Flashcards in CHAPTER 7: VASCULAR PATHOLOGY Deck (127):
What is the definition of vasculitis?
Inflammation of the blood vessel wall
What are the three layers of an artery?
Adventitia= connective tissue
What is the etiology of vasculitis?
Unknown--most are NOT INFECTIOUS
Generally, what are the symptoms associated with vasculitis?
1) Non-specific sx. of inflammation (fever, fatigue, weight loss, myalgia)
2) Sx. of ORGAN SPECIFIC ischemia
What causes the organ specific ischemia seen in vasculitis?
- Luminal narrowing
- Thrombosis of inflamed vessels
What does large vessel vasculitis involve?
Aorta and its major branches
What does medium vessel vasculitis involve?
Muscular arteries and organs supplied by those arteries
What does small vessel vasculitis involve?
Arterioles, capillaries, venules
What type of vasculitis is Temproal (Giant Cell) Arteritis?
What is Temporal Arteritis?
Granulomatous vasculitis that involves the BRANCHES OF THE CAROTID ARTERY
- Temporal a.
- Ophthalmic a.
What is the typical patient affected by Temporal Arteritis?
- Older adult (greater than 50 y/o)
How does Temporal Arteritis present?
1) Headache= temporal a. involvement
2) Visual disturbances= ophthalmic a. involvement
3) Jaw claudication
What lab is often elevated with Temporal Arteritis?
What will biopsy reveal in Temporal Arteritis?
- Inflamed vessel wall w/ Giant Cell (muli-nucleated large cells)
- Lesions are SEGMENTAL
****B/c lesions are segmental, must biopsy a large segment AND negative biopsy does NOT r/o disease*****
How is Temporal Arteritis treated?
Why is prompt treatment of Temporal Arteritis crucial?
Untreated there is a high risk of blindness
What is Takayasu Arteritis?
Granulomatous vasculitis that involves the AORTIC ARCH at branch points
How does Takayasu Arteritis clinically differ from Temporal Arteritis?
1) Patients are LESS than 50 y/o
How does Takayasu Arteritis present?
Young asian female with:
1) Visual disturbances/ neurologic sx.
2) Weak/ absent upper extremity pulses
What clinical aspects of Takayasu Arteritis and Temporal Arteritis are shared?
- Treatment= corticosteroids for both
- ESR elevation is common to both
What type of vasculitis is Polyarteritis Nodosa?
What is Polyarteritis Nodosa?
Necrotizing vasculitis involving multiple organs, BUT NOT THE LUNGS
How does Polyarteritis Nodosa classically present?
Young adult with:
1) HTN (renal a. involvement)
2) Abdominal pain and melena (mesenteric a. involvement)
3) Neurologic disturbances
4) Skin lesions
What serum maker is associated with Polyarteritis Nodosa?
HBsAg (HBV surface antigen)
Describe the appearance of early lesions in Polyarteritis Nodosa.
Describe the appearance of late lesions in Polyarteritis Nodosa.
How will Polyarteritis Nodosa appear on imaging?
"String of pearls"
- Inflammation leads to weakening of the vessel and "ballooning"
- Fibrosis causes contracture of vessel
- Alternating pattern looks like a pearl necklace
How is Polyarteritis Nodosa treated?
What is Kawasaki Disease?
Medium vessel vasculitis that classically effects CHILDREN
What arteries are commonly involved in Kawasaki Disease?
How does Kawasaki Disease present?
Asian child less than 4 y/o with:
- Erythematous rash on palms and soles
- Cervical lymphadenopathy
What does coronary a. involvement in Kawasaki Disease lead to?
****This is a condition that will cause a MI in a child*****
How is Kawasaki Disease treated?
1) ASPIRIN-- seems odd b/c ASA is contraindicated in kids with an apparent viral illness (Reye Syndrome)
What is Buerger Disease?
Medium vessel, necrotizing vasculitis involving the digits
What is Buerger Disease associated with?
SMOKING--smoking cessation= remission
How does Buerger Disease present?
Ulceration, gangrene, and autoamputation of fingers and toes
What is Wegner Granulomatosis?
Small vessel, necrotizing granulomatous vasculitis involving:
What is the classic presentation of Wegner Granulomatosis?
Middle aged male with:
- Sinusitis/ nasopharyngeal ulceration
- bilateral nodular infiltrates
What serum marker is associated with Wegner Granulomatosis?
How is Wegner Granulomatosis treated?
Cyclophosphamide and steroids
What is Microscopic Polyangiitis?
Small vessel, necrotizing vasculitis involving lung and kidney
How does Microscopic Polyangiitis differ from Wegner Granulomatosis?
NO nasopharyngeal involvement
What serum marker is associated with Microscopic Polyangiitis?
How is Microscopic Polyangiitis treated?
Corticosteroids and cyclophosphamide
What is Churg-Strauss Syndrome?
Small vessel, necrotizing granulomatous inflammation involving the heart and lungs
What serum marker is associated with Churg-Strauss Syndrome? How does this correlate with disease severity?
*Direct correlation between p-ANCA levels and severity of disease*
How does Churg-Strauss Syndrome differ from Microscopic Polyangiitis?
1) Presence of granulomas
2) Asthma often present
3) Eosinophilia often present
What is Henoch-Schonlein Purpura?
Small vessel vasculitis due to IgA immune complex deposotion
What is unique about Henoch-Schonlein Purpura?
Most common vasculitis in children
How does Henoch-Schonlein Purpura present?
- Palpable purpura on buttocks and legs
- GI pain and bleeding
****Usually all following a URI*
What causes the hematuria seen in Henoch-Schonlein Purpura?
How is Henoch-Schonlein Purpura treated?
Typically it is self-limited but severe cases are treated with steroids
What is the classic blood pressure that defines HTN?
*Note the either the systolic or diastolic has to be elevated for the diagnosis, BOTH not required
What are the two broad categories of HTN?
Primary and secondary
What is primary HTN?
HTN of unknown etiology (most common)
List the risk factors associated with primary HTN.
Race (African American)
High Na+ diet
What is secondary HTN?
HTN due to a known cause
What is the most common cause of secondary HTN?
Renal artery stenosis
Describe the stenosis of the renal artery increases blood pressure.
1) Stenosis= decreased blood flow to glomerulus
2) Juxtaglomerular apparatus (JGA) responds by secreting renin
3) Renin= Angiotensinogen--> Angiotensin I
4) ACE= Angiotensin I-->Angiotension II
ATII increases blood pressure
How does angiotensin II increased blood pressure?
1) Contraction of arteriolar smooth muscle= increased TPR
2) Increases Aldosterone secretion from adrenal cortex
How does Aldosterone increase blood pressure?
- Increased Na+ reabsorption in the renal DCT
- Water follows Na+ to increase plasma volume
What are the unique features of renal artery stenosis causing HTN?
1) Increases plasma renin w/ HTN (normally, would be low)
2) Unilateral atrophy of the affected kidney
What are the two most common causes of renal artery stenosis? What patient populations are these most common in?
1) Atherosclerosis (elderly males most commonly)
2) Fibromusuclar dysplasia (young females)
What is Fibromuscular dysplasia?
Developmental defect of the BV wall resulting in an irregular thickening (esp. affecting the renal a.)
What is benign HTN?
HTN seen in most individuals
- Clinically silent
- Vessels/ organs damaged slowly over time
What is malignant HTN?
Acute and severe elevation in BP that presents with end-organ damage
What organs are classically affected by malignant HTN/ what are the signs of malignant HTN?
1) Acute renal failure
****This is a medical emergency****
What is the definition of arteriosclerosis?
"Hard arteries" caused by thickening of the BV wall
What is atherosclerosis?
Specifically refers to intimal plaque formation in medium-sized vessels that obstructs blood flow
Describe the composition of an intimal plaque seen in atherosclerosis.
- Necrotic lipid (cholesterol) core
- Fibromusuclar cap
- Undergoes dystrophic calcification
What vessels are specifically affected by atherosclerosis?
1) Abdominal aorta
2) Coronary arteries
3) Popliteal arteries
4) Internal carotids
What are the modifiable risk factors for atherosclerosis?
What are the non-modifiable risk factors for athersclerosis?
2) Gender (males and postmenopausal females)
Describe the pathogenesis of atherosclerosis.
1) Damage to the endothelium allows lipids to leak into the tunica intima
2) Lipids are oxidized and consumed by macrophages-->"foam cells"
3) Inflammation and healing leads to deposition of ECM and proliferation of smooth muscle
What are the morphologic stages of atherosclerosis?
1) Fatty streak
2) Atherosclerotic plaque
How much stenosis is required before clinically manifestations of atherosclerosis are seen?
What are the four broad complications of atherosclerosis?
1) Stenosis of medium-sized vessels/ ischemia of supplied organs
2) Plaque rupture with thrombosis
3) Plaque rupture with embolism
What are the common manifestations of medium vessel stenosis seen in atherosclerosis?
- Ischemic bowel disease
What are the two most common outcomes of atherosclerotic plaque rupture and thrombosis?
- CVA (ischemic)
How can you identify an atherosclerotic plaque emboli?
Cholesterol crystals that look like spikes
Why does atherosclerosis lead to BV weakening and aneurysm?
- Plaque prevent oxygen diffusion through vessel wall
- Hypoxi/ ischemia= weakness
What is arteriolosclerosis?
Narrowing of the small ARTERIOLES
What are the two types of arteriolosclerosis?
What is hyaline arteriolosclerosis?
Proteins leaking into arteriole wall producing vascular thickening
How does hyaline arteriolosclerosis appear on microscopy?
What usually causes hyaline arteriolosclerosis?
1) Benign HTN
What is the typical consequence of hyaline arteriolosclerosis?
- Reduced vessel caliber with end-organ damage
- Typically the KIDNEY
- Progressive to chronic renal failure
What is hyperplastic ateriolosclerosis?
Thickening of the arteriole wall by hyperplasia of smooth muscle
What typically causes hyperplastic arteriolosclerosis?
*Think of this as the vessel thickening to retain all the blood that is being pushed out*
What is the typical consequence of hyperplastic arteriosclerosis?
- Reduced vessel caliber with end organ damage
- Causes ACUTE renal failure
How is the gross appearance of a failed kidney from hyperplastic arteriolosclerosis described?
What is Monckeberg Medial Calcific Sclerosis?
Calcification of the tunica MEDIA in medium sized arteries
What is unique about Monckeberg Calcific Sclerosis?
NON-OBSTRUCTIVE i.e. not clinically significant
Where are you most likely to encounter Monckeberg Calcific Sclerosis?
Incidental finding on a mammogram
What is an aortic dissection?
Intimal tear with disscetion of blood through the tunica media
Where does aortic dissection typically occur? Why?
Proximal 10cm of the aorta b/c of thickened diffusion barrier
What two things are required for an aortic dissection?
1) High stress
2) Weakness of the tunica media
What causes weakness of the tunica media?
2) Inherited connective tissue defects
How does HTN lead to weakness of the tunica media?
- HTN--> hyaline arteriolosclerosis
- hyaline arteriolosclerosis effects the VASA VASORUM
- Limited blood flow/ ischemia of vessel wall
What are the two inherited connective tissue defects that lead to aortic aneurysm?
1) Marfan's (Fibrillin mutation)
2) Ehler's Danlos Syndrome (Collagen mutation)
How does an aortic dissection present?
Sharp, tearing chest pain that radiates to the back
What are the major complications of an aortic dissection?
1) Pericardial tamponade
2) Fatal hemorrhage
3) Obstruction of branching arteries
How does an aortic dissection cause a pericardial tamponade?
Dissection "back" into the heart causes blood to fill the pericardial sac
What is the most common cause of death from aortic dissection?
What is a thoracic aneurysm?
Balloon-like dilation of the thoracic aorta
What classically causes throacic aneurysms?
- Endarteritis of the vasa vasorum
- Luminal narrow
How is the gross morphology of the aorta described in a patient with tertiary syphilis?
What is the major complication of a thoracic aneurysm?
- Proximal aneurysm causing dilation of the aortic valve
- Causes aortic valve insufficiency
What are some of the more minor complications of a thoracic aneurysm?
1) Compression of mediastinal structures
2) Thrombosis/ embolism
*Aneurysm causes a disruption of normal laminar flow, which inappropriately activates the coagulation cascade.
What is an abdominal aortic aneurysm? Where is this seen?
- Balloon-like dilation of the abdominal aorta
- BELOW the renal arteries but ABOVE the common iliac a.
What is the primary cause of an AAA?
*Increases the diffusion barrier leading to weakness and atrophy of the BV wall
What is the classic patient with an AAA?
- Older than 60
How does an AAA present?
Pulsatile abdominal mass that grows with time
What is the major complication of an AAA?
How does a ruptured AAA present?
2) Pulsatile abdominal mass
3) Flank pain
What is a hemangioma?
Benign tumor of blood vessels
What is the common presentation for a hemangioma?
Seen in kids:
- Present at birth
- Regresses during childhood
What areas are most affected by hemangiomas in kids?
Skin and liver
What is an angiosarcoma?
Malignant proliferation of endothelial cells
What are the common sites affected by angiosarcomas?
What three things are liver angiosarcomas associated with?
What is Kaposi Sarcoma?
Low-grade malignant proliferation of endothelial cells associated with HHV-8 viral infection
How does Kaposi Sarcoma present?
Purple plaques, patches, and nodules on the skin
*May also involve visceral organs
What three patients is Kaposi sarcoma classically seen in?
1) Older Eastern European males
How do you treat Kaposi Sarcoma in older Eastern European males?
How do you treat Kaposi Sarcoma in AIDS patients?