Although mesenteric lymphadenitis is most common in children, it can also occur in the elderly. The disease is associated with infection by a variety of pathogenic microorganisms, such as viruses, bacteria, and parasites. Mesenteric lymphadenitis is an infectious disease caused by viral infections, such as Coxsackie virus; bacterial infections, such as streptococcus, salmonella, and Escherichia coli; and parasitic infections, such as amoebas, roundworms, etc. It most often occurs after upper respiratory tract infections and acute gastroenteritis. The disease often occurs in children and adolescents between the ages of 3 and 15, but it may also occur in the elderly. Low immunity, poor personal hygiene and malnutrition are risk factors for the disease. In the elderly, the presence of abdominal pain and other abdominal discomforts due to infectious diseases should be noted for the possibility of enlarged mesenteric lymph nodes. At this time, we should consult the doctor in time, complete the examination, and follow the doctor’s instructions to be treated accordingly after the diagnosis is clear.