Week 2- approach to the investigation of lymphadenopathy Flashcards
What can cause lymphadenopathy?
Viral- e.g. EBV Bacterial Lymphoma Malignancy- particularly metastatic spread. Connective tissue disorders e.g. SLE.
Put the list of differential diagnosis for lymphadenopathy in order from most likely to least likely?
Reactive Bacterial infection (local) Viral infection (generalised) Metastatic malignancy Lymphoma
What causes tender lymphadenopathy?
Viral and bacterial causes.
What causes hard lymph nodes?
Viral, bacterial and metastatic carcinoma
What causes rubbery lymph nodes?
Lymphoma
What causes the surface of the lymph node to be smooth/
Viral, bacterial and lymphoma.
When would the skin become inflamed in lymphadenopathy?
In a bacterial infection
When would the skin be tethered in lymphadenopathy?
Could be tethered in bacterial infection but also likely to be metastatic carcinoma.
What should you do if lymphoma or other malignancies are suspected?
Ask surgeon to biopsy.
How do you assess lymph node pathology?
Histology- microscopic appearance Immunohistochemistry solid node Immunophenotyping blood/marrow Genetic analysis Molecular analysis
What is immunohistochemistry used for?
Confirming its a lymphoma and classifying it.
What does immunohistochemistry do?
Looks at patterns of proteins on the surface of lymphoma cells. Uses antibodies against these to look for reactions. If it turns brown then it is positive.
What is CD20 found in?
Non-Hodgkins lymphoma
B cell lymphomas
What is CD30 found in?
Hodgkins disease.
Describe the process of immunophenotyping?
Cells are tagged with antibodies attached to a fluorochrome molecule. It emits a certain colour when a laser is shone on it if it binds to an antigen.