MRCP2-0341
A 45-year-old man, who was previously healthy and physically fit, presented to the Emergency department with left-sided weakness that lasted for two hours. However, the weakness resolved by the time he arrived at the hospital. A CT scan of his head was normal, with no signs of haemorrhage or infarction.
The patient is a non-smoker, has no history of hypertension or hypercholesterolaemia, and there is no family history of cerebrovascular disease. During the examination, a soft diastolic murmur was heard in the aortic area, and the patient had a fever of 38.2°C. Upon further questioning, he reported feeling lethargic and experiencing rigors for the past two weeks.
A transthoracic echocardiogram and transoesophageal echocardiogram revealed a suspicious mobile mass on the aortic valve with moderate aortic regurgitation. Blood cultures showed that the patient was infected with Staphylococcus aureus, which was sensitive to flucloxacillin. The patient was started on appropriate antibiotic therapy for infective endocarditis after consulting with the microbiologist.
However, two weeks later, the patient still had a daily fever that reached 38.5°C. What is the next most appropriate step?