Lymphadenitis is a condition in which a nodule the size of a glass ball, with localized redness, swelling and pressure, may appear on the neck, behind the ear, in the armpit or in the groin after a cold or other infection. Acute lymphadenitis that does not heal can become chronic lymphadenitis. Chronic lymphadenitis has pain and tenderness and is usually no more than 2 to 3 cm in diameter and will shrink with anti-inflammatory treatment. Some long-standing chronic lymphadenitis may also have no pain or tenderness. Various injuries and stimuli often cause reactive proliferation of lymphocytes and histiocytes in the lymph nodes, resulting in enlargement of the lymph nodes, called reactive proliferation of the cervical lymph node. There are many causes, including bacteria, viruses, toxins, degenerated tissue components and foreign bodies, all of which can become antigens or allergens that stimulate lymphatic tissue to cause reactions. For example, breast enlargement and thyroid adenoma can cause reactive enlargement of lymph nodes in the neck or axilla. Chronic lymphadenitis is generally difficult to subside, often existing for several years or even for life. The key to making them subside is to treat the primary inflammatory lesion (e.g., enlarged lymph nodes in the neck, treat pharyngitis, tonsillitis, laryngitis, stomatitis, gingivitis, dental caries, etc.). At the same time: 1. do not drink alcohol; 2. do not eat spicy food; 3. use some immune-modifying drugs; 4. herbal treatment. After removal of the primary inflammatory lesions, the lymph nodes tend to shrink and usually do not turn into lymphoma. The treatment of lymph node reactive hyperplasia is also to remove all kinds of damage and irritation. For example, lymph node reactive hyperplasia of the stomach is often associated with H. pylori infection, and if H. pylori is not treated, it may promote gastric lymphoma. Therefore, the prevention of gastric lymphoma requires eradication of H. pylori. Only the persistence of the primary inflammatory lesion or the persistence of various injuries and irritations that lead to persistent reactive proliferation of lymphocytes and histiocytes may turn into lymphoma.