In this week’s Case Record of the Massachusetts General Hospital, a 35-year-old woman with stable HIV infection was admitted to this hospital because of headache and altered mental status. Brain imaging revealed diffuse white-matter abnormalities. A diagnostic test was performed.
HIV infection is associated with a spectrum of syndromes of cognitive dysfunction, which are subsumed under the term HIV-associated neurocognitive disorders. These syndromes range from an asymptomatic neurocognitive disorder to a mild neurocognitive disorder to HIV-associated dementia and are seen in 40 to 60% of people who are infected with HIV.
• What are the characteristics of HIV-associated neurocognitive disorders?
This type of injury is particularly evident in the striatum, hippocampus, and prefrontal cortex and correlates clinically with impairment of abstraction, mental flexibility, attention span, judgment, and psychomotor speed.
• Does antiretroviral treatment effectively prevent HIV-associated neurocognitive disorders?
Patients who are effectively treated with antiretroviral therapy are protected against HIV-associated dementia, but antiretroviral therapy does not seem to prevent asymptomatic or mild neurocognitive disorders, which are probably due to more morphologically subtle, diffuse synaptic and dendritic injury.
Table 3. Differential Diagnosis of White-Matter Disease in a Patient with HIV Infection.
Morning Report Questions
Q: What is HIV-associated leukoencephalopathy?
A: HIV-associated leukoencephalopathy is characterized by profound subcortical dementia and marked diffuse confluent white-matter abnormalities on imaging. This syndrome is probably a fulminant form of HIV-associated dementia and HIV encephalitis that affects the white matter in particular.
Q: What is the immune reconstitution inflammatory syndrome?
A: Immune reconstitution inflammatory syndrome (IRIS) is an appropriate but excessive immune response to an antigenic stimulus, usually infectious in nature, in the context of immune recovery after initiation of antiretroviral therapy. Neurologic presentations of IRIS seem to be much less common than systemic IRIS, with an estimated incidence of less than 1%.