Lymphadenitis is a disease caused by infection of lymphatic vessels, lymph nodes and lymphoid tissues, mainly manifested as lymph node enlargement and pain. Lymphadenitis can be divided into acute and chronic, in which acute lymphadenitis is usually caused by bacterial infection and chronic lymphadenitis is usually caused by virus infection.

Acute lymphadenitis is usually caused by bacterial infection. The common bacteria are Streptococcus, Staphylococcus and so on. These bacteria invade lymph nodes through lymphatic vessels, causing inflammatory reaction of tissues around lymphatic vessels, resulting in swelling and pain of lymph nodes. Some chronic diseases and immune dysfunction may also increase the risk of lymphadenitis.

Chronic lymphadenitis is usually caused by viral infection. Common viruses are EB virus and HIV virus. These viruses invade lymphatic tissue through lymphatic vessels, causing inflammatory reaction, resulting in swelling and pain of lymphatic tissue. Chronic lymphadenitis usually lasts for a long time, and severe cases can lead to damage and dysfunction of lymphatic tissue.

In addition to bacterial and viral infections, other factors may also cause lymphadenitis, such as oral infection, surgery, tooth extraction and so on. Therefore, it is very important for patients with lymphadenitis to maintain good personal hygiene, pay attention to oral hygiene and treat infection in time.