CH12. Giant Cell Arteritis Flashcards
Which arteries are affected in GCA? (size)
Medium and large-size arteries
Year of life where GCA is common?
70s-80s
Is GCA more common in males or females?
Females (65-75%)
What is the description of the pathology of GCA?
Granulomatous inflammation within the vessel wall of medium and large arteries
+
focal and segmental pattern
Which arteries are affected by GCA?
Branches of aorta
External carotid
Ophthalmic arteries
Posterior ciliary arteries
Because of the vessel wall inflammation, ___.
there is disruption of the internal elastic lamina, intimal hyperplasia, and narrowing and obliteration of the vascular lumen.
Two distinct cell lineages are found within the walls. What are they?
TH1 and TH17
(as demonstrated by IFN gamma and IFN 17)
but TH1 is the predominant population
Common symptom of GCA?
Headache, sometimes accompanied by scalp tenderness
Pathomechanism of jaw claudiication?
Due to the inflammation of the facial branches of the external carotid
Differential diagnosis for jaw claudication?
temporomandibular arthropathy
Most dreaded complication of GCA?
Permanent loss of vision
AION vs PION, which is more commmon?
AION is more common (due to affectation of posterior ciliary branches of ophthalmic artery)
PION- hypoperfusion of pial vascular plexus
Risk of ischemic stroke in patients with GCA?
2.2x mostly affects the vertebrobasilar circulation
Does GCA affect intracranial arteries?
Very rare! Usually the extradural segments are affected.
What protein is increased in GCA?
Elastin in the adventitial tissue
Paradoxically, this has been found to be protective against GCA.
Anemia, maybe due to increased tissue angiogenesis
Other manifestations of GCA?
Scalp necrosis
Tongue claudication
Limb ischemia
Mesenteric ischemia
Pericardial effusion
Respiratory symptoms
Aortic vessel disease
SIADH
What is the definitive diagnosis of GCA?
Temporal arterial biopsy
American College of Rheumatology classification criteria for GCA (5)?
- age of onset > 50 years
- new headache
- tenderness on palpation/ pulsation unrelated to arteriosclerosis
- elevated ESR (>=50mm/hr)
- TAB: vasculitis with predomiinance of mononuclear-cell infiltrate or granulomatous inflammation
Unlike ESR, this inflammatory marker is not affected by age or hematologic disorders and appear to be more sensitive in the detection of GCA?
CRP
Finding in Color Doppler Ultrasonography in GCA?
Halo sign- hypoechoic rim surrounding the artery
Also known to be most sensitive and specific finding on ultrasonography
PET/CT imaging finding in GCA?
Increased due to metabolically active inflammatory cells within GCA
To increase the yield of TAB, how long should the artery segments be?
1.5- 2cm long
