Dual Infection with dengue virus and infective endocarditis leading to brain abscess, multiorgan infarctions, and horner syndrome: a case report with literature review

Abstract Background This case report describes the rare occurrence of co-infection with dengue fever followed by infective endocarditis in a young patient from an endemic area. This infection led to multiple complications, including multiorgan infarctions involving the brain, kidneys, liver, and spleen; septic emboli; brain abscess; and horner’s syndrome. The clinical course, diagnostic challenges, and management are discussed, along with a brief review of the literature addressing the relationship between dengue-related immunosuppression and secondary bacterial infections, which can lead to infective endocarditis and septic emboli, resulting in multiorgan infarctions. Case summary A 17-year-old previously healthy male presented one month after confirmed dengue infection with persistent fever and progressive neurological deterioration. Neuroimaging revealed multiple cerebral infarctions, including hemorrhagic and ischemic events, complicated by a brain abscess. Abdominal imaging demonstrated wedge-shaped infarctions in the kidneys, liver, and spleen, consistent with systemic septic embolization. Echocardiography identified a mobile mitral valve vegetation, establishing the diagnosis of infective endocarditis. Laboratory investigations showed elevated inflammatory markers and positive dengue IgM serology. The patient was managed with prolonged intravenous antibiotic therapy and supportive multidisciplinary care, resulting in radiological and clinical improvement. Conclusion Dengue fever–associated immune dysregulation may predispose patients to secondary bacterial infections, including infective endocarditis. Septic embolization is a well-known complication of IE, but the extent of multiorgan involvement seen in this case is uncommon. Brain abscess secondary to IE is also rare and requires multidisciplinary management.