Lymph Node, Lymphadenitis part 2

Lymphadenitis

This is the inflammation of the lymph nodes. This can be classified into the following types :

1. Acute Lymphadenitis:

• · Specific
• · Non-specific

2. Chronic Lymphadenitis:

• · Specific
• · Non-Specific

Acute Lymphadenitis (Specific). This may be :

1. Localized e.g. Regional Lymph Node in appendicitis and tonsillitis extremities infection.
2.  Generalized e.g In Viraemia, Bacteraemia (More common in children) 

Acute Lymphadenitis (Non-Specific)

Acute lymphadenitis may be due to the Common Organism like Staph, which leads to localized abscess. Streptococci leads to cellulites.

Other causes are Typhoid bacilli.

Acute Suppurative Lymphadenitis

sign and symptoms are :

1. Lymph nodes are tender and hot.
2. Microscopically there are mainly polys in the germinal centers.
3. Pyogenic Bacteria present in the germinal center and this are may undergo necrosis.
4. Histiocytes may contains Particulate of bacteria.
5. Ultimately there is resolution.

 Result of acute lymphadenitis

1. Resolution. 
2. Abscess and draining sinuses formation.
3. Scarring.

Chronic Lymphadenitis (Non-specific) classified into:

1. B-Cell Hyperplasia (Follicular hyperplasia)
2. T-Cell or Paracortical Hyperplasia
3. Sinus Histiocytosis.

 B-Cell Hyperplasia (Hyperplastic lymphadenitis)

This is  due to infections by Microbes.

Causes of B-cell hyperplasia:

1. Secondary Syphilis
2. Toxoplasmosis
3. Rheumatoid Arthritis
4. AIDS.

Microscopic appearance of B-cell hyperplasia:

1. Germinal centers are enlarged.
2. Enlarged Lymph node and with presence of various stages of “Blast” transform.

D/D of B-cell hyperplasia from Follicular Lymph node:

1. Blast cells and histiocytes  in Germinal center.
2. There is Phagocytic activity
3. There is presence of polys, monocytes, and eosinophils in parafollicular area.
4. Mitosis in germinal center are seen.
5. There is Variation in Nodule Size.
6. Monomorphic cells in NHL.

Findings	B-Hyperplasia	Follicular lymphoma
Blast cells and histiocytes in germinal center	present	Not prominent
Phagocytic activity	present	not seen
Presence of polys, monocytes, eosinophils	present	monotonous population
Mitosis in germinal center	present	usually absent
Size of nodule	variable	uniform

Paracortical Hyperplasia (T-cell Hyperplasia)

There is predominantly hyperplasia of T cells. The T-Cell change may encroach B-cell area.

Signs and symptoms:

1. Skin rashes and enlarged lymph nodes.
2. There is Fever and enlarged Liver and Spleen.
3. Patient may have Painful Joints.

Causes:

1. Drugs
2. Dilantin Na
3. S.Pox Vaccination
4. Immunological disorder

Microscopic appearance:

1. There is proliferation of T-Lymphocytes and  Immunoblastic cells.
2. ay see polys, eosinophils and macrophages.
3. Hypertrophy of sinusoids and vascular endothelial cells seen , this is  also called Pseudolymphomatous Pattern.

Sinus Histiocytosis (Sinus Hyperplasia)

1. There is distension and prominics of Lymph sinusoids.
2. This is  Seen in lymph node draining Carcinoma of Breast.
3. When present in carcinoma of breast is sign of favorable prognosis.

Chronically  increased Lymph nodes are not tender and their common site is axilla and inguinal area.

Specific Chronic Lymphadenitis

May be seen in –

1. Tuberculosis.
2. Brucellosis.
3. L.venereum.
4. Sarcoidosis
5. Histoplasmosis

Findings	Tuberculosis	Sarcoidosis
Granuloma	soft	hard
Mantoux test	positive	negative
Kveim test	negative	positive
AFB stain	positive	negative

Noncaseating granuloma may be seen in:

1. Some patients with Hodgkin’s disease.
2. Crohn’s disease.
3. Syphilis.

Immunoblastic Lymphadenitis

This condition also called Angioimmunoblastic lymphadenopathy.

It resemble clinically like Hodgkin disease and needs to differentiate histologically from it.

Signs and symptoms

1. There may be fever.
2. Patient may have sweating.
3. There are skin rashes.
4. There is generalized enlargement of the lymph nodes.
5. There is enlarged liver and spleen.
6. patient may history of autoimmune disease.
7. Sometime may see autoimmune hemolytic anemia.
8. There is polyclonal hypergammaglobulinemia.

Microscopic appearance

1. There are small arborizing blood vessels with prominent endothelial cells.
2. There are numerous immunoblastic cells and plasma cells.
3. There is deposition of eosinophilic PAS positive material.
4. There are occasional epithelial cells.

Outcome of the disease

1. The patient may have a aplastic anemia.
2. The patient may develop Lymphoma.
3. Bone marrow show Lennert’s lymphoma (in 70% ) of the cases.

Angiofollicular Hyperplasia 

This is also called Castleman’s disease, Giant lymph node hyperplasia and Benign giant lymphoma.

Its etiology is unknown.

Signs and symptoms

1. Usually there is presentation of mediastinal mass.
2. There is fatigue, night sweating, nausea and weight loss. 
3. There may be anemia and fever.
4. there may be flu like symptoms.
5. There is enlargement of the lymph nodes.
6. There is hyperglobulinemia.

Microscopic appearance

There are following variant of this condition:

1. Hyaline- vascular type
2. Plasma cell type
3. Mixed type 
4. Plasmablastic type

Differential diagnosis

• In case of mediastinal mass needs to differentiate from lymphoma.

• From Kaposi sarcoma.

Lymphangiopathic Histiocytosis

This is also called Rosai-Dorfman disease. Also called as sinus histiocytosis with massive lymphadenopathy.

This is chronic disease and unknown etiology.

Age: This is mainly seen in children and young adults.

Signs and symptoms

1. There is massive increase in the size of lymph nodes.
2. There may be fever.

Microscopic appearance

1. There is Increase in histiocytes in sinusoids.
2. Occasional Mononuclear giant cells are seen.
3. Follicular centers are absent.
4. Increase plasma cells seen in the medullary cards.
5. Capsular and Pericapsular inflammation and fibrosis are common.

Outcome

1. This may subside.
2. In some cases may lead to death.

Dermatopathic Lymphadenopathy

It is also called lipo melanotic Reticulosis.

This is seen in chronic inflammation or destructive (Exfoliative) lesion of the skin.

Microscope appearance:

1. It is characterized by widened pale staining paracortical area  (T-lymphocyte Zone).
2. There are Foamy, vacuolated macrophages.
3. Some of the macrophage contains melanin and hemosiderin.
4. There is Increase in Eosinophils, plasma  cells and immunoblastic cells.

Necrotizing Lymphadenitis

1. This is Seen in:
1. Lupus erythematosus.
2. Bubonic Plagues.
3. Infectious Mononucleosis.
4. Anthrax.
5. Typhoid.
6. Dilantin sodium  hypersensitivity.

Microscope appearance:

1. There is Extensive Haemorrhage.
2. There is necrosis.
3. This are is surrounded by the histiocytes.

Lymphadenopathy due to AIDS

Characterized by:

1. Marked follicular hyperplasia.
2. Infiltration of follicles by small Lymphocytes.
3. There are  Foci of intra-follicular haemorrhage “follicle lysis”.
4. Focal perisinusoidal or monocytoid B-cell hyperplasia.

There is High incidence of:

1. B-cell Lymphoma.
2. Hodgkin disease.
3. Kaposi sarcoma.

Kikuchi Disease

1. It is also called as Histiocytic Necrotizing Lymphadenopathy.
2. There is unknown etiology.
3. It is more common in young females.
4. Histology: There is  Paracortical Necrosis surrounded by histiocytes.

Idiopathic infraction of Lymph Node

It is seen in Patient with pyrexia of unknown origin (PUO).

                                           Causes of Enlargement of Lymph Node

The causes of enlargement of the lymph node is classified as follows:

1. Localized or generalized

2. Acute:

•  Specific
•  Non-specific

3. Chronic:

•  Specific
•  Non-specific

4. Tumors:

• Primary
• Secondary

5. Pseudolymphomatous  conditions:

• Follicular Hyperplasia.
• Post vaccinal

Causes of enlargement of the lymph nodes

1. Lymphangiopathic histiocytosis (Rosai- Dorfman disease).
2. Angiofollicular hyperplasia (Castleman’s disease, benign giant lymphoma).
3. Immunoblastic lymphadenopathy (Lennert’s Lymphoma).
4. Dermatopathic Lymphadenopathy.
5. Necrotizing lymphadenopathy.
6. AID- lymphadenopathy.
7. Kikuchi disease.
8. Idiopathic infarction of Lymph Node.
9. Cat- scratch disease.