Large-vessel vasculitis: Takayasu arteritis, Giant Cell Arteritis Flashcards
Define vasculitis?
Heterogeneous group of conditions characterised by blood vessel wall inflammation
What are the 2 most common pathophysiologies of vasculitis?
Immune-mediated inflammation
Direct vascular pathogenic invasion
Apart from immune inflammation and pathogenic invasion, how can physical and chemical injuries to vessel walls cause vasculitis?
Factors such as mechanical trauma, toxins, radiation
Give the 3 primary ways of classifying vasculitides?
Vessel diameter
Involvement of immune complexes
ANCA-associated or not
Define granulomatous vasculitis?
Pathological process due to the destruction of vessels by a granulomatous infiltrate which contains different immune cell lines
Is Takayasu arteritis a type of granulomatous or non-granulomatous vasculitis?
Granulomatous
Which 3 blood vessels are characteristically inflamed in Takayasu arteritis?
Aorta
Major aortic branches
Medium-sized pulmonary arteries
How does Takayasu arteritis characteristically affect the upper extremities?
Causes weak pulse and bp
Which facial feature does Takayasu arteritis characteristically affect?
Eyes
Causes ocular disturbances
What is the ratio of females to males who develop Takayasu arteritis?
8:1
Much more prevalent in females
Which continent has the highest prevalence and incidence of Takayasu arteritis?
Asia
What is the typical onset age range for Takayasu arteritis?
25-40
In Takayasu arteritis, what is the first stage of progression, and which vessel does it occur in?
Scarring and thickening of aorta, arch branches due to granulomatous inflammation causes significant lumen narrowing
In the pre-pulseless/early symptoms of Takayasu arteritis, are symptoms specific or systemic?
Systemic symptoms
eg. weight loss, arthragia, fever, fatigue, claudication (muscle pain due to lack of oxygen that’s triggered by activity and relieved by rest)
Define claudication, and in which phase of Takayasu arteritis does it occur?
Muscle pain due to lack of oxygen that’s triggered by activity and relieved by rest
Early symptom/pre-pulseless phase
In which phase of Takayasu arteritis do ocular disturbances occur, and give 3 common examples?
Late symptom/pulseless phase
eg. visual field defects, retinal defects, blindness
In which phase of Takayasu arteritis does weak pulse and bp in upper extremities occur?
Late symptoms/pulseless phase
Give 2 common symptoms of pulmonary artery involvement in Takayasu arteritis, and which phase does this occur in?
Pulmonary hypertension
Bruits/vascular murmurs (sound caused by turbulent blood flow of blood in artery, possibly due to partial obstruction)
Occur in late symptoms/pulseless phase
What type of x-ray is done to investigate Takayasu arteritis?
Angiography: X-ray of blood vessels
What is meant by occlusion?
complete/partial blockage of blood vessel
Define aneurysmal dilation, and what is the other name for this?
Aortic root aneurysm
enlargement/bulging near aortic valve due to weakened vessel walls
Define coarctation?
Narrowing in aortic arch
What are the 3 characteristic radiological findings on an angiogram, in Takayasu arteritis?
Coarctation (narrowing in aortic arch)
Aortic root aneurysm (Bulging near aortic valve due to weakened walls)
Occlusion (complete/partial blockage of blood vessel)
What lab test is done to diagnose Takayasu arteritis, and what is the characteristic finding?
FBC
Normocytic normochromic anaemia: Low number of normal-sized (normocytic) and normal red-coloured (normochromic) RBCs
Define normocytic normochromic anaemia?
Low number of normal-sized (normocytic) and normal red-coloured (normochromic) RBCs
How is Takayasu arteritis generally managed?
High-dose glucocorticoids and immunosuppressants
Do people with Takayasu arteritis have a high or low 5-year survival rate?
High (83%)
Are people with Takayasu arteritis likely to make a full recovery in the long-term?
No, they are more likely to have visual, neurological deficits
What are the other 2 names for Giant Cell Arteritis (GCA)?
Temporal arteritis
Cranial arteritis
Is GCA a type of granulomatous or non-granulomatous vasculitis?
Granulomatous
Which arteries are characteristically inflamed in GCA?
Arteries in head, mostly temporal arteries (around temples) and occipital arteries (posterior portion of neck and back of head)
Which other rheumatological condition is GCA commonly associated with?
Polymyalgia rheumatica
Give 2 of the largest risk factors for developing GCA?
Old age
North-European descent
How does age affect risk of developing GCA?
Risk increases with age
How does ethnic descent affect risk of developing GCA?
North-European descent is at higher risk
What is the typical onset age for GCA?
Over 50 yrs old
In GCA presentation, describe the person’s energy level?
Low energy, feel fatigued
In GCA presentation, where does facial pain tend to occur and which 2 movements exacerbate it?
Jaw claudication
Worsened by chewing and talking
In GCA presentation, where are headaches most intense and tender upon palpation and why?
Around temples
Because temporal arteries are there
How does GCA commonly affect the scalp in 3 ways?
Tender scalp
Hair loss
Red, shiny ulcers
How does GCA commonly cause temporal and occipital arteries to look and feel?
Thickened and bulging from skin
Tender, low pulsation
Is GCA due to immune-mediated inflammation or vascular pathogenic invasion?
T-cell mediated immune response to antigen found in vessel wall leads to granulomatous inflammation and high interleukin levels
Which artery is affected in GCA, to cause ocular problems?
Ophthalmic artery
Is vision loss or vision disturbance more common in GCA?
Vision disturbance in 25-50% cases
Vision loss in 6-10% cases
Give 4 examples of ocular problems that occur due to ophthalmic artery involvement in GCA?
Diplopia (double vision)
Visual hallucinations
Temporary monocular blindness
Complete blindness
How does GCA affect the risk of aneurysms, and where are they most likely to occur?
Increases risk of aneurysms
Most likely to be aortic aneurysms
Give 2 ways in which GCA can cause serious heart complications?
Aortic aneurysm
Myocardial infarction
How does GCA affects the risk of strokes?
Increases risk of cerebral vascular accidents (strokes)
What used to be the first-line investigation for diagnosing GCA, and why is it not first-line anymore?
Temporal artery biopsy
Negative biopsy result doesn’t rule out GCA as vascular inflammation is patchy and the non-inflamed tissue area could have been obtained for the sample instead
Why does a single negative temporal artery biopsy not rule out GCA, and how can you be more sure to rule out GCA using this investigation?
Negative biopsy result doesn’t rule out GCA as vascular inflammation is patchy and the non-inflamed tissue area could have been obtained for the sample instead
Should obtain multiple samples to biopsy
What is the current gold-standard for investigating GCA, and what is the characteristic sign?
Ultrasound imaging shows ‘halo’ sign
‘halo’ sign: dark thick border (edema/swelling in thickened vessel wall) surrounding narrowed arterial lumen
When would you use PET scan to investigate GCA, and what is the main disadvantage?
When GCA affects deep vessels
Uses large amount of radiation
Describe the CRP and ESR levels, in GCA?
Elevated
Describe the 2 main findings of a FBC, in GCA?
Elevated platelet count
Normochromic normocytic anaemia
Why is GCA a medical and ophthalmic emergency?
Causes complete blindness (as ophthalmic artery vasculitis can lead to sudden and permanent blindness)
Other life-threatening complications due to occlusion/rupture of arteries
If someone has GCA and suspected blindness, what medication should you prescribe to have an effect within 48-72 hrs, and what is the starting dose?
Prednisolone
60-80 mg (weight-dependent)
In GCA treatment, what should the dose of prednisolone ideally be after 8 weeks of administration?
Should be tapered down from 60-80mg to 10-15mg, after 8 weeks
After the prednisolone dose has been reduced to 10-15 mg, how should it be further tapered and adjusted if there is a flare up, in GCA?
Now rate of reduction should decrease by 1 mg per month, if flare occurs then increase dosage again and try tapering in few weeks time
To treat resistant cases of GCA, what medication is now used and for how long?
Tocilizumab can be used for resistant cases for 12 months
When can bisphosphonates be taken to help treat GCA?
After assessing risk of osteoporosis and vitamin D sufficiency
