Page 63 - The Vasculitides, Volume 1: General Considerations and Systemic Vasculitis

Overview of Primary and Secondary Vasculitides 39

in vasa vasorum. Viral antigen but not leukocytes were found in the media in late VZV
vasculopathy [179].

HIV/AIDS

Early in the HIV/AIDS epidemic, it was clear that a significant proportion of infected
persons were intravenous drug users. Their associated risk behavior exposed them to infection
through sharing of contaminated needles thereby increasing the risk of spread of HIV and
other blood borne infections. The two postulated periods in the neurobiology of HIV when
autoimmune disease manifestations and cerebral vasculitis can occur are shortly after
seroconversion and before the spread of productive infection, and after initiation of highly
active antiretroviral therapy (HAART) in association with the immune reconstitution
inflammatory syndrome (IRIS) [180]. The timing of early HIV invasion has been difficult to
ascertain based on the presence of one or well-recognized clinicopathological HIV/AIDS
syndromes including HIV encephalitis, HIV-associated dementia and AIDS-dementia
complex [181-183], all of which are indicative of symptomatic infection. Headache
associated with irritation and confusion was the presenting feature of a 42-year-old
homosexual man without evidence of immunodeficiency who developed cerebral
granulomatous angiitis in association with human-T-lymphotropic virus type II (HTLV-III).
At postmortem examination there was evidence of fibrous intimal scarring and marked
luminal narrowing of the ACA, MCA and PCA and their proximal branches, with
mononuclear cell infiltration of the vessel walls and numerous multinucleated giant cells near
the internal elastic lamina. Six presymptomatic HIV-seropositive drug abusers by Gray and
colleagues [160] had non-necrotizing cerebral vasculitis at postmortem examination.

Identification of Single Organ Vasculitides

Primary Angiitis of the Central Nervous System

Adult and childhood isolated angiitis or vasculitis are prototypical primary vasculitic
disorders restricted to the CNS. The diagnosis of PACNS [184] like IACNS [185] originally
relied upon classic angiographic (Figure 3) or histopathologic features of angiitis within the
CNS in the absence of systemic vasculitis or another cause for the observed findings. The
typical patient with PACNS presented with headache of gradual onset often accompanied by
the signs and symptoms of dementia, while only later developing focal neurological
symptoms and signs. The clinical course might be rapidly progressive over days to weeks, or
at times insidiously over many months with seemingly prolonged periods of stabilization.
Those with the subset of granulomatous angiitis of the brain (GAB) [186] presented with
headache, mental change, and elevated CSF protein content with or without pleocytosis.
Hemiparesis, quadriparesis, and lethargy were associated with a poor prognosis and mandated
the need for combined meningeal and brain biopsy to establish the diagnosis with certainty.
Granulomatous giant cell and epithelioid cell infiltration in the walls of arteries of various

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