Diagnostic Considerations
Regional lymphadenitis
In a patient with regional lymphadenitis, knowledge of lymphatic drainage patterns and pathologic processes most likely to affect these areas can facilitate diagnostic investigation. [4]
Cervical lymph nodes
Cervical lymph nodes receive lymphatic drainage from the head, neck, and oropharyngeal cavities.
Infections associated with cervical lymph nodes are as follows [5] :
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Skin and soft tissue infections of the face
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Dental abscesses
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Otitis externa
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Bacterial pharyngitis
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Cytomegalovirus
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Adenovirus infection
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Rubella
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Toxoplasmosis
Malignancies associated with cervical lymph nodes are as follows:
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Hodgkin lymphoma
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Non-Hodgkin lymphomas
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Squamous cell carcinomas of nasopharyngeal or laryngeal structures
Axillary lymph nodes
Axillary lymph nodes receive lymphatic drainage from upper extremities and breasts.
Infections associated with axillary lymph nodes are as follows:
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B henselae infection (catscratch disease)
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Sporotrichosis
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Tularemia
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Staphylococcal or streptococcal skin infections
Malignancies associated with axillary lymph nodes are as follows:
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Lymphoma
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Melanoma
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Carcinoma of the breast
Epitrochlear lymph nodes
Epitrochlear lymph nodes receive lymphatic drainage from the hands.
Infections associated with epitrochlear lymph nodes are as follows:
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Skin and soft tissue infections from local trauma
Malignancies associated with epitrochlear lymph nodes are as follows:
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Lymphoma
Supraclavicular lymph nodes
Supraclavicular lymph nodes receive lymphatic drainage from the chest and mediastinum.
Infections associated with supraclavicular lymph nodes are as follows:
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Intrathoracic mycobacterial, fungal infections (not bacterial pneumonias or bronchial infections)
Malignancies associated with supraclavicular lymph nodes are as follows (Note: supraclavicular lymphadenitis is an ominous sign of malignancy):
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Intrathoracic and intra-abdominal malignancies (Note: left-sided supraclavicular sentinel node or the Virchow node is highly suggestive of an occult abdominal neoplasm.)
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Breast cancer
Other diseases associated with supraclavicular lymph nodes are as follows:
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Sarcoidosis
Inguinal lymph nodes
Inguinal lymph nodes receive lymphatic drainage from the lower extremities and skin of the lower abdomen, genitals, and perineum. [6]
Infections associated with inguinal lymph nodes are as follows:
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Cellulitis of the lower extremities
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Venereal infections - Syphilis, chancroid, herpes simplex virus infection, lymphogranuloma venereum
Malignancies associated with inguinal lymph nodes are as follows:
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Lymphomas
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Metastatic melanomas from lower extremity primary site
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Squamous cell carcinomas from genital primary site
Note: lymphatic drainage from internal pelvic organs and testes drain via iliac nodes into the para-aortic chain. Therefore, deep pelvic infections or malignancies do not present as inguinal lymphadenitis.
Hilar or mediastinal lymph nodes
Hilar or mediastinal lymph nodes receive lymph drainage from local structures and are usually found on radiologic examination.
Infections associated with hilar or mediastinal lymph nodes are as follows:
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Tuberculosis
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Fungal infections
Malignancies associated with hilar or mediastinal lymph nodes are as follows:
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Bronchogenic carcinoma
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Lymphoma
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Hodgkin lymphoma
Other diseases associated with hilar or mediastinal lymph nodes are as follows:
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Sarcoidosis
Intra-abdominal or retroperitoneal lymph nodes
Intra-abdominal or retroperitoneal lymph nodes receive lymph drainage from local structures, these are typically detected by finding a palpable mass on physical examination or by obstructive/pressure effects on surrounding structures.
Infections associated with intra-abdominal or retroperitoneal lymph nodes are as follows:
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Tuberculosis [7]
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Y enterocolitica infection
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Deep abscess
Malignancies associated with intra-abdominal or retroperitoneal lymph nodes are as follows:
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Hodgkin lymphoma (pelvic and retroperitoneal nodes)
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Non-Hodgkin lymphoma (mesenteric nodes)
Generalized lymphadenitis
In a patient with generalized lymphadenitis, the differential includes systemic conditions.
Associated medication toxicities are as follows:
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Hydralazine
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Allopurinol
Associated infections are as follows:
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Epstein-Barr virus infection
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Cytomegalovirus infection
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Toxoplasmosis
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HIV disease
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Tuberculosis (advanced)
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Histoplasmosis
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Coccidioidomycosis
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Brucellosis
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Bacterial endocarditis
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Hepatitis
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Syphilis (secondary)
Associated immunologic diseases are as follows:
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Sarcoidosis
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Rheumatoid arthritis
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Lupus
Associated malignancies are as follows:
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Acute lymphoblastic leukemia
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Chronic lymphocytic leukemia
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Lymphomas
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Angiofollicular lymph node hyperplasia (Castleman disease)
Differential Diagnoses
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Brucellosis
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Tularemia
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Yersinia Enterocolitica Infection
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A lymph node biopsy is performed. Note that a marking pen has been used to outline the node before removal and that a silk suture has been used to provide traction to assist the removal.