Worms in the colon can be a left abdominal pain, but may also be manifested by abdominal pain in different parts of the body, abdominal distension, gastrointestinal bleeding, lethargy, anemia, and so on. Different intestinal parasites may have different clinical manifestations. 1. Ascaris lumbricoides:When there are roundworms in the intestinal tract, patients may be asymptomatic, or they may show symptoms such as periumbilical pain, loss of appetite, nausea, vomiting, etc., and in severe cases, they may have symptoms of mental restlessness and irritability. 2. Amebic dysentery: generally asymptomatic, can be a carrier of the pathogen, the general symptoms can also be manifested as mucous pus and blood stools, abdominal cramps, but also lethargy, anemia, severe cases can be accompanied by intestinal hemorrhage, intestinal perforation. 3. Hookworm: patients with intestinal infection of hookworm will cause intestinal mucosal damage, itching, papules, abdominal pain, anemia, lethargy, fatigue and other symptoms. Patients with the above symptoms should go to the hospital in time, clear causes under the guidance of the doctor.