Differential Diagnosis for Young Patient with Altered Mental Status and Parieto-Temporal Hyperdense Lesion on CT Brain
- Single Most Likely Diagnosis
- A. Herpes Encephalitis: This is the most likely diagnosis due to the location of the lesion (parieto-temporal) which is typical for herpes simplex encephalitis, a condition known to cause altered mental status and have a predilection for the temporal lobes.
- Other Likely Diagnoses
- B. Meningoencephalitis: Infections that cause meningoencephalitis can present with altered mental status and may show areas of hyperdensity on CT due to inflammation or edema, though the pattern might be more diffuse.
- C. Brain Abscess: While less common than herpes encephalitis in the context provided, a brain abscess could present as a hyperdense lesion, especially if it is encapsulated and contains pus, which could appear hyperdense on CT.
- Do Not Miss Diagnoses
- Hemorrhagic Stroke: Although the question suggests a hyperdense lesion which could imply a hemorrhage, the clinical context (altered mental status, young patient) and the specific location (parieto-temporal) might not be as typical for a primary hemorrhagic stroke. However, it's crucial not to miss this diagnosis due to its high morbidity and mortality.
- Cerebral Venous Thrombosis: This condition can cause hyperdense lesions due to thrombosis and subsequent hemorrhage, especially in the venous sinuses or cortical veins, and can present with altered mental status. It's a diagnosis that requires prompt recognition and treatment.
- Rare Diagnoses
- Primary Brain Tumors: While rare in the acute presentation described, certain primary brain tumors (like glioblastoma) could appear as hyperdense lesions on CT, especially if they have hemorrhagic components.
- Cerebral Arteritis: Inflammatory diseases affecting the cerebral arteries, such as giant cell arteritis or primary central nervous system vasculitis, could potentially cause hyperdense lesions due to inflammation or ischemia, though they are less common and might not typically present with such focal lesions in young patients.