Swollen mesenteric lymph nodes are usually found in children or adolescents, mostly due to inflammation, commonly caused by bacterial or viral infections, resulting in swollen mesenteric lymph nodes, such as frequent colds or lack of hygiene in children, resulting in the entry of bacteria or viruses into the body and intermittent abdominal pain, diarrhea, abdominal distention, and blood in the stool. For treatment, anti-infection treatment is mainly taken, or antibiotics are given for anti-inflammatory treatment. If the symptoms of enlarged mesenteric nodes appear in the elderly, they are also mostly caused by inflammation, and it is necessary to consider whether they have tumor factors, and tumors of the urinary system and digestive tract can cause enlarged mesenteric lymph nodes. Patients with tumors may experience anemia, emaciation, abnormal bowel movements, such as unformed stools and black stools, etc. Clinically, patients in the early stage of the disease are recommended to be treated with timely surgical radical resection.