Secondary Lymphoid Tissues ›› Lymph Node ›› Non-neoplastic
Lymphadenitis (Non-neoplastic)
›Microscopic Features:
- Most do not show a completely effaced lymph node (as opposed to neoplastic processes such as lymphomas)
- The morphology can be variable based on the underlying disease
- Enlarged reactive secondary follicles are commonly seen
- Increased number of Immunoblasts are also commonly noted
›Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
- PB: N/A
- BM: N/A
- LN: N/A
›May Resemble:
›Differential Diagnoses:
Drug-induced
Autoimmune-induced
Infection
Neoplastic (e.g. Follicular lymphoma)
Idiopathic (unknown cause)
Autoimmune-induced
Infection
Neoplastic (e.g. Follicular lymphoma)
Idiopathic (unknown cause)
›Classic Immunophenotype:
- "T"-cells have the "Tiny" CDs: CD2, CD3, CD4, CD5, CD7, CD8
- "B"-cells have the "Bigger" CDs: CD19, CD20, CD22
›Misc:
Non-neoplastic lymphadenitis can be due to infection, drugs, autoimmune, or ideopathic