48-year-old male patient, HIV (+); presented to emergency with headache, confusion, N/V.
What do you see?
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T2 hyperintense lesions of left caudate nucleus, left putaminal and right dentate nucleus , with perilesional edema.
Small corticomedullary T2 hyperintense lesions with faint enhancement.
Caudate and putaminal lesions demonstrates faint peripheric contrast enhancement whereas cerebeller lesion has strong peripheric and central nodular enhancement.
Caudate and cerebellar lesion have tiny microhemorrhages on SWI, a clue for diagnosis.
· 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