Fever in a patient with valve disease or a prosthetic valve: suspected endocarditis
BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.
Unexplained fever in an at-risk patient: before any antibiotic
Blood cultures, before any antibiotic therapy
- Blood cultures: at least 3 pairs (aerobic and anaerobic bottles), 10 mL of blood per bottle, by peripheral venepuncture, without waiting for a fever spike; write "suspected endocarditis" on the request
Laboratory tests
- FBC
- CRP
- Serum creatinine with eGFR
Urine tests
- Urine dipstick (haematuria, proteinuria)
Do not order
- “Trial” antibiotic before blood cultures in a patient at risk: this is the leading cause of culture-negative endocarditis [2,3].
- A single pair of blood cultures: insufficient, an isolated positive blood culture should be interpreted with caution [2]; at least two positive pairs are needed for a typical organism and three for an unusual one in the Duke-ISCVID criteria [3].
Negative blood cultures or antibiotic already given (after specialist advice)
Blood cultures
- Repeat blood cultures after stopping the antibiotic (stable patient, on specialist advice)if needednon-French guidelineStable patient, subacute symptoms, no local or distant complication, who has received a very short course of antibiotics: ESC states that stopping the antibiotic and repeating the blood cultures may be necessary [2].
Serology
- Chronic Q fever serology (Coxiella burnetii, phase I and II IgG and IgA)
- Bartonella serology
Sources (9)
- Selton-Suty C, Célard M, Le Moing V, et al.; AEPEI Study Group. Preeminence of Staphylococcus aureus in infective endocarditis: a 1-year population-based survey. Clin Infect Dis. 2012;54(9):1230-9.
- Delgado V, Ajmone Marsan N, de Waha S, et al.; ESC Scientific Document Group. 2023 ESC Guidelines for the management of endocarditis. Eur Heart J. 2023;44(39):3948-4042.
- Fowler VG, Durack DT, Selton-Suty C, et al. The 2023 Duke-International Society for Cardiovascular Infectious Diseases Criteria for Infective Endocarditis: Updating the Modified Duke Criteria. Clin Infect Dis. 2023;77(4):518-26.
- Gould FK, Denning DW, Elliott TSJ, et al. Guidelines for the diagnosis and antibiotic treatment of endocarditis in adults: a report of the Working Party of the British Society for Antimicrobial Chemotherapy. J Antimicrob Chemother. 2012;67(2):269-89.
- Nakatani S, Ohara T, Ashihara K, et al. JCS 2017 Guideline on Prevention and Treatment of Infective Endocarditis. Circ J. 2019;83(8):1767-1809.
- Pierce D, Calkins BC, Thornton K. Infectious endocarditis: diagnosis and treatment. Am Fam Physician. 2012;85(10):981-6.
- National Institute for Health and Care Excellence. Prophylaxis against infective endocarditis. NICE guideline CG64, publiée le 17 mars 2008, dernière mise à jour le 8 juillet 2016.
- Nohria R, Romaine A, Garcia-Sampson G. Infective Endocarditis: Diagnosis and Treatment. Am Fam Physician. 2026;113(2):145-152.
- Assurance maladie. Nomenclature des actes de biologie médicale (NABM), version 105 : actes 1316, 1248 et 1249 (fièvre Q), 1331 (bartonelloses), 5219 et 5221 (hémocultures).