HIV-associated opportunistic CNS infections: pathophysiology, diagnosis and treatment

Opportunistic infections of the CNS, such as cryptococcal meningitis, cerebral toxoplasmosis, and tuberculous meningitis, are a major cause of morbidity and mortality in HIV-positive individualsCerebral toxoplasmosis should be suspected in patients with AIDS who present with movement disorders; progressive multifocal leukoencephalopathy (PML) should be suspected in those patients with AIDS who present with cortical blindnessCerebrospinal fluid sample analyses can facilitate diagnosis of PML, cryptococcal or tuberculous meningitis and cytomegalovirus encephalitisA definitive diagnosis of cerebral toxoplasmosis requires a combination of serological testing, MRI findings, and in certain cases, brain biopsyOn MRI, toxoplasmosis often manifests with several brain abscesses with predilection for the basal ganglia, whereas PML typically manifests as diffuse white matter lesions with predilection for the subcortical U fibresIn patients with HIV or AIDS, treatment with antiretroviral drugs in the setting of opportunistic infections can lead to a paradoxical worsening of symptoms, caused by immune reconstitution inflammatory syndrome