A 48-year-old male patient:
* HIV (+)
* Presented to emergency with headache, confusion, N/V
What do you see?
Small corticomedullary hyperintense lesions (a-c) with faint enhancement (d-e)
Toxoplasmosis
* Most common opportunistic CNS infection and most common cause of a mass lesion in AIDS
* Basal ganglia, thalamus, corticomedullary junction and cerebellum frequently involved
* Microhemorrhages can be seen on SWI; lesions may have ring or nodular enhancement
* Major ddx is lymphoma
– Lymphoma is usually solitary, whereas solitary lesions are uncommon in toxoplasmosis
– Microhemorrhages are uncommon in lymphoma

