有許多的疾病均能引起頭暈等中樞神經系統缺損症狀，舉凡是腦梗塞、腦出血、腦炎、梅尼爾氏症，甚至免疫系統異常或惡性腫瘤，而其診斷上賴於影像學判斷是不足的。本案例是一位33歲男性病人，因為頭暈三週，在入院前三日發生單側肢體無力而入院，經腦部影像檢查及詳細的接觸史詢問後，因高度懷疑免疫功能低下引起的腦弓漿蟲感染並先予預防性用藥，緊接著在確診新型冠狀病毒及感染人類免疫缺乏病毒並接受治療後，中樞神經系統缺損症狀獲得改善而順利出院。當臨床上遇到中樞神經系統缺損症狀的年輕壯年男子，由於腦弓漿蟲感染在神經系統表現之頭暈較無特異性，除了影像學診斷之外，在病史的詢問更應詳盡，針對免疫系統可能受損的病患，詳細了解感染風險與接觸史，或許其中能有些提示能夠協助我們早期辨別如腦弓漿蟲等特異感染引起的中樞神經症狀而能即早診斷與治療。

A variety of diseases-including cerebral infarction, hemorrhage, encephalitis, Meniere’s disease, im-mune abnormalities and malignancies-can cause central nervous system (CNS) deficits such as dizzi-ness. However, relying solely on neuroimaging for diagnosis may be insufficient. This case report de-scribes a 33-year-old male who presented with three weeks of dizziness, followed by unilateral limb weakness three days prior to admission. Brain imaging, combined with a detailed exposure history, raised strong suspicion of cerebral toxoplasmosis secondary to immunosuppression. Empiric treatment was initiated, and subsequent testing confirmed co-infection with SARS-CoV-2 and human immuno-deficiency virus (HIV). The patient responded well to treatment, with resolution of CNS symptoms, and was discharged in stable condition. This case highlights the importance of thorough history-tak-ing—particularly regarding immune status, infection risks, and potential exposures—when evaluating young adults with non-specific CNS symptoms such as dizziness. In such patients, opportunistic infec-tions like cerebral toxoplasmosis should be considered early, especially when immune compromise is suspected, to facilitate timely diagnosis and treatment.