Mesenteric lymphadenitis is generally thought to be due to bloodstream infection by streptococci, but is also thought to be associated with intestinal inflammation and parasitosis. It is most commonly seen at the end of the ileum. The lymph nodes are multiply congested and enlarged. A small amount of inflammatory exudate may be present in the abdominal cavity. Microscopically, the lymphatic sinuses are dilated, and neutrophils enter the lymphatic sinuses by small blood vessels and phagocytose bacteria. Acute mesenteric lymphadenitis is often associated with upper respiratory tract infection. Clinical manifestations are fever, abdominal pain, vomiting, or diarrhea or constipation. Abdominal pain is sometimes like colic in the right lower abdomen, but can also be in other parts of the body, so it is easy to misdiagnose as acute appendicitis, and only proved to be mesenteric lymphadenitis at the time of surgery. The disease is mostly a viral infection, and may resolve spontaneously. However, if the disease recurs or is not treated thoroughly, it may turn into chronic mesenteric lymphadenitis, in which children often have abdominal pain at irregular intervals and in irregular locations, and medication can take a long time. In addition, chronic mesenteric lymphadenitis can also be caused by tuberculosis, accompanied by intestinal tuberculosis or tuberculous peritonitis, with a history of exposure to tuberculosis. Clinical manifestations of chronic tuberculosis toxicity signs, low fever, night sweats, tiredness, poor appetite, abdominal pain, can be in the right lower abdomen or left upper abdomen to find the enlarged lymph nodes, pressure pain obvious. Anti-tuberculosis treatment is generally effective. Surgery may be considered if necessary. If the history is more typical, the abdominal pressure is more extensive, without abdominal muscle tension, non-surgical treatment can be carried out first, with intravenous antibiotics, or with purgatives. Changes in abdominal signs should be closely observed, and other predisposing conditions should be treated promptly if found. It should be noted that it should also be differentiated from lymphoma, which may also manifest as enlargement of mesenteric lymph nodes, and be identified by biopsy.