Culture-negative endocarditis with neurologic presentations and dramatic response to heparin: a case report

Blood culture-negative endocarditis (BCNE) is diagnosed in 2–7% of patients with infective endocarditis (IE) and recent antibiotic use is a known risk factor. Altered mental status may be a presenting symptom. Besides empiric antibiotics, intravenous anticoagulation using heparin may have a role in the management of such patients.

A 23-year-old male patient was referred to our center with fever, altered mental status and abnormal gait. Neurologic examination revealed Wernicke’s aphasia. Cardiac auscultation revealed systolic murmur at the left sternal border. ECG (electrocardiogram) was unremarkable. Brain MRI showed multiple cerebellar lesions. Transthoracic echocardiography (TTE) demonstrated three large masses on the right ventricle (RV), tricuspid valve (TV), and anterior mitral valve (MV) leaflet. Blood cultures (three sets) were negative. Intravenous heparin therapy was administered. After 48 h, the second TTE demonstrated that one valvular lesion disappeared and the other two lesions showed a significant decrease in size. The patient’s neurological symptoms resolved gradually. Further workup for collagen vascular disorders did not show any abnormality.

BCNE should be considered in patients with fever and neurologic manifestations. TTE should be performed to detect valvular abnormalities. Intravenous heparin could be used in such patients when TTE demonstrate valvular vegetations.