A Man With Embolic Events and an Unusual Cardiac Mass

Key TakeawaysA 60-year-old man presented with acute neurologic symptoms weeks after a ulnar artery thrombus. Brain imaging showed multiple ischemic lesions, and cardiac imaging revealed a mass. Although initial blood cell culture reports were negative, surgery and subsequent testing identified Streptococcus mitis infective endocarditis. The case highlights endocarditis as a possible cause of embolic events, even without fever or initially positive blood cell culture reports.The case report by internist Christopher Fritzsche and colleagues at the Ente Ospedaliero Cantonale in Lugano, Switzerland, reminds clinicians of the value of a comprehensive diagnostic workup.The Patient and His Medical HistoryThe patient presented to the emergency department of a hospital in Lugano with acute-onset dysarthria, clonic jaw movements, and a rightward deviation of gaze. His National Institutes of Health Stroke Scale score was 2. Several weeks earlier, a thrombus in the left ulnar artery had led to peripheral ischemia, which had been confirmed by CT.There were no known chronic conditions.The patient’s medical history, including family, social, and travel history and the history of medications, substance use, and allergies was unremarkable.FindingsUpon admission, the patient’s vital signs were measured. Blood pressure was 154 mm Hg. Body temperature, respiratory rate, heart rate, and oxygen saturation in room air were within normal limits.Inspection, auscultation, palpation, and percussion of the patient’s body yielded no significant findings.Laboratory results revealed, among other things, elevated lactate dehydrogenase, mild inflammatory syndrome, mild normocytic anemia, and mild renal impairment. Coagulation parameters were within normal limits. Blood cell culture results were negative.Given the suspicion of blood culture-negative endocarditis, serologic tests were performed for Brucella species, Coxiella burnetii, Bartonella henselae, HIV, and syphilis, all of which yielded negative results. CT and MRI of the brain revealed multiple acute to subacute ischemic lesions in the supratentorial and infratentorial cerebral parenchyma. A lumbar puncture showed no pleocytosis. EEG showed no epileptic activity.DiagnosisTransthoracic echocardiogram revealed anechoic lesions in the basal anterior and anterolateral walls of the left ventricle. Transesophageal echocardiography showed a mass approximately 2 cm in size with mobile and irregular margins, attached to the basal segments of the anterior, anterolateral, and lateral walls of the left ventricle. Due to its atypical shape and unclear origin, the lesion was classified as potentially neoplastic.Following a multidisciplinary consultation, 18F-deoxyglucose PET/CT was performed. The lesion showed increased metabolic activity, but no other extracardiac site of infection or malignancy.Excision of the cardiac mass during mitral valve replacement was followed by histopathologic examination. This revealed ulcerative and purulent endocarditis with extension of the inflammatory process into the adjacent myocardium and endocardium. Whole-genome sequencing ultimately identified S mitis. Repeat blood cell cultures confirmed the finding.Discussion“Infective endocarditis is a potentially life-threatening disease with a broad and sometimes misleading clinical and radiological presentation,” wrote the authors of the case report. This case shows that infectious endocarditis must be considered in the differential diagnosis when patients present with multiple systemic embolic events and an unclear cardiac mass, even if fever or positive blood cell cultures are initially absent.This story was translated from Univadis Germany, part of the Medscape Professional Network.