Enlarged lymph nodes are enlarged one or more lymph nodes, mostly due to inflammatory infections, reactive hyperplasia, tumors and other reasons. 1. Inflammatory infections: If the body organs or tissues are infected by bacteria, fungi, viruses, tuberculosis bacilli and other infections that cause inflammatory reactions, it is easy to have enlarged lymph nodes. 2. Reactive hyperplasia: acute necrotizing hyperplastic lymphadenopathy, sinus histiocytosis, immune response disease, rheumatic disease, etc. can also cause lymph node enlargement. 3. Tumor: If the body suffers from lymphoma, leukemia, plasma cell tumor, tumor metastasis, etc., it will also cause lymph node enlargement. There may be other reasons for the swelling of lymph nodes, so it is recommended to consult a doctor in time to avoid delaying the condition.