A Case of Infective Endocarditis Caused by Streptococcus gordonii Complicated with Bacterial Meningitis and Cerebral Infarction —— Application of Metagenomic Next-Generation Sequencing (mNGS)

This study reports a case of infective endocarditis (IE) caused by Streptococcus gordonii . The patient presented with cerebral infarction as the initial manifestation, complicated by bacterial meningitis and mitral regurgitation. The diagnosis of Streptococcus gordonii -induced infective endocarditis was facilitated by metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF). Streptococcus gordonii was detected by CSF mNGS within 40 hours after admission, which was 30 hours earlier than the positive result of blood culture. During anti-infective therapy, the patient experienced recurrent thromboembolic events and underwent emergency mechanical thrombectomy due to occlusion of the left vertebral artery. Despite aggressive treatment, the patient eventually died of heart failure. This case indicates that Streptococcus gordonii is a rare pathogen of infective endocarditis, and its clinical presentation complicated by cerebral infarction and bacterial meningitis is distinctive; particularly, complex cases requiring mechanical thrombectomy are extremely rare in clinical practice. As an important complement to conventional bacterial culture, mNGS can shorten diagnostic delay, especially in patients with negative blood or CSF cultures. For patients with concurrent cerebral infarction and meningitis, the possibility of infective endocarditis should be highly suspected, and indications for valve replacement surgery should be evaluated as early as possible in high-risk cases.