Mesenteric lymphadenitis: Mostly viral infection, often complicating the course of acute upper respiratory tract infections or secondary to intestinal inflammation. Clinical manifestations: fever, abdominal pain, vomiting, or diarrhea or constipation. Diagnostic criteria: a. Most of the manifestations of fever, abdominal pain, and vomiting are complicated in upper respiratory tract infections or intestinal infections. b, Abdominal pain is common with periumbilical pain, paroxysmal and cramping pain, rebound pain and abdominal muscle tension are rare. c. Abdominal tenderness is not fixed, and may change with the change of body position. d. Ultrasonography shows enlarged mesenteric lymph nodes. Treatment: Antibiotic therapy is the mainstay, with antispasmodic analgesics such as scopolamine. After 3-5 days of treatment, most of the fever subsided, white blood cells decreased significantly, abdominal pain symptoms relieved significantly, after 1 week of anti-infective treatment more cured and discharged. Prevention: a, usually pay attention to the prevention of colds and fever and pay attention to dietary patterns. b. The prognosis of this disease is good, often in 5-7 days of natural remission. c, for the accompanying fever, especially children and young adults, if the precursor symptoms of upper respiratory tract infection should be immediately antiviral, anti-infection and other treatments to prevent the occurrence of acute non-specific mesenteric lymphadenitis.