HIV Encephalopathy-MRI

30 Year old retroviral positive lady presents with altered sensorium and varied neurological signs not specifically localizable. CEMRI suggests bilateral, symmetrical, extensive, ill defined, confluent  restricted diffusion, predominantly white matter lesions including corpus callosum and cerebellar peduncles with relative sparing of the subcortical regions with sparse contrast enhancement with  no significant mass effect, possibly representing HIV Encephalopathy. 

Teaching points by Dr MGK Murthy :

1. Direct involvement by the HIV virus itself is the commonest neurological sequalae of disease.  30 % of HIV positive patients present with encephalopathy. Dementia followed by pyramidal and cerebellar degenerations are usual.
2. Classical appearance of confluent, bilateral and symmetrical white matter lesions seen as diffuse white matter changes in the periventricular region and centrum semiovale, with relative sparing of the subcortical white matter and posterior fossa structures is usual. There is no mass effect / contrast enhancement ordinarily.