An aortic root abscess in a patient with a bicuspid aortic valve: a case report

Background Infective endocarditis is a serious infection associated with high mortality and severe complications, such as heart failure, uncontrolled infection, and embolic events. Certain populations, including individuals with a prosthetic valve and those with native valve disease, such as bicuspid aortic valve, are considered to be more at risk of developing infective endocarditis. Case summary A 51-year-old previously healthy male presented with a 2-week history of persistent fever, malaise, and night sweats despite taking a long course of oral antibiotics. Examination was unremarkable; however, blood tests showed elevated inflammatory markers. Three sets of blood cultures revealed coagulase-negative gram-positive cocci (later identified as Staphylococcus lugdunensis), and the patient was subsequently started on IV antibiotics. His echocardiography showed a bicuspid aortic valve with severe regurgitation, and an aortic root abscess surrounding a dilated aortic root. In view of the presence of locally uncontrolled infection, the patient was referred for urgent debridement of the abscess and replacement of the aortic valve with tissue prosthesis. Fortunately, after a total of 6 weeks of IV antibiotics and successful operative management, our patient made a complete recovery. Discussion The development of an aortic root abscess occurs in 10-40% of cases of aortic valve endocarditis. Clinically, this should be suspected in any patient with endocarditis who fails to improve despite appropriate antibiotic therapy. This case demonstrates that severe infective endocarditis can develop in apparently healthy individuals due to underlying cardiac abnormalities.