Enlarged lymph nodes (generally larger than 1 cm). for inguinal, its larger than 1.5 cm. for epitrochlear (located above the elbow cease on the medial side), its larger than .5 cm.
How do lymph nodes get enlarged?
3 main ways:
1) reactive hyperplasia (cells in the lymph node react to an antigen / inflammation)
2) cells in the lymph node transform
3) malignant cells invade the lymph node
History:
- 2 main types of lymphadenopathy: regional and generalized
- if regional: ask about regional symptoms (ex: cervical –> any pharyngeal symptoms, dental problems, hoarseness?)
- if generalized: could be a number of things (infection, immunologic, metabolic, malignant); is often associated with splenomegaly
- fever, weight loss –> cancer, systemic infection, connective tissue disease
- rashes, arthralgias, pharyngeal symptoms, pet exposure –> connective tissue disease, viral illness, cat scratch fever
- contact with sheep –> brucellosis
- location –> coccidioidomycosis (west texas, desert west), histoplasmosis (mississippi river valley)
- animal bites –> Franciesella tularensis (rabbits), Pasteurella (domestic pet bites).
Physical Exam:
- malignant: hard, fixed, nontender, greater than 3 cm
- infectious: warm, erythematous, fluctuant
- reactive: discrete, rubbery, mobile
- red streaks from an inflammed node –> lyphangitis and lymphadenitis
Diagnosing:
- most are self-limited / benign
- can do monospot or strep screen to start, CBC, serology
- if supraclavicular –> can be serious and may need to do a biopsy
- supraclavicular or pulmonary symptoms –> chest xray
- various titers: EBV, toxoplasomosis, CMV,
- other serologic tests: HIV antibodies, ANA, rheumatoid factor
- inguinal: can do urethral or cervical cultures
- unusual cases (bites): blood cultures
- US, CT, MRI can be done later on to delineate involved area
- anemia, thrombocytopenia, malignant cells on peripheral smear –> bone marrow examination
Treatment:
- Cat scratch: TMP/SMX
- Atypical mycobacteria: surgical excision + antituberculosis meds (Isoniazid, Rifampin, ethambutol)
- Lymphadenitis: treat with antibiotics that take care of strep and staph (Cephalosporin, Erythromycin, Dicloxacillin)