Toxoplasma Lymphadenitis

Toxoplasma Lymphadenitis: The nodal architecture is generally well-preserved. The three main histologic findings in toxoplasma lymphadenitis are: hyperplastic lymphoid follicles with reactive germinal centers, clusters of epithelioid histiocytes, and sheets of monocytoid B-cells with pale or clear cytoplasm. All three findings may not be well seen in all cases. The lymph node sinuses are distended and lined by hyperplastic endothelial cells. Immunoblasts and plasma cells are present in medullary cords. There are no neutrophils or eosinophils.

The image shows a hyperplastic lymphoid follicle being encroached by clusters of epithelioid histiocytes (pink area on lower left) from a case of toxoplasma lymphadenitis.