Fever, dyspnea, and a new heart murmur
A 35-year-old man presented to the emergency department because of night sweats, fever, chills, and shortness of breath. He also had an acute onset of blue discoloration of his right fourth finger. His symptoms (except for the finger discoloration) had begun about 6 months previously and had rapidly progressed despite several courses of different antibiotics of different types, given both intravenously in the hospital and orally at home. He had lost 20 lb during this time. Previously, he had been healthy.
About 1 month after his symptoms began, he had consulted his primary care physician, who detected a new grade 4/6 systolic and diastolic murmur. Transthoracic echocardiography about 2 months after that demonstrated mild aortic and mitral insufficiency but no echocardiographic features supporting infective endocarditis. Of note, the patient had no risk factors for endocarditis such as illicit drug use or poor dental health.
In the emergency department, his temperature was 99.4°F (37.4°C), pulse 109 beats per minute, and blood pressure 126/60 mm Hg. He had a grade 3/6 harsh holosystolic murmur best heard at the right upper sternal border, a grade 3/4 holodiastolic murmur audible across the precordium, and a grade 3/4 holosystolic blowing murmur best heard at the cardiac apex. Other findings included signs of aortic insufficiency—the Duroziez sign (a diastolic murmur heard over the femoral artery when compressed), Watson’s water-hammer pulse (indicating a wide pulse pressure), and the Müller sign (pulsation of the uvula)—and small Janeway lesions on the inner aspect of his right arm and palm.
,Electrocardiography showed normal sinus rhythm, PR interval 128 ms, QRS complex 100 ms, QT interval 360 ms, and corrected QT interval 473 ms.
Blood cultures grew Streptococcus sanguinis. Both transthoracic and transesophageal echocardiography were done promptly and revealed multiple mobile echodensities attached to a trileaflet aortic valve, consistent with vegetations and valve leaflet destruction; severe (4+) aortic regurgitation with flow reversal in the abdominal aorta; mild mitral regurgitation; and a mitral valve aneurysm with mild mitral regurgitation (Figure 1).
INFECTIVE ENDOCARDITIS: WORTH CONSIDERING
S sanguinis is a member of the group of viridans streptococci. As a normal inhabitant of the healthy human mouth, it is found in dental plaque. It may enter the bloodstream during dental cleaning and may colonize the heart valves, particularly the mitral and aortic valves, where it is the most common cause of subacute bacterial endocarditis.
Infective endocarditis is often diagnosed clinically with the Duke criteria (www.med-calc.com/endocarditis.html).1 However, the variability of the clinical presentation and the nonspecific nature of the initial workup often create a diagnostic challenge for the evaluating physician.1,2
In cases of recurrent persistent fever and a new heart murmur, infective endocarditis must always be considered. Blood cultures should be ordered early and repeatedly. If blood cultures are positive, transesophageal echocardiography should be done without delay if transthoracic echocardiography was unremarkable. Prompt diagnosis and surgical intervention prevent complications.
