Diagnosis
Tests
- Ring enhancing lesions (and CD4< 200) on CT suggest lymphoma, Toxo, tuberculoma (developing countries); Multiple lesions favors Toxo
- Non-enhancing lesions (and CD4 < 200), consider: PML, HIV encephalopathy, CMV encephalitis
- MRI can be very helpful, though harder to obtain acutely
- Serum Toxo IgG helpful if negative (Toxo much less likely); Serum CrAg, VDRL
- LP (if safe): cell count, glucose, protein, gram stain, cultures (bacterial, AFB, fungal), PCR (JC virus, toxoplasmosis, HSV, VZV, EBV, CMV), VDRL (syphillis), CrAg (cryptococcus), India Ink (crypto), and cytology (lymphoma)
Related Links