Vasculitis Flashcards
Define vasculitis
Vasculitis is inflammation of blood vessels, often with ischemia, necrosis, and organ inflammation. It cause vessel destruction (aneurysm/rupture), or stenosis.
It can affect any blood vessel—arteries, arterioles, veins, venules, or capillaries.
Clinical manifestations of are diverse and depend on the size and location of the involved vessels and the degree of the organ dysfunction and inflammation.
What can causes of vasculitis be split into?
Primary vasculitis - resulting from an inflammatory response that targets the vessel walls and has no known cause; sometimes this is autoimmune
Secondary vasculitis may be triggered by an infection, a drug, or a toxin or may occur as part of another inflammatory disorder or cancer
Pathogenesis of vasculitis?
A trigger causes T cells to over excite, releasing cytokines and promoting inflammation. This results in collection of macrophages called granulomas. Over time this damages the vessel wall, which starts to thicken and become irregular, causing clots to form on the vessel, which can break off and cause ischaemia.
What are the three types of vasculitis?
Give an example of each.
Classification is by the size of the vessel:
- Large: giant cell arteritis, Takayasu’s arteritis
- Medium: polyarteritis nodosa, Kawasaki disease
- Small: GPA, EGPA, MPA
What symptoms should make you think of vasculitis?
Consider vasculitis in any unidentified multisystem disorder; if presentation doesn’t fit clinically or serologically into a specific category, then consider malignancy-associated vasculitis.
What are the two main types of large cell vasculitis?
How does the epidemiology differ between them?
What are both characterized by in terms of pathology?
The two main causes of large vessel vasculitis are Takayasu arteritis (TA) and Giant Cell arteritis (GCA).
TA predominantly affects those under 40 years and is commoner in females. It is much more prevalent in Asian populations.
GCA generally affects those over 50 years. It typically causes temporal arteritis but the aorta and other large vessels may be affected.
Both conditions are characterised by granulomatous infiltration of the walls of the large vessels – this shows up on biopsy which can confirm the diagnosis.
What type of symptoms tend to occur in large cell vasculitis?
Claudication type symptoms can occur, e.g. aching/pain after walking for a while etc.
Patients also have systemic symptoms e.g. fatigue, weight loss.
What are some presenting features of large cell vasculitis?
Bruit, with the most common location being the carotid artery (80%) – this is due to vessel narrowing
Blood pressure difference of extremities (45%-69%) – caused by stenosis of the vessel
Claudication (38%-81%)
Carotodynia or vessel tenderness on palpitation (13%-32%)
Hypertension (28%-53%)
Temporal arteritis
What muscle condition is it associated with?
What are the classic symptoms?
What is there a risk of?
The association with polymyalgia rheumatica is well recognized: about 50% with GCA have PMR, and about 15% of individuals with PMR develop GCA
Classic symptoms include unilateral temporal headache, scalp tenderness and jaw claudication (claudication definition = aching of a muscle that comes on with repeated use)
The temporal arteries may be prominent with reduced pulsation
There is a risk of blindness due to ischaemia of the optic nerve
What investigations would you do for large vessel arteritis and what would they show?
ESR, plasma viscosity and CRP are raised
If symptoms of temporal arteritis then a temporal artery biopsy may be helpful (remember that “skip lesions” occur so biopsy may be negative)
A negative biopsy does not mean the patient definitely doesn’t have the condition
Imaging such as MR angiogram or PET CT may show vessel wall thickening/stenosis/anuerysm or increased metabolic activity
How is large cell arteritis managed?
The mainstay of treatment is steroids with a starting dose of 40-60mg prednisolone
Steroid sparing agents such as methotrexate or azathioprine may be considered – this is if patient is struggling to reduce their steroid dose over time
40 mg prednisolone if no visual problems
If they do have visual involvement, then 60 mg prednisolone
Medium cell vasculitis
What are the two main types and what are the differences between them?
Kawasaki disease is seen in children, usually under 5 years. It can cause vasculitis of various vessels but the most important are the coronary arteries, where aneurysms can develop.
Polyarteritis nodosa is characterized by necrotizing inflammatory lesions that affect arteries at vessel bifurcations, resulting in microaneurysm formation and aneurysms leads to infarction in affected organisms.
- It often affects the skin, gut and kidneys – it is hard to diagnose because lots of organ involvement.
- It is associated with patients who have chronic hepatitis B infection.
What are the two main classifications of small cell vasculitis?
They tend to be divided into ANCA associated vasculitis (AAV) and those where ANCA is usually negative.
ANCA-associated is the most common one to be seen in rheumatology.
What are the three main conditions that come under small cell vasculitis?
Briefly describe each
GPA - There is granulomatous inflammation of the vessels in the respiratory tract, small and medium vessels, necrotising glomerulonephritis is common.
EGPA – characterized by eosinophilic granulomatous inflammation of the respiratory tract, small and medium vessels and is associated with asthma.
MPA – necrotising vasculitis with few immune deposits - this affects kidneys, and sometimes lungs, but doesn’t have the multisystem presentation that the other two do.
GPA
Where is it more common?
Male:female ratio?
Individuals of northern european descent
1.5:1
