Granulomatous angiitis: Difference between revisions
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* A few areas of ischemia may be noticed distal to segment involved. | * A few areas of ischemia may be noticed distal to segment involved. | ||
====Biopsy==== | ====Biopsy==== | ||
* Cerebral biopsy is not routinely done. | |||
* It has low diagnostic accuracy may be due to | |||
** Segmental nature of the lesion in the cerebral vessels | |||
** Rarity of lesion | |||
** Lack of supporting strong radiologic findings. | |||
==Treatment== | ==Treatment== | ||
Revision as of 12:00, 10 August 2012
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Granulomatous angiitis is an uncommon necrotising vasculitis of unknown cause restricted to vessels of the central nervous system.[1]
Historical Perspective
Cravioto and Feigin defined granulomatous angiitis in 1959.
Pathophysiology
The pathophysiologic effect of granulomatous angiitis seems to be altered permeability of the vessel wall. This leads to leaking of cells and proteins into the surrounding structures causing subsequent edema.
Microscopic Pathology
- It mainly involves small intracerebral vessels.
- Microscopic changes include
- Focal fibrinoid necrosis of the vessel wall
- Variable inflammatory infiltrate(neutrophils, lymphocytes, epitheloid appearing histiocytes and multinucleated giant cells) forming granuloma in the wall of the vessel.
- Ischemic or hemorrhagic changes may be seen in parenchyma distal to the segment involved.
Causes
Exact etiology is obscure. Few associations are established.
Differentiating Granulomatous Angiitis from other Diseases
A few vasculitides have to be differentiated from granulomatous angiitis.
- Periarteritis nodosa
- Takayasu disease
- Temporal arteritis
- Sarcoidosis
- Allergic granulomatous arteritis
Distinguishing features include
- Perivascular chronic inflammatory cells
- Presence of fibrinoid necrosis around the intracerebral vessels
- Allergic arteritis is excluded by absence of history of atopy and eosinophillia
- Localization only to intracerebral vessels excludes systemic disease like sarcoidosis
Epidemiology and Demographics
Very few cases of angiitis are reported.
Age
- This is more common in middle aged and elderly individuals.
Gender
- Gender is not associated with increased risk of angiitis.
Race
- Race is not associated with increased risk of angiitis.
Natural History, Complications and Prognosis
The clinical course is usually progressive with occasional temporary remissions. It progresses to death within a year.
Diagnosis
History
- History of Herpes zoster infection
- History of any lymphomas like Hodgkin lymphoma
Symptoms
- Confusion
- Focal cerebral symptoms
Physical Examination
Neurologic
- Altered consciousness
- Unexplained fall
- Intellectual deterioration
Laboratory Findings
Blood and Biomarker Studies
- Complete blood count, differential count to rule out infections.
- Levels of calcium , magnesium and glucose to differentiate from metabolic causes of confusion/encephalopathy.
- Elevated levels of ESR , CRP can be noticed.
CT Scan
- CT scan head may show a few features of difffuse, bilateral, poorly defined , non contrasting low density areas.
- These finding are highly suggestive of granulomatous angiitis .
- Cerebral edema may be evident.
- A few areas of ischemia may be noticed distal to segment involved.
Biopsy
- Cerebral biopsy is not routinely done.
- It has low diagnostic accuracy may be due to
- Segmental nature of the lesion in the cerebral vessels
- Rarity of lesion
- Lack of supporting strong radiologic findings.