Facet joint arthritis as the presenting symptom for culture-negative Aggregatibacter aphrophilus native valve endocarditis in a patient without known cardiac disease: a case report

This is the first reported case of culture-negative native valve IE caused by A. aphrophilus presenting with facet joint arthritis in a patient without known cardiac disease. Our case emphasizes the importance of considering IE in patients with fever and unexplained musculoskeletal pain, even without known cardiac disease. When conventional diagnostic tests are inconclusive, br-PCR on excised valve tissue is indispensable. Further improvements in non-invasive diagnostic methods are needed to facilitate early diagnosis and treatment.