Case Presentation: A previously healthy53-year-old male, who had undergone dental treatment one week before, was transfered to our hospital with the symptoms of acute-onset cephalgia and right homonymous hemianopia. Upon physical examination, cardiac auscultation revealed a pan-systolic murmur (Levine 2/6), with maximal intensity at the apex. Laboratory analyses revealed leukocytosis with a white blood cell count of 9,500/μL, and an elevated C-reactive protein of 16.3 mg/dL. Cerebral magnetic resonance imaging demonstrated diffuse multiple microhemorrhages and cerebral angiography revealed a cerebral aneurysm in the left posterior cerebral artery. Transthoracic echocardiography demonstrated severe mitral valve regurgitation with posterior leaflet prolapse and about 7mm vegetation on the anterior mitral leaflet. Digital subtraction angiography performed the following day revealed a cerebral aneurysm in the left posterior cerebral artery. Based on clinical diagnosis of infective endocarditis, empiric antimicrobial therapy was initiated with intravenous ceftriaxone and vancomycin. By hospital day 9, three sets of blood cultures yielded Gram-positive organisms, subsequently identified as Rothia dentocariosa, confirming the diagnosis of infective endocarditis (IE). The anti-microbial regimen was modified to intravenous ampicillin on hospital day 11. The patient collapsed with acute neurological deterioration manifesting as disorientation and apraxia due to cerebral aneurysmal progression, which neeeded urgent endovascular coil embolization. Following confirmation of blood culture sterility, a six-week course of intravenous antimicrobial therapy was completed. The patient successfully underwent mitral valve repair through right thoracotomy, with no gross evidence of residual vegetation.
Discussion: R. dentocariosa, a pleomorphic gram-positive microorganism, predominantly colonizes the oropharyngeal cavity and upper respiratory tract. Despite its relatively low virulence, R. dentocariosa can occasionally precipitate systemic infections. Among these manifestations, infective endocarditis represents the most frequently documented condition, though merely exceeding 50 documented cases in the literature. Structural valvular abnormalities and oral pathologies constitute principal risk factors for endocarditis development. R. dentocariosa endocarditis exhibits a distinctive clinical profile characterized by elevated rates of both cardiac (50%) and neurologic (40%) complications, frequently resulting in permanent sequelae. Notably, mycotic aneurysms complicate approximately 25% of R. dentocariosa endocarditis cases, a significantly higher incidence compared to the general IE population (3-5%). Given the paucity of R. dentocariosa endocarditis cases, no standardized antimicrobial protocol exists, necessitating close collaboration with infectious disease specialists. Furthermore, our case was complicated by enlargement of intracranial mycotic aneurysm and severe mitral regurgitation, requiring precise coordination with surgeon regarding optimal surgical timing.
Conclusions: This case exemplifies R. dentocariosa endocarditis complicated by mycotic aneurysm formation, underscoring the criticality of multidisciplinary management through coordinated efforts among neurosurgery, cardiovascular surgery, and infectious disease specialties.