseases, 2023 METHODS: The study population consisted of consecutively enrolled patients suspected to have IE and discussed by the IE team of the Amsterdam University Medical Center (AMC) between October 2016 and March 2021. A panel of international experts on IE assigned a final diagnosis, which served as the reference standard. We compared the definite classification of the 2023 Duke-ISCVID criteria against this reference standard. We also evaluated accuracy of the new criteria, excluding data obtained from cardiac surgery and pathology (“Clinical Criteria”). Lastly, we quantified the added value of the proposed changes to the criteria, and compared the 2023 Duke-ISCVID to previous criteria using the McNemar test. We performed sensitivity analyses in patients who underwent cardiac surgery and patients who underwent TEE. RESULTS: 595 patients with suspected IE were included, of whom 399 (67%) were adjudicated as having IE. 111 patients (19%) had prosthetic valve IE, 48 (8%) had cardiac implantable electronic device IE. The 2023 Duke-ISCVID criteria were more sensitive than the modified Duke or ESC criteria (84.2 vs 74.9 vs 80%,respectively, p < 0.001 for ISCVID vs ESC criteria) without significant loss of specificity (Table 2). After excluding cardiac surgery/pathology results, the 2023 Duke-ISCVID Clinical Criteria also had significantly better sensitivity than the modified Duke and ESC criteria, again without losing specificity. The changes in the 'major microbiological' and 'imaging' criteria had the most impact (Figure 1). Findings were robust in sensitivity analyses (Table 3). When classifying ‘definite’ and ‘possible’ IE as a positive test, the 2023 Duke-ISCVID criteria had 99% sensitivity compared to the reference standard, but specificity decreased to 21%. [Figure: see text] Sensitivity and specificity are against the reference standard (adjudication panel). The Clinical Criteria classification is the Duke-ISCVID classification when results from surgery or post-mortem studies are not used to determine classification. [Figure: see text] In the Definite + Possible analysis, patients with possible IE according to the Duke-ISCVID criteria were also considered as having IE. All comparisons are against the reference standard (adjudication panel). CONCLUSION: In this cohort, the 2023 Duke-ISCVID criteria represent a significant advance in the diagnostic classification of patients suspected of IE. Added value of new Duke-ISCVID criteria compared to modified Duke criteria [Figure: see text] Each point (red square for sensitivity, blue circle for specificity) provides the diagnostic accuracy measure for the 2000 modified Duke Criteria with addition of a specific change from the Duke-ISCVID criteria. The horizontal bars represent the 95% confidence interval for the point estimate. The top points represent the modified Duke criteria without addition, the bottom points are the complete Duke-ISCVID criteria. DISCLOSURES: Larry M. Baddour, MD, Boston Scientific: Advisor/Consultant|Roivant Sciences: Advisor/Consultant Arnold S. Bayer, MD, Akagera Medicines: Grant/Research Support|ContraFect Corporation: Grant/Research Support Emanuele Durante Mangoni, MD,, PhD, Advanz pharma: Advisor/Consultant|Advanz pharma: Grant/Research Support|Advanz pharma: Honoraria|Angelini: Grant/Research Support|Angelini: Honoraria|Genentech: Advisor/Consultant|Genentech: Board Member|Genentech: Honoraria|Infectopharm: Grant/Research Support|Menarini: Board Member|Menarini: Honoraria|Pfizer: Advisor/Consultant|Pfizer: Board Member|Pfizer: Grant/Research Support|Pfizer: Honoraria|Roche: Advisor/Consultant|Roche: Board Member|Roche: Honoraria Thomas L. Holland, MD, Aridis: Advisor/Consultant|Basilea Pharmaceutica: Advisor/Consultant|Karius: Advisor/Consultant|Lysovant: Advisor/Consultant Adolf W. Karchmer, MD, Karius: Grant/Research Support|Up To Date: Honoraria Vance G. Fowler, MD, MHS, Amphliphi Biosciences, Integrated Biotherapeutics; C3J, Armata, Valanbio; Akagera, Aridis, Roche, Astra Zeneca: Advisor/Consultant|Genentech, Regeneron, Deep Blue, Basilea, Janssen;: Grant/Research Support|Infectious Diseases Society of America: Honoraria|MedImmune, Allergan, Pfizer, Advanced Liquid Logics, Theravance, Novartis, Merck; Medical Biosurfaces; Locus; Affinergy; Contrafect; Karius;: Grant/Research Support|Novartis, Debiopharm, Genentech, Achaogen, Affinium, Medicines Co., MedImmune, Bayer, Basilea, Affinergy, Janssen, Contrafect, Regeneron, Destiny,: Advisor/Consultant|Sepsis diagnostic: Patent pending|UpToDate: Royalties|Valanbio and ArcBio: Stock Options