by Jason Wasserman MD PhD FRCPC
June 17, 2022
‘Reactive lymphoid hyperplasia’ is a term used to describe an increased number of specialized immune cells called ‘lymphocytes’. It is a non-cancerous change. Reactive lymphoid hyperplasia is commonly seen in small immune organs called lymph nodes, which may appear enlarged. This change may also be seen in other organs where a large number of lymphocytes are normally found. This includes the stomach, small intestine, skin, and oropharynx (especially the tonsils).
Reactive lymphoid hyperplasia can be caused by anything that stimulates or activates lymphocytes. The most common cause is a viral or bacterial infection. Lymphocytes can also be stimulated by injury to the tissue, allergies, and drugs/medications. Rarely, reactive lymphoid hyperplasia is caused by an immune system disorder or autoimmune disease.
The diagnosis of reactive lymphoid hyperplasia is usually made after small pieces of tissue are removed in a procedure called a biopsy. When a lymph node is involved, the entire lymph node may be removed in a procedure called an excision. The tissue is then sent to a pathologist for examination under the microscope.
This picture shows reactive lymphoid hyperplasia in a lymph node.