Cerebral amyloid angiopathy

Source: Wikipedia, the free encyclopedia.
Cerebral amyloid angiopathy
Other namesCongophilic angiopathy[1]
Micrograph of cerebral amyloid angiopathy using congo red stain
SpecialtyNeurology Edit this on Wikidata
CausesCause of CAA is unknown[2]
Diagnostic methodPET scan, CT scan[2]
TreatmentManagement can be physical, occupational, or speech therapy.[2]

Cerebral amyloid angiopathy (CAA) is a form of

tissue after staining with Congo red. The amyloid material is only found in the brain and as such the disease is not related to other forms of amyloidosis.[4]

Signs and symptoms

CAA is associated with brain hemorrhages, particularly microhemorrhages. The accumulation of amyloid beta peptide deposits in the blood vessel walls results in damage of the blood vessels and hindrance of normal blood flow, making blood vessels more prone to bleeding

bleeding in the brain).[8] The location of the cerebral microbleed determines whether it is more likely to have been caused by hypertension or CAA. Tsai et al. conducted amyloid PET imaging in an Asian population with cerebral amyloid angiopathy–intracerebral hemorrhage and noticed that superficial cerebellar microbleeds are related to CAA, whereas deep or mixed-location cerebellar microbleeds are more likely related to hypertension.[9]

Causes

Astrocyte

CAA has been identified as occurring either sporadically (generally in elderly populations)

leptomeningeal and cerebral vessel walls.[11] CAA occurring in the Flemish type has been observed to be linked to large dense-core plaques observed in this pedigree.[12]

The reason for increased deposition of Aβ in sporadic CAA is still unclear with both increased production of the peptide and abnormal clearance having been proposed as potential causes.

insulysin (3) cleared by way of the blood–brain barrier or (4) drained along periarterial spaces. Abnormalities in each of these identified clearance pathways have been linked to CAA.[14][15]

In familial forms of CAA, the cause of Aβ build up is likely due to increased production rather than poor clearance.

amyloid precursor protein (APP), Presenilin (PS) 1 and PS2 genes can result in increased rates of cleavage of the APP into Aβ. An immune mechanism has also been proposed.[17][18] apolipoprotein E (APOE) ε2 and ε4 are associated with increased risk of getting cerebral amyloid antipathy. The use of antiplatelet and anticoagulant therapy increases the risk of getting intracerebral haemorrhage in CAA.[19]

Types

Several familial variants exist.[20] The condition is usually associated with amyloid beta.[21] However, there are types involving other amyloid peptides:

  • the "Icelandic type" is associated with cystatin C amyloid (ACys).[22]
  • the "British type" and "Danish type" are associated with British amyloid (ABri) and Danish amyloid (ADan) respectively. Both peptides are linked to mutations in ITM2B.[23]
  • Familial amyloidosis-Finnish type is associated with gelsolin amyloid (AGel).[24]

Pathophysiology

The vascular amyloid pathology characteristic of CAA can be classified as either Type 1 or Type 2, the latter type being the more common. Type 1 CAA pathology entails detectable amyloid deposits within cortical capillaries as well as within the leptomeningeal and cortical arteries and arterioles. In type 2 CAA pathology, amyloid deposits are present in leptomeningeal and cortical arteries and arterioles, but not in capillaries. Deposits in veins or venules are possible in either type but are far less prevalent.[25]

Diagnosis

MRI showing low signal foci in cerebral amyloid angiopathy. Conventional gradient echo T2*-weighted image (left, TE=20ms), susceptibility weighted image (SWI) and SWI phase image (center and right, respectively, TE=40ms) at 1.5 Tesla.[26]

CAA can only be definitively diagnosed by a post-mortem autopsy.[27] Biopsies can play a role in diagnosing probable cases.[28] When no tissue is available for biopsy, the Boston Criteria are used to determine probable CAA cases from MRI or CT scan data. The Boston Criteria require evidence of multiple lobar or cortical hemorrhages to label a patient as probably having CAA.[27] Susceptibility weighted imaging has been proposed as a tool for identifying CAA-related microhemorrhages.[29]

Imaging

Cerebral amyloid angiopathy can be presented with

computed tomography (CT) scan would show hyperdense haemorrhage area and hypodense odema around the haemorrhagic site.[19]

MRI sequence of

gradient echo and susceptibility weighted imaging (SWI) are useful in detecting microbleeds and deposition of iron on the brain cortex (cortical superficial siderosis).[19] Other MRI indicators of CAA include white matter hyperintensities and cortical thinning.[30]

Management

The aim in cerebral amyloid angiopathy is to treat the symptoms, as there is no current cure. Physical, occupational and/or

speech therapy may be helpful in the management of this condition.[2]

History

Gustav Oppenheim was the first to report vascular amyloid β deposits on the vasculature of the central nervous system in 1909. The first paper focusing solely on what would come to be known as CAA was published in 1938 by WZ Scholz. In 1979, H. Okazaki published a paper implicating CAA in certain cases of lobar intracerebral hemorrhage.[24] The Boston Criteria for CAA originated in a 1995 paper from Harvard Medical School.[27]

References

  1. PMID 16627535
    .
  2. ^ a b c d e "Cerebral amyloid angiopathy: MedlinePlus Medical Encyclopedia". www.nlm.nih.gov. Retrieved 2015-05-27.
  3. ^ "UpToDate". www.uptodate.com. Retrieved 2019-08-17.
  4. ISBN 9780199710041.{{cite book}}: CS1 maint: multiple names: authors list (link
    )
  5. ^ "Exploring cerebral amyloid angiopathy: Insights into pathogenesis, diagnosis, and treatment".
  6. ISBN 9781107310896
    .
  7. ISBN 9780080922188
    .
  8. ^ "Brain Basics: Preventing Stroke: National Institute of Neurological Disorders and Stroke (NINDS)". www.ninds.nih.gov. Retrieved 2015-05-27.
  9. PMID 31726962
    . Retrieved 2023-11-17.
  10. ISBN 9780781769471
    .
  11. ISBN 9781107014558
    .
  12. PMID 12163376
    .
  13. ISBN 9781461512493
    .
  14. ISBN 9780323227353
    .
  15. ISBN 9780444634948
    .
  16. ISBN 978-0702054662
    .
  17. ISBN 9781464900853
    .
  18. ISBN 9781464991721
    .
  19. ^
    PMID 29604173
    .
  20. S2CID 8930792
    .
  21. ISBN 9781444341232
    .
  22. ISBN 9780521717922
    .
  23. ISBN 9780199644957
    .
  24. ^
    PMID 21519520
    .
  25. PMID 11895043
    .
  26. PMID 19131406
    .
  27. ^
    PMID 29335334
    .
  28. ISBN 9789401710077
    .
  29. ISBN 978-1437707014
    .
  30. PMID 28334869
    .

Further reading

External links

Scholia has a topic profile for Cerebral amyloid angiopathy.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Cerebral_amyloid_angiopathy&oldid=1195332419"