A 40-year-old man with AIDS and CD4 count below 100 cells/mm3 develops insidious slowing of thought, apathy, psychomotor retardation, and impaired concentration over months. MRI shows bilateral periventricular white matter hyperintensities without cortical atrophy. Memory and language functions are relatively spared. This pattern of cognitive impairment is best described as:

• A Cortical dementia resembling Alzheimer's disease
• B Major neurocognitive disorder due to prion disease
• C Amnestic disorder due to another medical condition
• D Subcortical dementia with prominent psychomotor slowing ✓

Explanation

HIV-associated neurocognitive disorder is the prototype of a subcortical dementia: prominent psychomotor slowing, apathy, and executive and attentional deficits with relative preservation of language and explicit memory until late stages. Cortical dementias such as Alzheimer's show early amnesia, aphasia, and apraxia, which distinguishes them from this patient's profile. White matter involvement on MRI reflects direct viral infection of microglia and macrophages.

Reference: Kaplan and Sadock's Synopsis of Psychiatry, 12th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.