What are the types of reactive lymph node hyperplasia?

The lymph node is a very important immune organ in the human body. Reactive lymph node hyperplasia is also a common clinical problem, which has a great impact on human health. Therefore, we must take lymph node hyperplasia seriously. There are many types of reactive lymph node hyperplasia, and different types have different treatments. The type of symptoms should also be considered in treatment.

1. Nonspecific reactive lymphoid follicular hyperplasia

The main features of nonspecific reactive lymphofollicular hyperplasia are lymphadenopathy, lymphofollicular hyperplasia, and marked enlargement of germinal centers. The number of lymphoid follicles increases, and they are not only distributed in the lymph node cortex, but also scattered at the cortical-medullary junction and in the medulla. The follicles vary in size and shape, with clear boundaries. The germinal center is significantly enlarged and proliferated, containing a large number of various transformed lymphocytes with large nuclei, with or without cleavage, frequent nuclear division images, and many phagocytes, with phagocytic cell debris in the cytoplasm. The germinal centers are surrounded by small lymphocytes. Infiltration of plasma cells, histiocytes, and a small number of neutrophils and eosinophils can be seen in the lymphoid tissue between the follicles. Reticular cell and endothelial cell proliferation in the lymphatic sinuses. Reactive lymphofollicular hyperplasia is easily confused with follicular lymphoma, in which the lymph node architecture is destroyed, the follicles are similar in size and shape, and the boundaries are not clear. The proliferating cells in the follicles are atypical, but the types are relatively consistent, with fewer mitotic figures, and generally no macrophages engulfing foreign matter are seen. The proliferating lymphocytes are monoclonal; whereas in reactive lymphoid follicular hyperplasia, the proliferating lymphocytes are polyclonal.

2. Angiofollicular lymphadenopathy

Angiofollicular lymphadenopathy is a type of lymphadenopathy of unknown cause, also known as giant lymphadenopathy, Castleman lymphadenopathy, lymphadenoma, angiomatous lymphadenoma, benign giant lymphoma, follicular lymphoreticular cell tumor, lymphoid tissue tumor-like hyperplasia, angiofollicular mediastinal lymphadenopathy, giant intrathoracic lymph nodes, benign thymoma, etc. It is a special type of lymphadenopathy, which is neither a tumor nor a hamartoma. Can occur at any age. Angiofollicular lymphadenopathy most commonly occurs in the mediastinal lymph nodes but may also be seen in the hilar lymph nodes and the cervical, axillary, mesenteric, broad ligament, and retroperitoneal lymph nodes. The lymph nodes are obviously enlarged, with a diameter of 3 to 7 cm, up to 16 cm, and are often round in shape, with an intact capsule and clear boundaries. The cross-section is pale yellowish white with a coarse granular or layered structure, and sometimes there are focal areas that are as hard as cartilage, without bleeding or necrosis.

3. Angioimmunoblastic lymphadenopathy

Angioimmunoblastic lymphadenopathy, also known as immunoblastic lymphadenopathy, often occurs in middle-aged and elderly people. The main manifestations are fever, weight loss, generalized lymphadenopathy, hepatomegaly and splenomegaly, maculopapular rash on the skin, itching, and often polyclonal hypergammaglobulinemia and hemolytic anemia. The main lesion of immunoblastic lymphadenopathy is enlarged lymph nodes throughout the body. The lymph nodes are generally about 2 to 3 cm in diameter, grayish white, soft, movable, and sometimes tender. Microscopically, the lymph node structure disappears, and the lymph follicles and lymph sinuses are not obvious. The lymph nodes are infiltrated with a large number of immunoblasts and transformed lymphocytes. Sometimes there are also numerous plasma cells, eosinophils, macrophages, and epithelioid cells. The postcapillary venules proliferate significantly and are branched. Vascular endothelial cells swell and proliferate. Amorphous eosin-like material deposits can be seen in the lymph node interstitium. In addition to lymph nodes, similar lesions can also be seen in the liver, spleen, bone marrow, and lungs.