When Do Ring-Enhancing Brain Lesions Need to Be Biopsied, and Should They Be Treated Empirically First?

Other than acute cerebrovascular accidents, multiple ring-enhancing lesions are among the most common lesions encountered in neuroimaging. We herein describe the case of a 63-year-old diabetic man presenting with altered mental status, hyperglycaemia and community-acquired pneumonia who was found to have two ring-enhancing lesions involving the left frontal lobe and left basal ganglia. The lesions were biopsied to reveal positive fungal cultures and toxoplasma cysts. RPR titres returned reactive for non-treponemal antibodies and a suppressed CD4 count was found without evidence of HIV infection.

An approach is discussed that will direct clinicians to decide whether to treat ring-enhancing brain lesions empirically or biopsy them first.