Ischemic Stroke Due to Septic Emboli in a 78-Year-Old Man With Portal Vein Thrombosis

The patient was a 78-year-old immunocompetent male, with a known history of hypertension, but no diabetes, arrhythmia, or ischemic stroke. He was admitted to the geriatric medicine department due to abdominal pain and fever for 2 months. Further investigations revealed portal vein thrombosis, and Streptococcus intermedius presented in blood culture. Postadmission, the patient developed dysarthria, dysphagia, and left hemiparesis. An initial brain computed tomography scan showed no hemorrhage, but ischemic stroke was suspected. Cerebrospinal fluid analysis revealed no pleocytosis, with normal glucose and protein levels, and the culture showed no bacterial growth. Subsequent brain magnetic resonance imaging (MRI) with gadolinium contrast revealed multiple cerebral emboli across both hemispheres and the midbrain, each lesion measuring <10 mm with diffusion restriction and mild perifocal edema [Figure 1a and b]. The T1-weighted sequence with contrast displayed a rim-enhancing pattern, indicative of septic emboli with microabscess formation [Figure 1c]. Unlike embolic stroke, septic cerebral emboli tend to show contrast enhancement on brain MRI, with a higher likelihood of perifocal edema and hemorrhagic transformation.Figure 1: The magnetic resonance imaging of the brain: upper row was at the level of medulla oblongata and cerebellum and the lower row was at the level of corona radiata. The diffusion-weighted image (a) showed multiple high signal lesions, with corresponding low signal on apparent diffusion coefficient image (b), which is suggestive of diffusion restriction of the lesions. The T1-weighted image with contrast (c) showed the rim-enhancing pattern of the lesions. Note the enhancing lesion in cerebellum was labeled by arrow.Distinguishing septic cerebral emboli is vital due to different therapeutic approaches. While embolic stroke focuses on restoring blood flow and anticoagulation, septic emboli management involves treating the underlying infection with antibiotics and sometimes surgical removal.[1] Besides, anticoagulants may harm septic cerebral emboli,[2] underscoring the importance of imaging differentiation. An 8-week course of ceftriaxone treatment was initiated for the septic cerebral infarction. During hospitalization, the patient’s neurological symptoms remained stable. A follow-up brain MRI 1 month later showed a reduction in the size and number of lesions, suggesting a positive response to antibiotic therapy. This case underscores the need to consider rare causes in patients with portal vein thrombosis and fever, highlighting the diagnostic value of gadolinium-enhanced MRI in distinguishing between septic and bland emboli, which is crucial for effective clinical management. Ethics statement The study was conducted in accordance with the Declaration of Helsinki and was approved by the IRB of Mackay Memorial Hospital (approval number 23MMHIS295e). The authors certify that they have obtained all appropriate patient consent form. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Data availability statement All relevant data are available within the article. Further data may be provided upon reasonable request to the corresponding author. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.