The histopathology of lymphadenopathy in Systemic Lupus Erythematosus (SLE) typically involves several characteristic findings within the lymph nodes. These changes reflect the autoimmune processes underlying SLE.
Lymphadenopathy, or swollen lymph nodes, is a common manifestation observed in individuals with SLE. Pathological examination of these lymph nodes reveals a distinctive set of features.
Key Histopathological Features
Based on histological analysis, the lymph nodes affected by SLE lymphadenopathy may show the following key characteristics:
- Follicular Hyperplasia with Giant Cells: There is an increase in the size and number of lymphoid follicles, which are the areas rich in B cells. Importantly, the presence of giant cells within these hyperplastic follicles can be observed.
- Plasma Cell Infiltration: Plasma cells, which are antibody-producing cells, are found infiltrating the interfollicular zones – the areas between the lymphoid follicles. This reflects the immune activation and antibody production occurring in SLE.
- Necrosis of the Paracortical T-cell Zones: The paracortex, primarily containing T cells, may show areas of cell death (necrosis). This particular feature, especially the necrosis of the T-cell zones, is considered relatively characteristic of SLE lymphadenopathy, helping to distinguish it from other causes of lymph node enlargement.
- LE Bodies: Although rarely seen, "LE bodies" (Lupus Erythematosus bodies) may be identified. These are thought to be nuclear material that has undergone a specific form of denaturation.
- Vascular Changes: The walls of necrotic vessels within the lymph node show deposits of immunoglobulins (such as IgG, IgM) and complement component C3. This deposition highlights the role of immune complexes and complement activation in the tissue damage seen in SLE.
Summary of Histopathological Findings
| Feature | Location/Description | Significance in SLE Lymphadenopathy |
|---|---|---|
| Follicular Hyperplasia | B-cell zones (follicles) | Common reactive change |
| Giant Cells | Within hyperplastic follicles | Associated finding |
| Plasma Cell Infiltration | Interfollicular zones | Reflects humoral immune response |
| Necrosis | Paracortical T-cell zones | Relatively characteristic finding |
| LE Bodies | Within lymph node tissue | Rarely observed |
| Immunoglobulin & C3 Deposition | Walls of necrotic vessels | Evidence of immune complex activity |
These findings collectively paint a picture of an immune-mediated process targeting the lymph nodes, consistent with the systemic nature of SLE. The combination of follicular hyperplasia, paracortical necrosis, plasma cell infiltration, and vascular deposition helps pathologists diagnose SLE lymphadenopathy when examining biopsied lymph nodes.
