The Lymphoid System

Question 1

Where would you find haematopoietic stem cells in a) the fetus and b) post natal

Answer 1

a) in the foetal liver

b) post natal bone marrow

Question 2

Where do B cells mature

Answer 2

Bone marrow

Question 3

Where do T cells mature

Answer 3

Thymus

Question 4

What are the central (primary) lymphoid tissues?

Answer 4

• bone marrow

- thymus

Question 5

What are the peripheral (seconday) lymphoid tissues?

Answer 5

• LYMPH NODES
• SPLEEN
• Tonsils (waldeyer’s ring)
• Epitheliolymphoid tissue
• Bone marrow

Question 6

How does lymph reach the venous system?

Answer 6

Drains at the junction of the L or R subclavian and jugular veins

Question 7

Where is lymph filtered in the lymph nodes?

Answer 7

Filtered in the parenchyma

Question 8

What are the functions of the lymphatic system

Answer 8

1) to return lymph to the circulation

2) filter lymph before return to the circulation

Question 9

Name a major group of lymph nodes that could be viewed radiologically

Answer 9

E.g mediastinum, para-aortic

Question 10

What is lymphangitis?

Answer 10

Inflammtion of the walls of the lymph vessels

n.b. - in cases of superficial infection, may see red lines extending from an inflamed lesion - lymphangitis

Question 11

What is superficial lymphadenopathy often the first sign of?

Answer 11

Superficial lymphadenopathy may be the first sign of underlying malignancy

Question 12

What does generalised lymphadenopathy suggest?

Answer 12

Suggests a systemic inflammatory process or widespread malignancy

-if malignancy, lymphoma/leukaemia are high in the differential diagnosis –> check FBC !!! a biopsy may not be necessary !!!