What question did this study set out to answer?

This case aims to highlight the challenges in diagnosing infective endocarditis (IE) associated with recurrent Staphylococcus aureus bacteraemia when initial imaging is inconclusive.

May 18, 2026Open Access

Delayed Diagnosis of Native-Valve Infective Endocarditis Presenting as Progressive Aortic Regurgitation in Recurrent Methicillin-Sensitive Staphylococcus aureus Bacteraemia With Initially Negative TTE and FDG PET-CT

Key Points

This case aims to highlight the challenges in diagnosing infective endocarditis (IE) associated with recurrent Staphylococcus aureus bacteraemia when initial imaging is inconclusive.
Detailed clinical evaluation of a 55-year-old woman with recurrent methicillin-sensitive Staphylococcus aureus bacteraemia.
Initial diagnostic imaging included transthoracic echocardiography and positron emission tomography/computed tomography, both of which were negative for endocarditis.
Transoesophageal echocardiography was subsequently employed after clinical deterioration, confirming severe aortic regurgitation indicative of IE.
Blood cultures confirmed methicillin-sensitive Staphylococcus aureus (MSSA) infection, with initial imaging failing to demonstrate endocarditis.
After two weeks of antibiotic therapy, blood culture clearance was achieved, but clinical symptoms persisted until the diagnosis of IE was made via transoesophageal echocardiography.
Patient was managed conservatively due to underlying liver disease, completing six weeks of intravenous antibiotics.

Abstract

Infective endocarditis (IE) remains a life-threatening condition in which early diagnosis is essential to prevent valvular destruction and systemic complications. Persistent Staphylococcus aureus bacteraemia (SAB) is strongly associated with endocardial infection, yet diagnosis may be challenging when initial imaging is inconclusive. We describe a case of a 55-year-old woman who presented with fever, vomiting, and transient loss of consciousness. Blood cultures grew methicillin-sensitive Staphylococcus aureus (MSSA). Initial transthoracic echocardiography (TTE) and positron emission tomography-computed tomography (PET-CT) imaging failed to identify endocarditis. Despite appropriate antimicrobial therapy, she developed recurrent bacteraemia, ongoing pyrexia, and clinical deterioration. Transoesophageal echocardiography (TOE) subsequently demonstrated severe aortic regurgitation consistent with IE. Because of significant underlying liver disease, surgery was deemed prohibitive, and she was managed with prolonged intravenous antibiotics and cardiology follow-up for potential future valve intervention. This case highlights the importance of maintaining a high clinical suspicion for IE in patients with persistent SAB. It supports guideline recommendations for early TOE when clinical suspicion remains high despite a negative transthoracic study. The final Duke-International Society for Cardiovascular Infectious Diseases (ISCVID) 2023 classification of the case aligned with definite IE. The patient completed six weeks of antibiotic treatment after blood culture clearance, which was achieved at week two following the start of antibiotic therapy.

Perguntar à IA

Bookmark

View Full Paper