Lymphadenopathy can occur through several mechanisms: replication of nodal cells in response to antigens or malignancy, infiltration of reactive cells from outside the node, deposition of foreign material, or vascular engorgement and edema from cytokine release. Lymphadenopathy can be generalized, involving three or more noncontiguous areas, or localized. Common causes include infectious agents like viruses, bacteria, fungi, and parasites; immunologic diseases; hematologic malignancies; lipid storage diseases; and other disorders such as sarcoidosis and Kawasaki disease. A thorough medical history and physical exam are important to narrow the differential diagnosis.

1. LYMPHADENOPATHY
-ETIOLOGY

2. Lymphadenopathy -
pathophysiology
 Lymph node enlargement may occur via any of the following mechanisms:
 Nodal cells may replicate in response to antigenic stimulation or malignant
transformation (e.g., lymphoma).
 Large number of reactive cells from outside node (e.g., neutrophils or metastatic cells)
may enter node.
 Foreign material may be deposited into node by lipid-laden histiocytes (e.g., lipid
storage diseases).
 Vascular engorgement and edema may occur secondary to local cytokine release.
 Suppuration secondary to tissue necrosis (e.g., Mycobacterium tuberculosis)

3. Clinically 2 types
 Generalised and
 Localised

4. Generalized adenopathy has been
defined as
 involvement of three or more
noncontiguous lymph node areas.
 generalized lymphadenopathy is frequently
associated with nonmalignant disorders

5. 1.Common infectious causes:
Bacterial
 Group A streptococcus
 Mycobacteria: typical and atypical
 Anaerobic bacteria
 Diphtheria
 Brucellosis
 Actinomycetes
 Gram –ve enterios

6. Common infectious causes:
Viral
 Epstein-Barr virus
 Herpes simplex
 Measles
 Mumps
 Coxsackie
 Adenovirus
 HIV
 Rubella

7. Common infectious causes:
Fungal / *Parasitic
 Aspergillosis
 Candida
 Cryptococcus
 Histoplasmosis
 Coccidioidomycosis
 Sporotrichosis
 Blastomycosis
 Toxoplasmosis*

8. 2.Immunologic diseases.
a. Rheumatoid arthritis
b. Juvenile rheumatoid arthritis
c. Mixed connective tissue disease
d. Systemic lupus erythematosus
e. Dermatomyositis
f. Sjögren’s syndrome
g. Serum sickness

9. h. Drug hypersensitivity
i. Primary biliary cirrhosis
j. Graft-versus-host disease
k. Silicone-associated

10. a. Hematologic—Hodgkin’s disease, non-
Hodgkin’s lymphomas, acute or
chronic lymphocytic leukemia, hairy cell
leukemia, malignant histiocytosis,
b. Metastatic—from numerous primary
sites

11. 4. Lipid storage diseases—
Gaucher’s, Niemann-Pick
5. Endocrine diseases—hyperthyroidism

12. 6. Other disorders
a. Castleman’s disease (giant lymph node
hyperplasia)
b. Sarcoidosis
c. Dermatopathic lymphadenitis
d.Histiocytic necrotizing lymphadenitis
e. Sinus histiocytosis with massive lymphadenopathy
f. Mucocutaneous lymph node syndrome (Kawasaki’s
disease

13. g. Familial Mediterranean fever
h. Severe hypertriglyceridemia
i. Vascular transformation of
sinuses
j. Inflammatory pseudotumor of
lymph node

14. Few causes of large nodes
 Lymphangitis
 Acute
 Suppurative-staphylococci most common cause-mode is firm and tender,
erythematous and swollen
 Cat Scratch- most common cause, node lasting longer than 3 wks. Found in
any nodes, large, red, tender
 Hodgkin- malignant nodes matted, firm, rubbery, asymmetry is the rule
 Non-Hodgkin-malignant-well defined and solid, nontender
 Lymphadenitis – node it’s self is infected- one node enlarged, red ,
warm, tender- no streaking

15. Mimicking Lymphadenopathy:
 Branchial cleft cyst
 Cystic hygroma
 Thyroglossal duct cyst
 Epidermoid cyst
 Sternocleidomastoid tumor

16. Mimicking Lymphadenopathy:
 Branchial cleft cyst
 Cystic hygroma
 Thyroglossal duct cyst
 Epidermoid cyst
 Sternocleidomastoid tumor

17.  The causes of lymphadenopathy is broad. A patient's
medical history and review of systems is important in
narrowing this differential. Upon
examination, recognizing the pattern of lymph
drainage aids in seeking an infectious focus.

18. THANK YOU!!!!