Blood vessels 2 easy

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Questions and Answers

What is a characteristic finding of classic Kaposi Sarcoma?

Absence of endothelial markers

Presence of erythrocytes

Presence of glomeruli

VEGFR-3 positivity (correct)

Where are cavernous lymphangiomas most commonly located in children?

Back

Upper extremities

Abdomen

Neck or axilla (correct)

What is the composition of the stroma in cavernous lymphangiomas?

Fatty tissue

Muscle fibers

Connective tissue stroma containing lymphoid aggregates (correct)

Dense collagen fibers

Which condition is most commonly associated with AIDS-related Kaposi Sarcoma?

HIV infection Signup and view all the answers

What type of cells primarily make up the nodules in Kaposi Sarcoma?

Plump, proliferating spindle cells Signup and view all the answers

What is the first stage in the morphology of Kaposi Sarcoma?

Patches Signup and view all the answers

What is a major cause of aortic aneurysms associated with systemic hypertension?

Atherosclerosis Signup and view all the answers

Which cells primarily produce MMPs that contribute to the breakdown of the extracellular matrix in inflamed aorta?

Macrophages Signup and view all the answers

What effect does inflammation have on collagen synthesis in the context of cystic medial degeneration?

Alters balance of collagen degradation and synthesis Signup and view all the answers

What role do TIMPs play in the context of MMP production?

They inhibit MMP activity Signup and view all the answers

What is a result of systemic hypertension affecting arterioles of the vasa vasorum?

Outer medial ischemia Signup and view all the answers

Which cytokines are associated with the Th2 response that drives increased MMP production in macrophages?

IL-10 and IL-4 Signup and view all the answers

What type of aneurysm is commonly associated with atherosclerosis and affects the iliac arteries?

Abdominal aortic aneurysms (AAA) Signup and view all the answers

Which condition is associated with obliterative endarteritis impacting vasa vasorum of the thoracic aorta?

Tertiary syphilis Signup and view all the answers

What is a potential origin of mycotic aneurysms?

Embolization of a septic embolus Signup and view all the answers

What is the most common bacterial agent that causes lymphangitis?

Group A streptococcus Signup and view all the answers

Which condition is characterized by a collection of lymph fluid in a body part?

Lymphedema Signup and view all the answers

Which of the following is NOT a cause of secondary lymphedema?

Congenital lymphedema Signup and view all the answers

What is a major risk factor for aortic dissections?

Hypertension Signup and view all the answers

What is a notable symptom of lymphangitis?

Red, painful subcutaneous streaks Signup and view all the answers

What characterizes the morphology of aorta in patients with dissections?

Elastic fiber fragmentation and loss Signup and view all the answers

Which of the following conditions is associated with congenital lymphedema?

Familial Milroy disease Signup and view all the answers

What usually initiates a spontaneous aortic dissection?

Intimal tear Signup and view all the answers

What effect does postradiation fibrosis have on the lymphatic system?

Inhibits lymphatic drainage Signup and view all the answers

What type of pain is associated with classical symptoms of aortic dissection?

Sudden onset excruciating pain in the anterior chest Signup and view all the answers

What is a common complication associated with Sturge-Weber syndrome?

Intellectual disability Signup and view all the answers

What is the most common cause of death in aortic dissections?

Rupture of the dissection Signup and view all the answers

What type of lymphatic disorder is lymphadenitis?

Infection of the lymph nodes Signup and view all the answers

What is a characteristic finding in the aorta of hypertensive patients concerning dissection?

Mucoid ECM accumulation Signup and view all the answers

Which statement accurately describes the histological feature of conditions involving lymphedema?

Thin-walled capillaries with scant stroma Signup and view all the answers

What is the effect of aggressive pressure-reducing therapy in the context of dissections?

It may limit the evolving dissection Signup and view all the answers

Which of the following factors can cause secondary lymphedema?

Tumors Signup and view all the answers

Where do most spontaneous aortic dissections occur?

In the ascending aorta Signup and view all the answers

What is notably absent in the inflammation related to aortic dissections?

Signs of inflammation Signup and view all the answers

What type of signaling defect can lead to aortic dissections?

Defective TGF-B signaling Signup and view all the answers

What type of mutation is primarily associated with port wine stains in Sturge-Weber Syndrome?

Somatic single nucleotide missense mutation in GNAQ Signup and view all the answers

Which statement about juvenile hemangiomas is true?

They commonly completely regress by age 7 in most cases. Signup and view all the answers

Spider telangiectasias are most commonly associated with which condition?

Hyperestrogenic states Signup and view all the answers

What characteristic distinguishes cavernous hemangiomas from capillary hemangiomas?

Cavernous hemangiomas infiltrate deep structures and do not regress spontaneously. Signup and view all the answers

What genetic inheritance pattern does hereditary hemorrhagic telangiectasias follow?

Autosomal dominant Signup and view all the answers

Which of the following is a potential complication of hereditary hemorrhagic telangiectasias?

Epistaxis and GI bleeding Signup and view all the answers

Angiomatosis refers to which of the following?

An extensive and diffuse form of hemangiomas. Signup and view all the answers

Malignant transformation of hemangiomas is:

Very rare. Signup and view all the answers

Which vascular malformation resembles a spider and blanches with pressure?

Spider telangiectasia Signup and view all the answers

Which statement correctly describes juvenile hemangiomas?

They are extremely common and can be multiple. Signup and view all the answers

Study Notes

Cystic Medial Degeneration

TGF-B3 itself can contribute to the degeneration.
Aneurysms in this area are prone to rupture even at small sizes.
Atherosclerosis and hypertension are the most important causes of aortic aneurysms.
Atherosclerosis is most common in abdominal aortic aneurysms (AAA) and common iliac arteries.
Hypertension is most common in ascending aortic aneurysms.
Other factors include advanced age, smoking, trauma, vasculitis, congenital defects, dysplasia and berry aneurysms, infections (mycotic aneurysms).
Mycotic aneurysms can originate from embolization of a septic embolus, extension of an adjacent suppurative process, or circulating organisms directly infecting the arterial wall.

Pathogenesis

The balance of collagen degradation and synthesis is altered by inflammation and associated proteases.
Inflammation or atherosclerosis of the aorta leads to inflammatory cells, mainly macrophages, producing MMPs.
MMPs contribute to the breakdown of extracellular matrix components.
There is also loss of TIMP, tissue inhibitors of metalloproteinases.
This may involve Th2 production of cytokines, like IL-4 and IL-10, which drive macrophages to produce increased amounts of MMPs.
The vascular wall is weakened through loss of smooth muscle cells or the inappropriate synthesis of non-collagenous or non-elastic extracellular matrix (ECM).
Systemic hypertension can significantly narrow the arterioles of the vasa vasorum leading to outer medial ischemia.
Tertiary syphilis can cause obliterative endarteritis in the vasa vasorum of the thoracic aorta, leading to medial ischemia, SMC loss, elastic fiber loss, and inadequate or inappropriate ECM production.
Cystic medial degeneration can be iatrogenic.

Thoracic Aortic Aneurysm

Hypertension is a major risk factor.
Aortas have decreased smooth muscle cell and ECM content.
Medial degenerative changes are seen in hypertensive patients.
Defective TGF-B signaling can also contribute.
Aggressive pressure-reducing therapy may be effective in limiting evolving dissection.

Morphology

Elastic fiber fragmentation and loss is present.
Mucoid ECM accumulation occurs.
There is attrition of smooth muscle cells.
Inflammation is characteristically absent.
Dissections usually start with an intimal tear.
Most spontaneous dissections occur in the ascending aorta.

Classical Symptoms of Dissection

Sudden onset of excruciating pain, usually in the anterior chest, radiating to the back between the scapulae.
Pain may move downwards as dissection progresses.

Rupture

Rupture of the dissection is the most common cause of death.
Rupture can lead to bleeding into the pericardial, pleural, or peritoneal cavities.

Lymphangitis

Acute inflammation of the lymphatics caused by bacterial infection.
Group A streptococcus is the most common agent.
Symptoms include red, painful subcutaneous streaks with painful enlargement of the draining lymph nodes (lymphadenitis).

Lymphedema

Collection of lymph fluid in a body part.
Primary lymphedema can be congenital or familial.
Secondary lymphedema is more common and is caused by tumors, surgical procedures, post-radiation fibrosis, filariasis, post-inflammatory thrombosis, and scarring.

Sturge-Weber Syndrome

If lesions are distributed according to the trigeminal nerve innervation, it is also known as encephalotrgeminal angiomatosis.
Characterized by facial port wine nevi.
Ipsilateral venous angiomas in the cortical leptomeninges are present.
Associated with intellectual disability, seizures, hemiplegia, and skull radiopacities.
Can also occur in the liver, spleen, and kidneys.

Hemangiomas

Tumors composed of blood-filled vessels.
Most are present from birth and initially increase in size, but regress spontaneously.
Angiomatosis is a more extensive and diffuse form of hemangiomas.

Capillary Hemangiomas

Histologically, they are thin-walled capillaries with scant stroma.

Juvenile Hemangiomas

Extremely common and can be multiple.
Completely regress by age 7 in most cases.

Spider Telangiectasias

Nonneoplastic vascular malformations that resemble a spider.
Associated with hyperestrogenic states, such as pregnancy or patients with cirrhosis.

Cavernous Hemangiomas

Large, dilated vascular channels.
More infiltrative and frequently involve deep structures.
Do not spontaneously regress.
Unencapsulated and composed of large, cavernous blood-filled vascular spaces.
Can be seen in von Hippel-Lindau disease.

Hereditary Hemorrhagic Telangiectasias

Also known as Osler-Weber-Rendu disease.
Autosomal dominant inheritance.
Mutations in genes encoding components of the TGF-B signaling pathway of endothelial cells.
Lesions can spontaneously rupture and may lead to serious epistaxis, gastrointestinal bleeding, and hematuria.

Glomus Tumor (Glomangioma)

Exquisitely painful tumors.
Arise from modified smooth muscle cells of the glomus bodies, which are arteriovenous structures involved in thermoregulation.
Commonly found in the distal portion of digits, under the fingernails.
Excision is curative.

Kaposi Sarcoma

Solid, vascular tumors that are almost always benign.
Classified as endothelial tumors by the presence of endothelial markers or the absence of erythrocytes, including VEGFR-3 and LYVE-1.
Can occur in the skin, mouth, lungs, and lymph nodes, and can be acquired or inherited.

Classic KS

Not associated with HIV infection.
Involves multiple red-purple skin plaques or nodules, usually in the distal lower extremities.
Tumors are asymptomatic and remain localized.

Transplant-Associated KS

Occurs in those who have had a solid organ transplant with T-cell immunosuppression.

AIDS-Associated (Epidemic) KS

Most common HIV-related malignancy.
Often involves lymph nodes and disseminates widely to viscera.
Morphology progresses through patches, raised plaques, and nodules.

Patches

Red-purple macules.
Histologically, they show dilated, irregular endothelial cell-lined vascular spaces with interspersed lymphocytes, plasma cells, and macrophages.

Raised Plaques

Dermal accumulations of dilated, jagged vascular channels, lined and surrounded by plump spindle cells.

Nodules

Sheets of plump, proliferating spindle cells, mostly in the dermis or subcutaneous tissues.
This stage often heralds lymph node and visceral involvement.

Cavernous Lymphangiomas (Cystic Hygromas)

Typically on the neck or axilla of children.
Rarely in the retroperitoneum, but when they do occur there, they tend to be large.
Massively dilated lymphatic spaces, lined by endothelial cells and separated by connective tissue stroma containing lymphoid aggregates.
Cavernous lymphangiomas in the neck are common in Turner Syndrome.

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Description

Test your knowledge on cystic medial degeneration and its connection to aortic aneurysms. This quiz covers key factors contributing to degeneration, including TGF-B3, atherosclerosis, and hypertension. Explore the pathogenesis and various factors influencing aneurysm formation.