Lymphadinitis

Question 1

Lynph nodes discrete encapsulated structures, are formed of?

Answer 1

-Cortex (made of primary (inactive) and secondary (active) follicles
-Paracortical area (in between and inner to follicles)
-Medulla is towards inside, formed mainly of vascular sinusoids and multiple cells

Question 2

Cortex, paracortical area, medulla contains what?

Answer 2

Cortex: Lymphoid follicles contain mainly B lymphocytes
Paracortical rea: contain mainly T lymphocytes
medulla: formed mainly of vascular sinusoids and multiple cells (T lymphocytes, plasma cells and macrophages)

Question 3

Acute Nonspecific Lymphadenitis cause?

Answer 3

Lymph nodes undergo reactive changes by microbiologic agents or foreign matter introduced into wounds
may be isolated or be generalized

Question 4

Acute Nonspecific Lymphadenitis Grossly is seen as?

Answer 4

nodes become swollen, red, tender, overlying skin is red, abscess may develop

Question 5

Acute Nonspecific Lymphadenitis microscopically is seen as?

Answer 5

lymphoid follicles have large germinal centers containing numerous mitotic figures To form plasma which produces AB
When the cause is a pyogenic organism, neutrophils are seen around the follicles and within the lymphoid sinuses. the centers of follicles can undergo necrosis

Question 6

Fate of Acute Nonspecific Lymphadenitis

Answer 6

Either
- revert to normal
- undergo abcess/necrosis/scarring

Question 7

Chronia Nonspecific Lymphadenitis Depending on the causative agent, can assume one of three patterns, name them!

Answer 7

• Follicular hyperplasia
• Paracortical hyperplasia
• Sinus histiocytosis

Question 8

Chronia Nonspecific Lymphadenitis grossly?

Answer 8

LN are enlarged, non tender with no signs of acute inflammation

Question 9

Follicular hyperplasia (Reactive hyperplasia) caused by?

Answer 9

stimuli that activate humoral immunity (antibody response)causing B cell proliferation, which migrate in to follicles creating the follicular reaction

Question 10

Example for a stimuli that causes follicular hyperplasia?

Answer 10

rheumatoid arthritis, toxoplasmosis

Question 11

follicular hyperplasia microscopically is seen as?

Answer 11

show multiple, variable sized, large lymphoid follicles which has wide germinal centers surrounded by a collar of small mature B lymphocytes

Question 12

What is the collar of small mature B lymphocytes
Surrounding the lymphoid follicle called?

Answer 12

Mantle zone

Question 13

Follicular hyperplasia germinal centre contain?

Answer 13

proliferating B cells tingible body macrophages blue arrow, and a meshwork of antigen-presenting follicular dendritic cells

Question 14

Paracortical hyperplasia cause?

Answer 14

caused by immune reactions involving the T cell regions of the lymph node.
When activated, parafollicular T cells transform into large proliferating immunoblasts that encroach on the B cell follicles.

Question 15

Paracortical hyperplasia examples?

Answer 15

In viral infection, vaccinations, drugs

Question 16

Sinus histocytosis is characterized by?

Answer 16

distention of the lymphatic sinusoids

Question 17

Sinus histocytosis microscopic picture?

Answer 17

distention of the lymphatic sinusoids, owing to a marked hypertrophy of lining endothelial cells and an infiltrate of macrophages (histiocytes)

Question 18

Sinus histocytes is often encountered in lymph nodes draining ….?

Answer 18

encountered in lymph nodes draining cancers and may represent an immune response to the tumor or its products

Question 19

Chronic specific lymphadenitis all types

Answer 19

• TB
• Sarcoidosis
• Syphilis
• Toxoplasmosis
• Brucellosis

Question 20

Define TB

Answer 20

Chronic infection leads to caseous necrosis (cheese like necrotic tissue)

Question 21

A granuloma caused by T.B infection is formed of What?

Answer 21

epithelioid macrophages surrounded by a collar of lymphocytes & multinucleated giant cells, undergoes central zone of necrosis (caseous necrosis)

Question 22

Kikuchi-Fujimoto disease (KFD) etiology?

Answer 22

necrotizing lymphadenitis Of unknown etiology ,prevalent in Asia (Mostly Japan).

Question 23

KFD clinically show as?

Answer 23

persistently enlarged cervical lymph nodes unresponsive to antibiotic therapy ,predominantly in young females

Question 24

KFD microscopic pic

Answer 24

The lymph node show an area of necrosis surrounded by collar of lymphocytes, macrophages (histiocytes)

Question 25

KFD fate

Answer 25

self-limiting disease, resolves spontaneously in several weeks

Question 26

Cat-Scratch Disease etiology

Answer 26

self-limited lymphadenitis caused by the bacterium Bartonella henselae

Question 27

Cat-Scratch Disease clinically?

Answer 27

manifests with regional lymphadenopathy, most frequently in the axilla and the neck. The nodal enlargement appears approximately 2 weeks after a cat scratch

Question 28

Cat-Scratch Disease morph

Answer 28

central necrosis associated with an infiltrate of neutrophils forming irregular stellate necrotizing areas microbe is extracellular and can be visualized with silver stains.

Question 29

Cat-Scratch Disease fate

Answer 29

lymph node enlargement regresses during a period of 2 to 4 months. Rarely, encephalitis, osteomyelitis develop in patients:

Question 30

Cat-Scratch Disease diagnosis

Answer 30

based on a history of exposure to cats, the characteristic clinical findings, a positive serologic testing for antibodies to Bartonella, and the distinctive morphologic changes in the lymph nodes.