What is the most commonly documented mechanism for aortic dissection?
A child dies suddenly at night. Autopsy shows massive endothelial inflammation and desquamation of the skin. What type of hypersensitivity caused this child's death?
Type II. In Kawasaki, anti-endothelial antibodies bind directly to the endothelium and cause damage.
What type of arteriosclerosis is localized to the tunica media and may show calcifications?
A 55-year-old male stockbroker presents with a blood pressure of 165/90. The patient has a 2-year history of urinary frequency, especially at night, and has been told his blood pressure was “borderline” for many years. He has a 60 pack year smoking history, and consumes 2-3 alcoholic drinks per day. He has elevated CRP and cholesterol levels. What can this patient alter to extend his life expectancy?
Alter cholesterol, sodium intake, smoking, lose weight.
What is the most common cause of essential hypertension?
95% of essential hypertension cases are of unknown etiology.
What are the two main factors contributing to hypertension?
Cardiac output and vascular resistance.
Why does kidney failure cause hypertension?
Decreased perfusion to the kidneys results in increased angiotensin II (vasoconstricts and stimulates release of aldosterone)
How does hypertension cause arteriolar thickening as seen here? How does this affect the kidneys?
Hyaline arteriolosclerosis. The high pressure causes tissue injury and pushes serum proteins into the vessel walls. This can lead to kidney failure from decreased serum protein levels.
What type of hypertension is the image seen associated with?
Malignant hypertension. Note hyperplastic arteriosclerosis (onion skinning)
What causes the damage seen here?
Retinopathy. Arterioles and blood supply in the retina thicken and narrow. Also note yellow exudates from vascular leakage.
A 73-year-old retired USAF male pilot is noted to have a pulsatile mass within the abdomen on physical exam by the second year medical student. The patient has a 4-year history of urinary frequency, especially at night. He has been treated intermittently for high blood pressure for the past 12 years. He has an 80 pack year smoking history and reports to be a social drinker. He is a barrel chested male with soft abdomen, 5 cm diameter pulsatile mass palpated below the umbilicus. BP 165/90. Where in his body is the pathology most likely to be? Why is he barrel chested and why does he pee a lot?
Abdominal aortic aneurism. Between the renal artery and above the femoral bifurcation. He is an old smoker so he is barrel chested from emphysema and pees a lot because he probably has an enlarged prostate.
What is seen here?
Early plaque. 1) Fibrous cap 2) lipid center.
What is this person at high risk for?
This is an advanced atheromatus plaque causing fissures and degeneration. You are at high risk for thrombus development and atheroembolism because of the extensive plaques.
What is indicated by the arrow?
When do you get nervous about this rupturing?
5cm. Mortality is 50% if it ruptures before surgery.
Why do you get thrombi in aneurisms?
Turbulent and static flow
A 56-year-old man experienced the sudden onset of excruciating chest pain, which moved progressively downward. The patient was rushed to the emergency room. He was taken to aortic angiography where a type II dissection was documented and then immediately to the operating room. Hypertension treated with diuretics. His vital signs included pulse of 102, blood pressure 172/140 mm/Hg, respirations of 22/minute and a temperature 37.2. Angiography reveals a type II dissection. Why is there such high mortality if you do not treat this man?
Hemorrhage and occlusion of nearby arteries as the aorta expands causing ischemia.
What happens in the event of an ascending aortic dissection?
It messes up the aortic valve and causes massive regurgitation.
What type of aortic dissections are most fatal?
Type A. This is where coronary arteries can be compressed and aortic valve destruction can occur.
What is the underlying cause of dissections?
Cystic media necrosis (loss of elastic fibers)
A 64 year old male, complains of fever and feeling tired for the past week, severe headache for the past 2 days, now presents to ER with 2 hour history of double vision. He currently volunteers at WRB, had a heart attack 7 months ago, and was hospitalized for 1 week. His mother died age 60 Breast cancer; Father died from a MI at the age of 60. He has marked tenderness to palpation of lateral forehead and temples. What do you expect to see in this patient's labs?
This patient has temporal arteritis. It is the most common vasculitis in the elderly. Since it is an inflammatory condition, you would see elevated CRP due to giant cell and granuloma formation in the vessel wall.
What hypersensitivities are often seen in systemic vasculitis?
Type II direct antibody, Type III immune complexes and Type IV granulomatous.
What symptoms do people with a systemic vasculitis normally prevent with?
Constitutional symptoms. Outside of that, the inflammation of the vessel can cause ischemia and infarction.
The family baby-sitter found a 2-month-old male infant unresponsive in his crib lying in a prone position. The infant was brought to the hospital where he was pronounced dead. The infant had been born at 38 weeks gestation and weighed 3200g. An autopsy was performed. Toxicology was negative. Police investigation did not identify any foul play. What are the key associated symptoms in diagnosing this condition?
This is Kawasaki syndrome. You have focal localization in the coronary arteries, strawberry tongue (oropharyngeal inflammation), enlarged cervical lymph nodes, desquamatous rash, bilateral conjuctivitis, and erythema on palms and soles of feet.
A thin 32 year old male with AIDS with purple lesions on his legs. Ancillary Studies: HIV positive, T-cell count markedly reduced. What might he have if his condition is malignant? Intermediate-grade? Benign? Reactive?
Malignant = angiosarcoma. Intermediate = Kaposi sarcoma. Benign = hemangiomas. Reactive = bacillary (infection from Bartonella) angiomatosis
What microbe causes Kaposi sarcoma?
How would this look grossly?
Notice bartonella rods in silver stain. This is bacillary angiomatosis.
What markers tell you that this tumor is actually an angiosarcoma?
CD-31 and vWF